Cultural Evolution Shifts the Source of Happiness from Religion to Subjective Freedom. Michael Minkov, Christian Welzel & Michael Schachner. Journal of Happiness Studies, Jan 8 2020. https://link.springer.com/article/10.1007/s10902-019-00203-w
Abstract: Numerous studies have reported a positive individual-level association between happiness and two psychologically distinct states of mind: religious faith and subjective freedom (a feeling of life control). Although the strength of these relationships varies across countries, no general pattern driving this variation has been shown so far. After surveying 40,534 randomly selected respondents from 43 nations, we find that in countries where happiness is more closely related to religious faith, it is less strongly associated with subjective freedom, and vice versa. We have also identified the driving force behind this inverse relationship. Rising individualism and emancipative values, as an outcome of modernization, diminish the importance of religious faith for people’s happiness, while increasing the importance of subjective freedom. We conclude that the dominant emancipatory direction of cultural evolution favors freedom over religion.
Wednesday, January 8, 2020
An Initial Test of the Cosmetics Dehumanization Hypothesis: Heavy Makeup Diminishes Attributions of Humanness-Related Traits to Women
An Initial Test of the Cosmetics Dehumanization Hypothesis: Heavy
Makeup Diminishes Attributions of Humanness-Related Traits to Women.
Philippe Bernard, Joanne Content, Lara Servais, Robin Wollast &
Sarah Gervais. Sex Roles, January 8 2020.
https://link.springer.com/article/10.1007/s11199-019-01115-y
Abstract: Objectification theory suggests that sexualization has significant dehumanizing consequences for how perceivers see women. To date, research has mostly documented how sexualized bodies in the mass media are objectified and dehumanized. The purpose of the present work was to test the novel cosmetics dehumanization hypothesis (CDH), that is, that subtler manifestations of sexualization, such as heavy makeup, might influence the way people attribute humanness-related traits to women. Across four experiments, 1000 participants (mostly from the United Kingdom and United States) were asked to evaluate women’s faces with or without heavy makeup. Consistent with the CDH, results showed that faces with makeup were rated as less human while using complementary indicators of dehumanization: They were perceived as possessing less humanness, less agency, less experience (Experiment 1), less competence, less warmth, and less morality (Experiments 2–4) than faces without makeup. This pattern of results was observed for faces of both models (Experiments 1–2) and ordinary women (Experiments 3–4). In Experiment 4, we manipulated the part of the face that wore makeup (eye makeup vs. lipstick) and found that faces with eye makeup were attributed the least amount of warmth and competence. A meta-analysis based on Experiments 2–4 confirmed the robustness of the findings, which were not moderated by either participant gender or sexual orientation. Whereas prior studies suggested that a focus on faces may serve as an antidote for objectification and related dehumanization, the present set of experiments indicates that this strategy might not always be effective.
Abstract: Objectification theory suggests that sexualization has significant dehumanizing consequences for how perceivers see women. To date, research has mostly documented how sexualized bodies in the mass media are objectified and dehumanized. The purpose of the present work was to test the novel cosmetics dehumanization hypothesis (CDH), that is, that subtler manifestations of sexualization, such as heavy makeup, might influence the way people attribute humanness-related traits to women. Across four experiments, 1000 participants (mostly from the United Kingdom and United States) were asked to evaluate women’s faces with or without heavy makeup. Consistent with the CDH, results showed that faces with makeup were rated as less human while using complementary indicators of dehumanization: They were perceived as possessing less humanness, less agency, less experience (Experiment 1), less competence, less warmth, and less morality (Experiments 2–4) than faces without makeup. This pattern of results was observed for faces of both models (Experiments 1–2) and ordinary women (Experiments 3–4). In Experiment 4, we manipulated the part of the face that wore makeup (eye makeup vs. lipstick) and found that faces with eye makeup were attributed the least amount of warmth and competence. A meta-analysis based on Experiments 2–4 confirmed the robustness of the findings, which were not moderated by either participant gender or sexual orientation. Whereas prior studies suggested that a focus on faces may serve as an antidote for objectification and related dehumanization, the present set of experiments indicates that this strategy might not always be effective.
The green mate appeal: Men's pro‐environmental consumption is an honest signal of commitment to their partner
The green mate appeal: Men's pro‐environmental consumption is an honest signal of commitment to their partner. Sylvie Borau, Leila Elgaaied‐Gambier, Camilla Barbarossa. Psychology & Marketing, January 7 2020. https://doi.org/10.1002/mar.21321
Abstract: Green consumption is associated with femininity. This green‐feminine stereotype has been accused of deterring men from buying green products to protect their gender identity. Here, we investigate whether men can benefit from this green‐feminine stereotype, beyond the status effect of green conspicuous consumption. We propose that green consumption can act as a signal of altruism and high commitment both as a partner and as a father. Based on evidence showing that these traits are sought in a long‐term partner, we predict that men can increase their value as long‐term mates by engaging in green consumption. We also investigate whether men involved in a long‐term mating relationship are indeed eco‐friendlier, testing the novel hypothesis that green consumption is an honest signal of commitment. Finally, we specify the type of commitment that is associated with men's green consumption. Across six studies, our findings suggest that green consumption is an honest signal of men's long‐term mating value and that it is a more reliable sign of partner commitment than of father commitment. We discuss how companies and governments can use these findings to increase green consumption among men.
Abstract: Green consumption is associated with femininity. This green‐feminine stereotype has been accused of deterring men from buying green products to protect their gender identity. Here, we investigate whether men can benefit from this green‐feminine stereotype, beyond the status effect of green conspicuous consumption. We propose that green consumption can act as a signal of altruism and high commitment both as a partner and as a father. Based on evidence showing that these traits are sought in a long‐term partner, we predict that men can increase their value as long‐term mates by engaging in green consumption. We also investigate whether men involved in a long‐term mating relationship are indeed eco‐friendlier, testing the novel hypothesis that green consumption is an honest signal of commitment. Finally, we specify the type of commitment that is associated with men's green consumption. Across six studies, our findings suggest that green consumption is an honest signal of men's long‐term mating value and that it is a more reliable sign of partner commitment than of father commitment. We discuss how companies and governments can use these findings to increase green consumption among men.
Although appearing nervous and awkward during an initial encounter with an attractive other may seem counterproductive for future mating success, the reaction may have potential adaptive value
Perceived Nervous Reactions during Initial Attraction and Their Potential Adaptive Value. Susan M. Hughes, Marissa A. Harrison & Kathleen M. de Haan. Adaptive Human Behavior and Physiology, Jan 7 2020. https://link.springer.com/article/10.1007/s40750-019-00127-y
Abstract
Objective: We sought to examine perceived nervous reactions when first interacting with a particularly attractive person/potential romantic partner. From a theoretical standpoint, we cogitate on the possible adaptive nature of these reactions that appear seemingly counterproductive for future mating success.
Methods: We documented 280 participants’ retrospective self-reports of experiencing a variety of physiological, vocal, and behavioral reactions during an initial encounter with a person they found highly attractive. We also asked participants to rate the reactions of others that they used to determine if another person was attracted to them.
Results: Participants reported most frequently experiencing increased attentiveness, smiling, staring, heart rate, giggling/laughter, blushing, and difficulty concentrating during this first encounter. Both sexes reported speaking faster and being less able to express themselves clearly, and women reported using a higher pitch and having a more unsteady tone of voice during an initial encounter of attraction. Further, participants reported observing similar nervous reactions by others whom they perceived were attracted to them. These findings were examined while considering individual differences in sociosexual orientation (i.e., propensity toward uncommitted sex), self-perceived mate value, empathy, and gender.
Conclusions: Participants reported that they did, indeed, experience a cluster of anxiety-related physiological and behavioral reactions during an initial encounter with someone they found highly attractive. Although appearing nervous and awkward during an initial encounter with an attractive other may seem counterproductive for future mating success, we discuss potential adaptive functions for displaying these responses.
Reasons why Nervous Responses during Initial Attraction May be Adaptive
Whereas it was our aim to document the cluster of nervous reactions upon initial
encounter, it is of interest to explore the adaptive function of these physiological
responses reported in this study. At first glance, it would not appear adaptive for
someone to display nervous reactions during an initial encounter with an attractive,
potential mate. These reactions may make an individual seem awkward, clumsy,
ignorant, and uncomfortable and may deter one from considering that person as a
potential mate. Even though these reactions seem counterproductive for future mating
success, our data show that people report they are prevalent. Because the reproductive
consequences of a behavior affect the incidence of that behavior in subsequent
generations, this cluster of nervous signs may serve some adaptive function. Below we
present six possible adaptive reasons why nervous reactions during an initial encounter
with a potential mate are common.
Strong, Honest Sign of Mate Interest
These nervous reactions may serve an adaptive
function of being a salient signal of reproductive interest. In particular, attraction/
romantic interest can be easily distinguished through vocal tones (Hughes et al.,
2010). It may be difficult to mask anxious reactions during this encounter. Particularly
for men, because nervousness can cause problems with cognitive performance
(Karremans et al., 2009; Sarason, 1984), nervousness may make it more difficult for
a man to disguise his true feelings and display phony traits during an initial encounter.
Therefore, these reactions may serve as an honest signal of interest when in the
presence of a potential mate. It is also adaptive to attend to cues of romantic interest
to either avoid or engage in expending energy on individuals who may or may not be
interested or available (Bendixen et al., 2019; Floyd, Judd, & Hesse, 2008).
Both male and female participants indeed reported experiencing several physiological and behavioral reactions when first talking in person to someone whom they found
highly attractive and deem a potential romantic partner. Although the documented
responses occur typically under conditions of “fight or flight” (Marks & Neese, 1994),
we argue that this cluster of signals can be thought of as a psychobiological signature of
honest interest, and these reactions in the presence of a potential mate may serve an
adaptive function of signaling reproductive interest, enhancing the chances of obtaining
a desired mate. Given that our sample was a good representation of peak reproductive
years (a mean of 29.1 with a standard deviation of 12.7 years; Dunson, Baird, &
Colombo, 2004), our participants likely had an increased opportunity to experience
these reactions during initial attraction compared to younger, traditional, college-age
samples typically recruited in other research.
Trigger Reciprocal Feelings
Signs of romantic interest often trigger reciprocal feelings
(Kenny & La Voie, 1982; Montoya & Insko, 2008), and as reported by our participants,
people use these nervous reactions to assess whether another person is attracted to
them. Research shows that when one is made aware that a person is attracted to them,
they become more attracted to that person; but people need to be aware of other’s
feelings toward them for strong reciprocal liking to occur (Luo & Zhang, 2009).
Noticing reciprocation of interest would be particularly advantageous so as to decrease
the chances of missing a mating opportunity and avoid the risk of being rejected.
More Effective Communication Research has shown that when put in a stressful
situation, some aspects speech quality decreases such that speech fluency (as measured
by pause time) is significantly reduced and the frequency of flustered speech increases
(Buchanan, Laures-Gore, & Duff, 2014; Kasl & Mahl, 1965). However, several other
aspects of speech quality are actually enhanced during stressful situations, perhaps
unbeknownst to the speaker. For instance, under instances of stress, communication
rate (words per minute) increases, productive language (ratio of productive to nonproductive speech) increases (which is particularly pronounced during the early part of a
speech task), the use of non-fluencies (such as hmm, uh, um, etc.) is less likely, and
word-finding difficulties do not seem to impair speech (Buchanan et al., 2014). Thus, it
can be argued that when a person becomes anxious when first speaking to someone to
whom they are attracted, their semantic communication is essentially more effective.
We also found that women reported raising the pitch of their voice, which may have
made them sound more attractive. Thus, these speech patterns that occur under the
stress of an initial interaction may actually enhance the chances of impressing and
attaining the desired mate.
Indication of Desirable Traits Associated with those Who Exhibit Nervous Behavior
Anxious individuals have been shown to be more adept at conveying positive
qualities and appeared more willing to engage; they appeared nicer, more interesting,
and more conversational, all of which could increase their desirability (Brumbaugh &
Fraley, 2010). A person who exhibits nervous reactions during initial attraction could
serve as an indication to a potential mate (particularly women) that the suitor possesses
other personality traits that would be favorable in long-term relationships and for future
parenting such as being sensitive, caring, and responsive.
People generally like those who are more facially expressive, and it is seen
as more attractive (Sabatelli & Rubin, 1986). As such, people show greater
facial movement during high versus low anxiety situations (Harrigan &
O’Connell, 1996), and nonverbal expressiveness positively impacts interpersonal
perceptions (Sabatelli & Rubin, 1986). Having a more expressive nature, including displaying nervousness, could also demonstrate other positive characteristics that people find attractive (Sabatelli & Rubin, 1986). In fact, nonverbal
expressiveness could even compensate for a lack of physical attractiveness and
may enhance initial interpersonal impressions so as to allow the person to
appear more attractive (Sabetelli & Rubin, 1986). Along these lines, previous
research has shown that men were more likely to be accepted as a potential
romantic partner during a speed-dating event when they arrived with elevated
levels of the stress hormone, cortisol (van der Meij et al., 2019) suggesting that
being nervous may have its advantages.
Sweating Allows for the Release of Pheromones
Nervously sweating during an initial encounter with an attractive, potential mate may increase the release of pheromones
which can serve as a chemical signal of attraction to the recipient (Saxton et al., 2008).
When individuals become anxious, they tend to show increased palmar sweat (Kasl &
Mahl, 1965) and body perspiration (Galassi et al., 1981) and there is evidence to
suggest that human pheromones are released through these axillary sweat glands (Beier,
Ginez, & Schaller, 2005). Pheromones signal sexual readiness in other species and
likely do so in humans (Thornhill, Chapman, & Gangestad, 2013) and can affect
perceptions of attraction in humans (Rantala, Eriksson, Vainikka, & Kortet, 2006;
Thornhill & Gangestad, 1999; Wyart et al., 2007). For instance, women who were
exposed to androstadienone, a purported male pheromone released by axillary sweat
glands, gave men at a speed dating event higher attractiveness ratings than did women
with no exposure (Saxton, Lyndon, Little, & Roberts, 2008). Exposure to
androstadienone appears to increase sexual response, increase focus, and improve
mood in women (Jacob, Hayreh, & McClintock, 2001; Hummer & McClintock,
2009; Jacob, Garcia, Hayreh, & McClintock, 2002; Verhaeghe, Gheysen, & Enzlin,
2013). Further, release of pheromones has been shown to be valuable for making mate
assessments and can facilitate quick judgments (Hummer & McClintock, 2009;
Thornhill & Gangestad, 1999).
Pheromones may have other direct influences on the recipient. Pheromone exposure
affects skin temperature and conductance (Jacob et al., 2001) and cortisol levels (Wyart
et al., 2007). Thus, it is possible that the recipient could interpret one’s own physiological arousal caused by the pheromone exposure to be the result of their own attraction to
the sender. In addition, there is some evidence from the animal kingdom that pheromones serve to appease conspecifics (Pageat & Gaultier, 2003). Indeed, empathetic
responses to signals in sweat have been documented in humans. Prehn-Kristensen et al.
(2009) found that exposure to sweat from individuals in anxiety-provoking situations
activated areas of the brain related to emotional processing and empathy regulation.
Future studies may explore how pheromones released during this nervous interaction
with a potential mate could influence human opposite-sex conspecifics.
Aid in the Assessment of Matching Mate Value
Mutual nervousness could reveal
matching mate value whereas if only one person is nervous and the other is not, then
this could be a sign of a mismatch in mate value. In other words, whether one, both, or
neither persons of the dyad experiences nervousness when meeting for the first time
could help to differentiate between those who have a matching mate value from those
who are discordant. Individuals generally tend to desire mates with some level of
similarity to themselves and who are of matching social desirability (Berscheid,
Walster, & Walster, 1971; Buston & Emlen, 2003; Figueredo, Sefcek, & Jones,
2006), which often reflects a desire for someone of matching mate value. Back et al.
(2011) argued that knowing one’s own mate value is essential to reproductive to
success. Further, one could view any arousal felt when reciprocating that attention
from a potential mate as a signal of matching mate value.
Abstract
Objective: We sought to examine perceived nervous reactions when first interacting with a particularly attractive person/potential romantic partner. From a theoretical standpoint, we cogitate on the possible adaptive nature of these reactions that appear seemingly counterproductive for future mating success.
Methods: We documented 280 participants’ retrospective self-reports of experiencing a variety of physiological, vocal, and behavioral reactions during an initial encounter with a person they found highly attractive. We also asked participants to rate the reactions of others that they used to determine if another person was attracted to them.
Results: Participants reported most frequently experiencing increased attentiveness, smiling, staring, heart rate, giggling/laughter, blushing, and difficulty concentrating during this first encounter. Both sexes reported speaking faster and being less able to express themselves clearly, and women reported using a higher pitch and having a more unsteady tone of voice during an initial encounter of attraction. Further, participants reported observing similar nervous reactions by others whom they perceived were attracted to them. These findings were examined while considering individual differences in sociosexual orientation (i.e., propensity toward uncommitted sex), self-perceived mate value, empathy, and gender.
Conclusions: Participants reported that they did, indeed, experience a cluster of anxiety-related physiological and behavioral reactions during an initial encounter with someone they found highly attractive. Although appearing nervous and awkward during an initial encounter with an attractive other may seem counterproductive for future mating success, we discuss potential adaptive functions for displaying these responses.
Reasons why Nervous Responses during Initial Attraction May be Adaptive
Whereas it was our aim to document the cluster of nervous reactions upon initial
encounter, it is of interest to explore the adaptive function of these physiological
responses reported in this study. At first glance, it would not appear adaptive for
someone to display nervous reactions during an initial encounter with an attractive,
potential mate. These reactions may make an individual seem awkward, clumsy,
ignorant, and uncomfortable and may deter one from considering that person as a
potential mate. Even though these reactions seem counterproductive for future mating
success, our data show that people report they are prevalent. Because the reproductive
consequences of a behavior affect the incidence of that behavior in subsequent
generations, this cluster of nervous signs may serve some adaptive function. Below we
present six possible adaptive reasons why nervous reactions during an initial encounter
with a potential mate are common.
Strong, Honest Sign of Mate Interest
These nervous reactions may serve an adaptive
function of being a salient signal of reproductive interest. In particular, attraction/
romantic interest can be easily distinguished through vocal tones (Hughes et al.,
2010). It may be difficult to mask anxious reactions during this encounter. Particularly
for men, because nervousness can cause problems with cognitive performance
(Karremans et al., 2009; Sarason, 1984), nervousness may make it more difficult for
a man to disguise his true feelings and display phony traits during an initial encounter.
Therefore, these reactions may serve as an honest signal of interest when in the
presence of a potential mate. It is also adaptive to attend to cues of romantic interest
to either avoid or engage in expending energy on individuals who may or may not be
interested or available (Bendixen et al., 2019; Floyd, Judd, & Hesse, 2008).
Both male and female participants indeed reported experiencing several physiological and behavioral reactions when first talking in person to someone whom they found
highly attractive and deem a potential romantic partner. Although the documented
responses occur typically under conditions of “fight or flight” (Marks & Neese, 1994),
we argue that this cluster of signals can be thought of as a psychobiological signature of
honest interest, and these reactions in the presence of a potential mate may serve an
adaptive function of signaling reproductive interest, enhancing the chances of obtaining
a desired mate. Given that our sample was a good representation of peak reproductive
years (a mean of 29.1 with a standard deviation of 12.7 years; Dunson, Baird, &
Colombo, 2004), our participants likely had an increased opportunity to experience
these reactions during initial attraction compared to younger, traditional, college-age
samples typically recruited in other research.
Trigger Reciprocal Feelings
Signs of romantic interest often trigger reciprocal feelings
(Kenny & La Voie, 1982; Montoya & Insko, 2008), and as reported by our participants,
people use these nervous reactions to assess whether another person is attracted to
them. Research shows that when one is made aware that a person is attracted to them,
they become more attracted to that person; but people need to be aware of other’s
feelings toward them for strong reciprocal liking to occur (Luo & Zhang, 2009).
Noticing reciprocation of interest would be particularly advantageous so as to decrease
the chances of missing a mating opportunity and avoid the risk of being rejected.
More Effective Communication Research has shown that when put in a stressful
situation, some aspects speech quality decreases such that speech fluency (as measured
by pause time) is significantly reduced and the frequency of flustered speech increases
(Buchanan, Laures-Gore, & Duff, 2014; Kasl & Mahl, 1965). However, several other
aspects of speech quality are actually enhanced during stressful situations, perhaps
unbeknownst to the speaker. For instance, under instances of stress, communication
rate (words per minute) increases, productive language (ratio of productive to nonproductive speech) increases (which is particularly pronounced during the early part of a
speech task), the use of non-fluencies (such as hmm, uh, um, etc.) is less likely, and
word-finding difficulties do not seem to impair speech (Buchanan et al., 2014). Thus, it
can be argued that when a person becomes anxious when first speaking to someone to
whom they are attracted, their semantic communication is essentially more effective.
We also found that women reported raising the pitch of their voice, which may have
made them sound more attractive. Thus, these speech patterns that occur under the
stress of an initial interaction may actually enhance the chances of impressing and
attaining the desired mate.
Indication of Desirable Traits Associated with those Who Exhibit Nervous Behavior
Anxious individuals have been shown to be more adept at conveying positive
qualities and appeared more willing to engage; they appeared nicer, more interesting,
and more conversational, all of which could increase their desirability (Brumbaugh &
Fraley, 2010). A person who exhibits nervous reactions during initial attraction could
serve as an indication to a potential mate (particularly women) that the suitor possesses
other personality traits that would be favorable in long-term relationships and for future
parenting such as being sensitive, caring, and responsive.
People generally like those who are more facially expressive, and it is seen
as more attractive (Sabatelli & Rubin, 1986). As such, people show greater
facial movement during high versus low anxiety situations (Harrigan &
O’Connell, 1996), and nonverbal expressiveness positively impacts interpersonal
perceptions (Sabatelli & Rubin, 1986). Having a more expressive nature, including displaying nervousness, could also demonstrate other positive characteristics that people find attractive (Sabatelli & Rubin, 1986). In fact, nonverbal
expressiveness could even compensate for a lack of physical attractiveness and
may enhance initial interpersonal impressions so as to allow the person to
appear more attractive (Sabetelli & Rubin, 1986). Along these lines, previous
research has shown that men were more likely to be accepted as a potential
romantic partner during a speed-dating event when they arrived with elevated
levels of the stress hormone, cortisol (van der Meij et al., 2019) suggesting that
being nervous may have its advantages.
Sweating Allows for the Release of Pheromones
Nervously sweating during an initial encounter with an attractive, potential mate may increase the release of pheromones
which can serve as a chemical signal of attraction to the recipient (Saxton et al., 2008).
When individuals become anxious, they tend to show increased palmar sweat (Kasl &
Mahl, 1965) and body perspiration (Galassi et al., 1981) and there is evidence to
suggest that human pheromones are released through these axillary sweat glands (Beier,
Ginez, & Schaller, 2005). Pheromones signal sexual readiness in other species and
likely do so in humans (Thornhill, Chapman, & Gangestad, 2013) and can affect
perceptions of attraction in humans (Rantala, Eriksson, Vainikka, & Kortet, 2006;
Thornhill & Gangestad, 1999; Wyart et al., 2007). For instance, women who were
exposed to androstadienone, a purported male pheromone released by axillary sweat
glands, gave men at a speed dating event higher attractiveness ratings than did women
with no exposure (Saxton, Lyndon, Little, & Roberts, 2008). Exposure to
androstadienone appears to increase sexual response, increase focus, and improve
mood in women (Jacob, Hayreh, & McClintock, 2001; Hummer & McClintock,
2009; Jacob, Garcia, Hayreh, & McClintock, 2002; Verhaeghe, Gheysen, & Enzlin,
2013). Further, release of pheromones has been shown to be valuable for making mate
assessments and can facilitate quick judgments (Hummer & McClintock, 2009;
Thornhill & Gangestad, 1999).
Pheromones may have other direct influences on the recipient. Pheromone exposure
affects skin temperature and conductance (Jacob et al., 2001) and cortisol levels (Wyart
et al., 2007). Thus, it is possible that the recipient could interpret one’s own physiological arousal caused by the pheromone exposure to be the result of their own attraction to
the sender. In addition, there is some evidence from the animal kingdom that pheromones serve to appease conspecifics (Pageat & Gaultier, 2003). Indeed, empathetic
responses to signals in sweat have been documented in humans. Prehn-Kristensen et al.
(2009) found that exposure to sweat from individuals in anxiety-provoking situations
activated areas of the brain related to emotional processing and empathy regulation.
Future studies may explore how pheromones released during this nervous interaction
with a potential mate could influence human opposite-sex conspecifics.
Aid in the Assessment of Matching Mate Value
Mutual nervousness could reveal
matching mate value whereas if only one person is nervous and the other is not, then
this could be a sign of a mismatch in mate value. In other words, whether one, both, or
neither persons of the dyad experiences nervousness when meeting for the first time
could help to differentiate between those who have a matching mate value from those
who are discordant. Individuals generally tend to desire mates with some level of
similarity to themselves and who are of matching social desirability (Berscheid,
Walster, & Walster, 1971; Buston & Emlen, 2003; Figueredo, Sefcek, & Jones,
2006), which often reflects a desire for someone of matching mate value. Back et al.
(2011) argued that knowing one’s own mate value is essential to reproductive to
success. Further, one could view any arousal felt when reciprocating that attention
from a potential mate as a signal of matching mate value.
Tuesday, January 7, 2020
Intellectual, narcissistic, or Machiavellian? How Twitter users differ from Facebook-only users
Marshall, T. C., Ferenczi, N., Lefringhausen, K., Hill, S., & Deng, J. (2020). Intellectual, narcissistic, or Machiavellian? How Twitter users differ from Facebook-only users, why they use Twitter, and what they tweet about. Psychology of Popular Media, 9(1), 14-30. Jan 2020. http://dx.doi.org/10.1037/ppm0000209
Abstract: Twitter is one of the world’s most popular social networking sites, yet gaps remain in our knowledge about the psychology of its users. The current studies sought to fill these gaps by examining whether the Big Five and Dark Triad personality traits predicted differences between Twitter users and Facebook-only users, motives for using Twitter, the frequency of tweeting about 4 topics—intellectual pursuits, personal achievements, diet/exercise, and social activities—and how much they liked to read tweets about these topics. Study 1 found that Twitter users (N = 346) were higher in openness (i.e., intellect and creativity) than Facebook-only users (N = 268). In Study 2, a preregistered replication, Twitter users (N = 255) were not only higher in openness than Facebook-only users (N = 248), but they were also more Machiavellian. In both studies, Twitter users who were higher in openness were more strongly motivated to use Twitter for career promotion, and in turn, they tweeted more frequently and most liked to read tweets about intellectual pursuits. Narcissists were more strongly motivated to use Twitter for career promotion, social connection, and attention-seeking, and in turn, they tweeted more frequently and most liked to read tweets about personal achievements and diet/exercise. On average, participants most liked to read tweets about intellectual pursuits and least liked tweets about diet/exercise. We discuss the implications of these findings for tailoring one’s tweets to retain followers and for drawing the boundary conditions when extrapolating from Twitter-based “big data” to larger populations.
Public Policy Relevance Statement: Twitter users significantly differed in their personality traits from Facebook-only users, suggesting that social scientists take caution when generalizing from Twitter-based “big data” to larger populations. Our finding that Twitter particularly attracts open-minded individuals who wish to advance their careers through tweeting about intellectual topics has relevance for not only individuals wishing to maximize their use of social media but also Twitter’s marketing and retention strategies.
KEYWORDS: Twitter, Facebook, social media, Big Five personality traits, Dark Triad
Abstract: Twitter is one of the world’s most popular social networking sites, yet gaps remain in our knowledge about the psychology of its users. The current studies sought to fill these gaps by examining whether the Big Five and Dark Triad personality traits predicted differences between Twitter users and Facebook-only users, motives for using Twitter, the frequency of tweeting about 4 topics—intellectual pursuits, personal achievements, diet/exercise, and social activities—and how much they liked to read tweets about these topics. Study 1 found that Twitter users (N = 346) were higher in openness (i.e., intellect and creativity) than Facebook-only users (N = 268). In Study 2, a preregistered replication, Twitter users (N = 255) were not only higher in openness than Facebook-only users (N = 248), but they were also more Machiavellian. In both studies, Twitter users who were higher in openness were more strongly motivated to use Twitter for career promotion, and in turn, they tweeted more frequently and most liked to read tweets about intellectual pursuits. Narcissists were more strongly motivated to use Twitter for career promotion, social connection, and attention-seeking, and in turn, they tweeted more frequently and most liked to read tweets about personal achievements and diet/exercise. On average, participants most liked to read tweets about intellectual pursuits and least liked tweets about diet/exercise. We discuss the implications of these findings for tailoring one’s tweets to retain followers and for drawing the boundary conditions when extrapolating from Twitter-based “big data” to larger populations.
Public Policy Relevance Statement: Twitter users significantly differed in their personality traits from Facebook-only users, suggesting that social scientists take caution when generalizing from Twitter-based “big data” to larger populations. Our finding that Twitter particularly attracts open-minded individuals who wish to advance their careers through tweeting about intellectual topics has relevance for not only individuals wishing to maximize their use of social media but also Twitter’s marketing and retention strategies.
KEYWORDS: Twitter, Facebook, social media, Big Five personality traits, Dark Triad
General Discussion
This research is the first to examine the Big Five and Dark Triad traits as simultaneous predictors of the likelihood of using Twitter versus Facebook-only, motives for using Twitter, frequency of tweeting about and likability of various topics, and the number of likes/retweets typically received. Our results confirmed that there does indeed appear to be something unique about people who use Twitter rather than just Facebook: They are higher in openness and Machiavellianism. We review these findings in more detail next, and discuss the implications for enhancing users’ experience of Twitter and the extent to which social scientists may generalize from Twitter data to larger populations.
Openness
We found, in both studies, that openness was positively associated with the likelihood of being a Twitter user, with using Twitter for career promotion and, in turn, with tweeting more frequently about intellectual topics. Highly open individuals, who are often entrepreneurial (Leutner, Ahmetoglu, Akhtar, & Chamorro-Premuzic, 2014) and pursuing scientific or artistic careers (Feist, 1998), may be particularly attracted to Twitter because it allows them to share their creative output, keep up-to-date on the latest work in their field, and network with colleagues. Indeed, almost half of scientists use social media to exchange research findings (Rainie, Funk, & Anderson, 2015). Surprisingly, we did not find that highly open individuals were more strongly motivated to use Twitter for information-seeking, as they tend to be in their use of Facebook (Marshall et al., 2015). Further research, with larger and more diverse samples, will need to confirm that highly open individuals are indeed attracted to Twitter, specifically for the career opportunities it affords rather than for its more general use as a tool for seeking and sharing information.
Extraversion
Extraverts tweeted more often about their social activities and everyday life in Study 1, but this finding was not replicated in Study 2. Moreover, extraverts were not more strongly motivated to use Twitter for social connection in either study, suggesting that, despite some of the social affordances Twitter provides (Chen, 2011), extraverts may still prefer to use other social media sites like Facebook for socializing (Hughes et al., 2012).
Narcissism
In both studies, narcissism was more strongly associated with the various motives for using Twitter and with tweeting about more topics than any other personality trait. Nonetheless, narcissists were not any more likely to use Twitter than Facebook-only, suggesting that Twitter’s affordances—particularly the potential to gain admiration from weak-tie contacts—may not be sufficiently alluring to narcissists. Still, the present studies confirmed several hypotheses. First, narcissists’ greater frequency of tweeting about personal achievements was motivated by their use of Twitter for career promotion (Studies 1 and 2) and attention-seeking (Study 2). Unexpectedly, it was also motivated by their use of Twitter for social connection (Studies 1 and 2), suggesting that narcissists may brag about their accomplishments not only for self-promotion but also to communicate with and feel closer to others. Perhaps they view these tweets simply as a way of sharing good news—a capitalization attempt that may enhance friendship quality (Demir, Doğan, & Procsal, 2013). Narcissists’ greater use of Twitter for social connection also motivated their more frequent tweets about their social activities and everyday life (Study 1), consistent with findings that narcissists’ tweets are more likely to refer to friends (Sumner et al., 2012) and everyday life (Preotiuc-Pietro et al., 2017).
Nevertheless, narcissists’ tweets about social activities were also motivated by their use of Twitter for attention-seeking, suggesting that their motives for posting such tweets may not be entirely prosocial; they may also be seeking social status and admiration. Indeed, narcissists may use social media for building social capital and for social grooming, especially if it enables them to take advantage of others (Garcia & Sikström, 2014). And if social capital and reward is embodied by the number of likes and retweets one’s tweets typically receives, then narcissists’ self-promoting strategy pays off. Their desire for attention not only explained why they reported receiving more likes and retweets, but also explained why they were more likely to tweet about diet and exercise in both studies. In line with narcissists’ vanity about their appearance (Vazire et al., 2008) and desire for admiration from Twitter followers (Davenport et al., 2014), they may tweet about their diet and exercise routine because they want attention for being physically fit.
Machiavellianism
As predicted, people with Machiavellian traits were more likely to use Twitter than Facebook-only (Study 2), but the data provided few clues to explain Twitter’s appeal for these individuals. Contrary to hypotheses, Machiavellians were not significantly more likely to use Twitter for information-seeking or career promotion, nor did they tweet more frequently about intellectual topics or personal achievements in a purported attempt to impress influential others. If anything, they were less likely to use Twitter for attention-seeking, which explained why they tweeted less frequently about intellectual topics and diet/exercise. Because Machiavellians are concerned with reputational management (Jones & Paulhus, 2014), they may avoid tweeting about topics that have the potential to make them look pretentious or boastful. But this cautious strategy may come at a cost: Their aversion to attention-seeking explained why they received fewer likes/retweets on average to their tweets, suggesting that their low-key presence on Twitter does not generate much social reward. Although these data tell us what does not motivate Machiavellians and what they do not tweet about, the data do not tell us what does motivate them and what they do tweet about. One possibility is that Machiavellians are more likely to use Twitter to keep a cunning eye on friends and enemies alike. Such surveillance may allow them to gather information that is later used for manipulation and to gain social status.
Likability of Tweet Topics
Study 2 revealed that Twitter users most liked to read tweets/retweets about intellectual topics and least liked to read tweets about diet and exercise, consistent with other findings that information-sharing tweets are liked the most and personal tweets the least (Andre et al., 2012). This is not surprising given that Twitter users, on average, were higher in openness than nonusers in Studies 1 and 2, and these were the tweet topics that highly open people liked most and least. These results suggest that highly open people, by gravitating toward Twitter for the intellectual stimulation and career opportunities that it affords, may be influential in setting trends and what is considered popular and entertaining on Twitter. This may be particularly true for “public intellectuals,” actors, musicians, writers, artists, or other celebrities, who tend to amass large numbers of followers and likes/retweets.
If indeed Twitter is the kingdom of the intellectual and creative, then the current results also suggested that it may not be for the diet- and fitness-oriented. Study 2 participants tweeted least frequently about diet/exercise and liked these tweets the least, suggesting that posts about diet and exercise may be received more favorably in a social networking site like Instagram, where the sharing of photos may be more appealing to people concerned with fitness, health, and physical appearance. Paradoxically, however, Study 2 also found that people who frequently tweeted about diet/exercise reported receiving a significantly greater number of likes/retweets. Should not people who post about unpopular topics on Twitter receive fewer, not more, likes and retweets? Although most Twitter users may favor and tweet about intellectual topics, there may be a cadre of individuals from a health and fitness-oriented community who use Twitter to connect with each other and encourage each other’s health-related goals by supplying likes and retweets to each other’s posts. Indeed, tweeting about diet/exercise was predicted by not only attention-seeking motives but also social connection motives. What may matter most, then, is not what topics are deemed most likable by Twitter users in general, but the topics deemed most likable within one’s own social network. Indeed, the various niches within Twitter—for example, those dominated by certain politicians or celebrities—may produce tweets that are only deemed likable by the people within that niche.
Limitations and Future Directions
Although this research had several strengths—notably, that we conducted a preregistered replication of our findings in a different country—it also had several limitations. First, participants self-reported the frequency with which they tweeted about various topics and the number of likes/retweets they received, which may be prone to memory or social desirability biases. In particular, Machiavellians’ concern with reputation management may mean that they downplayed how frequently they tweeted about less socially desirable topics (e.g., diet/exercise), whereas narcissists—who enjoy showing off—may be especially likely to inflate the number of likes/retweets they receive. Future research should code participants’ actual tweets for various topic themes and record the number of likes/retweets for each, then examine associations with personality traits and motives for using Twitter. Further research could also examine whether people who tweet about topics popular within their own social network do indeed receive more likes/retweets, and whether this form of social reward enhances feelings of inclusion and well-being (Tobin et al., 2015). It may be the case that likes/retweets only enhance well-being among Twitter users who crave attention (i.e., narcissists, psychopaths, and introverts).
Second, our measures may require further refinement and expansion. In particular, our measure of informational motives for using Twitter reflected passive consumption of Twitter content rather than active generation. If future versions of this measure included items that reflected more active information exchange on Twitter, such as posting links to news stories, we might find that it is associated with personality traits such as openness. Indeed, we found that openness was significantly associated with career promotion, which tapped more active content generation (e.g., using Twitter to publicize one’s own creative output). Furthermore, it would be useful to measure a wider range of tweet topics. That people with psychopathic and Machiavellian traits are more likely to swear, use negative emotion words, and express anger in their tweets (Preotiuc-Pietro et al., 2017; Sumner et al., 2012) suggests that future research could test the predictors of tweeting about and liking for “darker” topics.
Finally, although we sampled Twitter users from two different countries, they may not be representative of the overall population of Twitter users, just as Twitter users may not be representative of larger populations. Even though we found that Twitter users were higher in openness than Facebook-only users in both samples, the effect sizes were small (rs = .10 and .09 in Studies 1 and 2, respectively) and require further replication in larger and more diverse samples.
Religiosity could be associated with a stronger desire for emotions that strengthen foundational religious beliefs or with a stronger desire for emotions that promote prosocial engagement; it was the first
Religiosity and Desired Emotions: Belief Maintenance or Prosocial Facilitation? Allon Vishkin et al. Personality and Social Psychology Bulletin, January 6, 2020. https://doi.org/10.1177/0146167219895140
Abstract: We assessed how religiosity is related to desired emotions. We tested two competing hypotheses. First, religiosity could be associated with a stronger desire for emotions that strengthen foundational religious beliefs (i.e., more awe and gratitude and less pride). Second, religiosity could be associated with a stronger desire for emotions that promote prosocial engagement (e.g., more love and empathy and less anger and jealousy). Two cross-cultural studies supported the first hypothesis. Religiosity was related to desire for emotions that strengthen religious beliefs, but not to desire for socially engaging or socially disengaging emotions. These findings held across countries and across several different religions. A third study investigating the mechanisms of both hypotheses using structural equation modeling supported only the first hypothesis. This research extends prior work on desired emotions to the domain of religiosity. It demonstrates that the emotions religious people desire may be those that help strengthen their religious beliefs.
Keywords: religion, emotion, emotion regulation
General Discussion
The present investigation examined how religiosity is associated with desired emotions. According to the belief maintenance account, religiosity is associated with desiring
emotions that promote recognition of supernatural beings,
positively for other-praising emotions and negatively for
self-praising emotions. According to the prosocial facilitation account, religiosity is associated with desiring emotions
that promote positive interpersonal functioning, positively
for socially engaging emotions and negatively for socially
disengaging emotions. In two cross-cultural studies, results
supported the belief maintenance account, such that religiosity was associated with a stronger desire for the other-praising emotions of awe and gratitude, a weaker desire for the
self-praising emotion of pride, and no significant association
with a desire for socially engaging or socially disengaging
emotions. These associations held when controlling for emotion experience. They were robust across countries and were
not moderated by religion, with the possible exception of
pride in Study 2. An additional study supported the role of
belief maintenance, but not prosocial facilitation, as the
underlying mechanism of these associations. Overall, the
findings show that people who are more religious value emotions that are consistent with foundational religious beliefs.
Implications for Understanding Religion
and Emotion Regulation
Previous research suggests that religion can influence emotional experience (e.g., Emmons, 2005; Kim-Prieto &
Diener, 2009). Yet little empirical attention has been devoted
to the mechanisms by which religion influences emotional
experience. One such mechanism may involve emotion regulation (for a review, see Vishkin et al., 2014). Religion may
influence emotion regulation, in part, by facilitating the use
of certain emotion regulation strategies. For instance, there is
evidence that religiosity may be linked to the more frequent
use of cognitive reappraisal (Vishkin et al., 2016).
The present study identifies an additional mechanism by
which religiosity may affect emotions—namely, by establishing desired end-states in emotion regulation (see Tamir,
2016). By directing efforts in emotion regulation, desired
end-states in emotion regulation can influence experienced
emotions. Some have suggested that pleasant emotional experiences in religion are the by-product of pursuing personally
meaningful goals (Emmons, 2005). We argue and show that
religiosity is linked not only to what people feel, but also to
what they want to feel—and what they want to feel are emotions that affirm religious beliefs, including more other-praising emotions and less self-praising emotions.
A wide scope of religious behaviors and practices become
de-mystified when understood in terms of the extent to which
they orient people toward or away from emotions that foster
religious beliefs. Contemplation may foster awe (Merton,
2007), daily prayers may foster gratitude (Vishkin et al.,
2014), and placing less emphasis on one’s personal accomplishments may diminish pride. Thus, the desirability of awe,
gratitude, and pride in religion may influence the entire fabric of religious living. Future work should examine the particular mechanisms by which religions shape and sustain
desired emotions.
Implications for Understanding Religion
Some argue that the central tenet of religion is belief in
supernatural beings (e.g., Tylor, 1871). Others argue that the
central tenet of religion is to tie people together in a social
community and strengthen social ties (Graham & Haidt,
2010; Norenzayan & Shariff, 2008). Given that emotions can
help strengthen beliefs as well as social ties, we tested
whether people who are more religious desire emotions that
strengthen the belief in a supernatural being or emotions that
strengthen social ties. We found that when it comes to desiring emotions, more religious people show a stronger desire
for emotions that strengthen beliefs in supernatural beings
but not those that strengthen social ties. We do not rule out
the possibility that at least some aspects of religiosity may
also be linked to desire for socially engaging emotions, as the
results of Study 3 suggest. Future research should continue
to explore this possibility.
Implications for Understanding the Interplay
Between Religion and Culture
In Study 1, the association between religiosity and desire for
pride was weaker in some samples (i.e., the United States,
China, Germany, and Poland) than in others (i.e., Brazil,
Ghana, Israel, and Singapore). In Study 2, the association
between religiosity and desire for pride was weaker in the
United States and Turkey, relative to Israel. The variation in
Study 1 was due specifically to country and not to religion,
whereas in Study 2, country and religion were confounded
and could not be teased apart. This finding suggests that the
link between religiosity and desired emotions may be moderated by country-level norms. One possibility is that strong
norms about pride may override the influence of religiosity
on pride, irrespective of whether the norm is positive or negative. For example, the association between religiosity and
the desire for pride was weaker in the United States (Studies
1 and 2) and Turkey (Study 2) than in other countries. The
positive norm regarding pride in the United States (Mesquita
& Albert, 2007), as well as the norm of honor in Turkey
(Ozgur & Sunar, 1982), may shape the desire for pride in
these countries to such an extent that religiosity will not
influence them. Consistent with this interpretation, in Study
2, pride was desired more in the United States and Turkey
than in Israel.13 Likewise, a strong negative norm regarding
certain types of pride in China (Eid & Diener, 2001) may
have overridden the potential effect of religiosity on pride.
These possibilities, however, await further testing. Indeed,
the numerous possible pairwise comparisons make it difficult to draw strong conclusions, so these differences should
be interpreted with caution.
Studies 1 and 2 were consistent in showing that the effect
of individuals’ particular religion was limited. The associations between religiosity, awe, gratitude, socially engaging
emotions, and socially disengaging emotions in both studies,
and pride in Study 1, held across religions. This suggests that
there may be some common ground in the desirability of certain emotions in different monotheistic religions. In the longstanding debate about whether religions have more in
common (Armstrong, 1994) than differentiates them
(Prothero, 2010), the present findings favor the former view.
However, both the range of religions and the range of emotions that we sampled were limited. Future research could
examine whether idiosyncratic features of particular religions foster different desired emotions.
Limitations and Future Directions
Participants in all studies belonged predominantly (Study 1)
or exclusively (Studies 2 and 3) to monotheistic faiths. We
expect that the pursuit of desired emotions that promote the
recognition of supernatural beings depends on the existence
of supernatural beings within a belief system. However, the
associations between religiosity and desired emotions that
promote religious belief might be stronger the fewer and
more powerful the gods (Big Gods; Norenzayan, 2013). If
so, the associations might be stronger in religions that
endorse the belief in a single god. It remains to be tested
whether these associations replicate in faiths whose formal
theology is not monotheistic.
In addition, the proposed mechanism of belief maintenance was assessed via motivation to be close to god. This
allowed us to directly compare the two motivational
accounts—the desire to be close to god and the desire to be
close to others. Nonetheless, while motivation to be close to
god is a critical component of religious belief, it is not the
only component related to belief maintenance. Moreover, the
proposed mechanisms of belief maintenance and prosocial
facilitation were tested in Study 3 among adherents of a single religion. Given that the same emotion can have different
social implications in cultures higher (vs. lower) in interdependence (Uchida & Kitayama, 2009), the same emotions
may also have different social and religious implications
among adherents of different religions. Therefore, future
research should examine whether belief maintenance also
accounts for the association between religiosity and desired
emotions among adherents of other religions.
In addition, the desire for specific emotions may vary
widely across contexts. The desire for specific emotions
should be greater in contexts where those emotions facilitate
participation in religious events and ceremonies. For
instance, guilt may be more desirable before the Catholic
ritual of confession or during the Jewish day of atonement
(Yom Kippur). Happiness may be more desirable during religious feasts and holidays. It remains to be tested whether the
link between religiosity and desired emotions is moderated
by context.
Religion can be considered as both an individual difference
and a cultural variable (e.g., Gebauer et al., 2012). Accordingly,
there may be two different, but not mutually exclusive, mechanisms by which people who are more religious come to desire
emotions that align with religious beliefs. At the individual
difference level, religious people want to believe in a supernatural being and, in so doing, they may seek emotions that are
instrumental to that belief. At the cultural level, religious cultural institutions provide implicit or explicit instruction that
their members should value awe and gratitude and not necessarily pride, to leverage these emotions to promote religious
beliefs. Future research should examine the manner in which
desired emotions in religion are instilled.
Abstract: We assessed how religiosity is related to desired emotions. We tested two competing hypotheses. First, religiosity could be associated with a stronger desire for emotions that strengthen foundational religious beliefs (i.e., more awe and gratitude and less pride). Second, religiosity could be associated with a stronger desire for emotions that promote prosocial engagement (e.g., more love and empathy and less anger and jealousy). Two cross-cultural studies supported the first hypothesis. Religiosity was related to desire for emotions that strengthen religious beliefs, but not to desire for socially engaging or socially disengaging emotions. These findings held across countries and across several different religions. A third study investigating the mechanisms of both hypotheses using structural equation modeling supported only the first hypothesis. This research extends prior work on desired emotions to the domain of religiosity. It demonstrates that the emotions religious people desire may be those that help strengthen their religious beliefs.
Keywords: religion, emotion, emotion regulation
General Discussion
The present investigation examined how religiosity is associated with desired emotions. According to the belief maintenance account, religiosity is associated with desiring
emotions that promote recognition of supernatural beings,
positively for other-praising emotions and negatively for
self-praising emotions. According to the prosocial facilitation account, religiosity is associated with desiring emotions
that promote positive interpersonal functioning, positively
for socially engaging emotions and negatively for socially
disengaging emotions. In two cross-cultural studies, results
supported the belief maintenance account, such that religiosity was associated with a stronger desire for the other-praising emotions of awe and gratitude, a weaker desire for the
self-praising emotion of pride, and no significant association
with a desire for socially engaging or socially disengaging
emotions. These associations held when controlling for emotion experience. They were robust across countries and were
not moderated by religion, with the possible exception of
pride in Study 2. An additional study supported the role of
belief maintenance, but not prosocial facilitation, as the
underlying mechanism of these associations. Overall, the
findings show that people who are more religious value emotions that are consistent with foundational religious beliefs.
Implications for Understanding Religion
and Emotion Regulation
Previous research suggests that religion can influence emotional experience (e.g., Emmons, 2005; Kim-Prieto &
Diener, 2009). Yet little empirical attention has been devoted
to the mechanisms by which religion influences emotional
experience. One such mechanism may involve emotion regulation (for a review, see Vishkin et al., 2014). Religion may
influence emotion regulation, in part, by facilitating the use
of certain emotion regulation strategies. For instance, there is
evidence that religiosity may be linked to the more frequent
use of cognitive reappraisal (Vishkin et al., 2016).
The present study identifies an additional mechanism by
which religiosity may affect emotions—namely, by establishing desired end-states in emotion regulation (see Tamir,
2016). By directing efforts in emotion regulation, desired
end-states in emotion regulation can influence experienced
emotions. Some have suggested that pleasant emotional experiences in religion are the by-product of pursuing personally
meaningful goals (Emmons, 2005). We argue and show that
religiosity is linked not only to what people feel, but also to
what they want to feel—and what they want to feel are emotions that affirm religious beliefs, including more other-praising emotions and less self-praising emotions.
A wide scope of religious behaviors and practices become
de-mystified when understood in terms of the extent to which
they orient people toward or away from emotions that foster
religious beliefs. Contemplation may foster awe (Merton,
2007), daily prayers may foster gratitude (Vishkin et al.,
2014), and placing less emphasis on one’s personal accomplishments may diminish pride. Thus, the desirability of awe,
gratitude, and pride in religion may influence the entire fabric of religious living. Future work should examine the particular mechanisms by which religions shape and sustain
desired emotions.
Implications for Understanding Religion
Some argue that the central tenet of religion is belief in
supernatural beings (e.g., Tylor, 1871). Others argue that the
central tenet of religion is to tie people together in a social
community and strengthen social ties (Graham & Haidt,
2010; Norenzayan & Shariff, 2008). Given that emotions can
help strengthen beliefs as well as social ties, we tested
whether people who are more religious desire emotions that
strengthen the belief in a supernatural being or emotions that
strengthen social ties. We found that when it comes to desiring emotions, more religious people show a stronger desire
for emotions that strengthen beliefs in supernatural beings
but not those that strengthen social ties. We do not rule out
the possibility that at least some aspects of religiosity may
also be linked to desire for socially engaging emotions, as the
results of Study 3 suggest. Future research should continue
to explore this possibility.
Implications for Understanding the Interplay
Between Religion and Culture
In Study 1, the association between religiosity and desire for
pride was weaker in some samples (i.e., the United States,
China, Germany, and Poland) than in others (i.e., Brazil,
Ghana, Israel, and Singapore). In Study 2, the association
between religiosity and desire for pride was weaker in the
United States and Turkey, relative to Israel. The variation in
Study 1 was due specifically to country and not to religion,
whereas in Study 2, country and religion were confounded
and could not be teased apart. This finding suggests that the
link between religiosity and desired emotions may be moderated by country-level norms. One possibility is that strong
norms about pride may override the influence of religiosity
on pride, irrespective of whether the norm is positive or negative. For example, the association between religiosity and
the desire for pride was weaker in the United States (Studies
1 and 2) and Turkey (Study 2) than in other countries. The
positive norm regarding pride in the United States (Mesquita
& Albert, 2007), as well as the norm of honor in Turkey
(Ozgur & Sunar, 1982), may shape the desire for pride in
these countries to such an extent that religiosity will not
influence them. Consistent with this interpretation, in Study
2, pride was desired more in the United States and Turkey
than in Israel.13 Likewise, a strong negative norm regarding
certain types of pride in China (Eid & Diener, 2001) may
have overridden the potential effect of religiosity on pride.
These possibilities, however, await further testing. Indeed,
the numerous possible pairwise comparisons make it difficult to draw strong conclusions, so these differences should
be interpreted with caution.
Studies 1 and 2 were consistent in showing that the effect
of individuals’ particular religion was limited. The associations between religiosity, awe, gratitude, socially engaging
emotions, and socially disengaging emotions in both studies,
and pride in Study 1, held across religions. This suggests that
there may be some common ground in the desirability of certain emotions in different monotheistic religions. In the longstanding debate about whether religions have more in
common (Armstrong, 1994) than differentiates them
(Prothero, 2010), the present findings favor the former view.
However, both the range of religions and the range of emotions that we sampled were limited. Future research could
examine whether idiosyncratic features of particular religions foster different desired emotions.
Limitations and Future Directions
Participants in all studies belonged predominantly (Study 1)
or exclusively (Studies 2 and 3) to monotheistic faiths. We
expect that the pursuit of desired emotions that promote the
recognition of supernatural beings depends on the existence
of supernatural beings within a belief system. However, the
associations between religiosity and desired emotions that
promote religious belief might be stronger the fewer and
more powerful the gods (Big Gods; Norenzayan, 2013). If
so, the associations might be stronger in religions that
endorse the belief in a single god. It remains to be tested
whether these associations replicate in faiths whose formal
theology is not monotheistic.
In addition, the proposed mechanism of belief maintenance was assessed via motivation to be close to god. This
allowed us to directly compare the two motivational
accounts—the desire to be close to god and the desire to be
close to others. Nonetheless, while motivation to be close to
god is a critical component of religious belief, it is not the
only component related to belief maintenance. Moreover, the
proposed mechanisms of belief maintenance and prosocial
facilitation were tested in Study 3 among adherents of a single religion. Given that the same emotion can have different
social implications in cultures higher (vs. lower) in interdependence (Uchida & Kitayama, 2009), the same emotions
may also have different social and religious implications
among adherents of different religions. Therefore, future
research should examine whether belief maintenance also
accounts for the association between religiosity and desired
emotions among adherents of other religions.
In addition, the desire for specific emotions may vary
widely across contexts. The desire for specific emotions
should be greater in contexts where those emotions facilitate
participation in religious events and ceremonies. For
instance, guilt may be more desirable before the Catholic
ritual of confession or during the Jewish day of atonement
(Yom Kippur). Happiness may be more desirable during religious feasts and holidays. It remains to be tested whether the
link between religiosity and desired emotions is moderated
by context.
Religion can be considered as both an individual difference
and a cultural variable (e.g., Gebauer et al., 2012). Accordingly,
there may be two different, but not mutually exclusive, mechanisms by which people who are more religious come to desire
emotions that align with religious beliefs. At the individual
difference level, religious people want to believe in a supernatural being and, in so doing, they may seek emotions that are
instrumental to that belief. At the cultural level, religious cultural institutions provide implicit or explicit instruction that
their members should value awe and gratitude and not necessarily pride, to leverage these emotions to promote religious
beliefs. Future research should examine the manner in which
desired emotions in religion are instilled.
Smiling as negative feedback affects social decision-making and its neural underpinnings
Smiling as negative feedback affects social decision-making and its neural underpinnings. Martin Weiß, Patrick Mussel & Johannes Hewig. Cognitive, Affective, & Behavioral Neuroscience, Jan 3 2020. https://link.springer.com/article/10.3758/s13415-019-00759-3
Abstract: A crucial aspect of social decision-making is the ability to learn from the outcomes of preceding decisions. In particular, learning might be influenced by the expectedness of feedback and its valence. Expectedness has largely been operationalized as the frequency of stimulus occurrence and not in terms of its social context. Therefore, we investigated the influence of socially unexpected feedback, i.e., smiling upon adverse events, on behavioral and neural responses. We used a modified version of the ultimatum game, a commonly used paradigm for economic decision-making, by implementing different proposer identities with a distinct reaction pattern towards accepted and rejected monetary offers. We could show that an identity, who reacted with a smile towards rejected offers, evoked lower acceptance rates compared to identities, who reward acceptance with a smile. Electrophysiological correlates indicate N170 effects for emotional identities compared to a neutral control identity. Regarding FRN and P3 brain potentials, we detected a particular function of the smiling face when used as a socially unexpected, negative feedback stimulus. Hence, individuals seek an unexpected smile despite the associated monetary loss, which is accompanied by distinct neural patterns.
Abstract: A crucial aspect of social decision-making is the ability to learn from the outcomes of preceding decisions. In particular, learning might be influenced by the expectedness of feedback and its valence. Expectedness has largely been operationalized as the frequency of stimulus occurrence and not in terms of its social context. Therefore, we investigated the influence of socially unexpected feedback, i.e., smiling upon adverse events, on behavioral and neural responses. We used a modified version of the ultimatum game, a commonly used paradigm for economic decision-making, by implementing different proposer identities with a distinct reaction pattern towards accepted and rejected monetary offers. We could show that an identity, who reacted with a smile towards rejected offers, evoked lower acceptance rates compared to identities, who reward acceptance with a smile. Electrophysiological correlates indicate N170 effects for emotional identities compared to a neutral control identity. Regarding FRN and P3 brain potentials, we detected a particular function of the smiling face when used as a socially unexpected, negative feedback stimulus. Hence, individuals seek an unexpected smile despite the associated monetary loss, which is accompanied by distinct neural patterns.
Drug misuse increased since 1995–96 for those with lower socioeconomic status; mental health accounted for only a small part of the increase in misuse; pain explained most of the period trend in misuse of prescription painkillers
Changes in mental health, pain, and drug misuse since the Mid-1990s: Is there a link? Dana A. Glei, Andrew Stokes, Maxine Weinstein. Social Science & Medicine, January 7 2020, 112789, https://doi.org/10.1016/j.socscimed.2020.112789
Highlights
• Drug misuse increased since 1995–96 for those with lower socioeconomic status.
• Except for sedatives, misuse increased more at older than at younger ages.
• Mental health accounted for only a small part of the increase in misuse.
• Pain explained most of the period trend in misuse of prescription painkillers.
• Pain contributed more than mental health to the rise in misuse of all drug types.
Abstract: Drug-related mortality in the US grew dramatically in recent years, while mental health deteriorated among disadvantaged Americans and reported levels of pain increased over the same period. Here we investigate whether increased prevalence of drug misuse between the mid-1990s and early-2010s is associated with higher levels of mental distress and pain. Our results demonstrate higher drug misuse over this period, particularly for older and for socioeconomically disadvantaged Americans. After adjusting for sociodemographic characteristics, we estimate that the prevalence of drug misuse increased by 19 percentage points among those aged 50–76 in the bottom percentile of socioeconomic status (SES). Misuse increased much more at older than at younger ages for all drug types except sedatives, which increased to a similar degree in both age groups. Compared with measures of mental health, pain consistently accounted for a greater share of the period differential in drug misuse among both age groups and across all drug types. Misuse of prescription painkillers exhibited the largest difference in the contributions of pain versus mental health: among older individuals with the lowest SES, pain explained three times as much of the period trend as mental health (60% vs. 19%). Pain was more closely linked with the rise in misuse of prescription painkillers than other drugs. Mental health is a strong correlate of drug misuse (particularly sedative use), but growing drug misuse since the mid-1990s was more strongly linked with rising levels of reported pain than with deterioration in mental health. Pain could be a key factor underlying the association between trends in mental health and drug use: higher levels of pain may contribute to both mental distress and drug misuse. Given that pain, mental distress, and drug misuse are intertwined, successful intervention may require addressing all three factors.
Highlights
• Drug misuse increased since 1995–96 for those with lower socioeconomic status.
• Except for sedatives, misuse increased more at older than at younger ages.
• Mental health accounted for only a small part of the increase in misuse.
• Pain explained most of the period trend in misuse of prescription painkillers.
• Pain contributed more than mental health to the rise in misuse of all drug types.
Abstract: Drug-related mortality in the US grew dramatically in recent years, while mental health deteriorated among disadvantaged Americans and reported levels of pain increased over the same period. Here we investigate whether increased prevalence of drug misuse between the mid-1990s and early-2010s is associated with higher levels of mental distress and pain. Our results demonstrate higher drug misuse over this period, particularly for older and for socioeconomically disadvantaged Americans. After adjusting for sociodemographic characteristics, we estimate that the prevalence of drug misuse increased by 19 percentage points among those aged 50–76 in the bottom percentile of socioeconomic status (SES). Misuse increased much more at older than at younger ages for all drug types except sedatives, which increased to a similar degree in both age groups. Compared with measures of mental health, pain consistently accounted for a greater share of the period differential in drug misuse among both age groups and across all drug types. Misuse of prescription painkillers exhibited the largest difference in the contributions of pain versus mental health: among older individuals with the lowest SES, pain explained three times as much of the period trend as mental health (60% vs. 19%). Pain was more closely linked with the rise in misuse of prescription painkillers than other drugs. Mental health is a strong correlate of drug misuse (particularly sedative use), but growing drug misuse since the mid-1990s was more strongly linked with rising levels of reported pain than with deterioration in mental health. Pain could be a key factor underlying the association between trends in mental health and drug use: higher levels of pain may contribute to both mental distress and drug misuse. Given that pain, mental distress, and drug misuse are intertwined, successful intervention may require addressing all three factors.
Half of the dogs without previous training showed spontaneous rescue behaviors directed to their owners, behavior not motivated by obedience nor by the motivation to re-establish social contact with the owner
Do dogs rescue their owners from a stressful situation? A behavioral and physiological assessment. Fabricio Carballo, Victoria Dzik, Esteban Freidin, Juan Pablo Damián, Emma B. Casanave & Mariana Bentosela. Animal Cognition, Jan 6 2020. https://link.springer.com/article/10.1007/s10071-019-01343-5
Abstract: Rescue behavior is considered a type of pro-social response, defined as a voluntary action directed to benefit another individual who is in a stressful or dangerous situation. In two experiments, we investigated whether dogs would rescue their owners when the person was trapped inside a wooden box and emitted clear signs of stress. The performance of these dogs was compared against that of a control group in which the owners remained calm while trapped. In addition, to assess if training modulated this behavior, we tested a group of dogs from the military trained in search and rescue tasks (Experiment 1). Results showed that dogs opened the box more frequently when the owner pretended to be stressed than when calm. Training shortened latencies to open the door but not the frequency of the behavior. In Experiment 2, we investigated if emotional contagion could be a possible mechanism underlying dogs' rescue responses by measuring dogs’ behavior, heart rate, and saliva cortisol level in the stressed and calm conditions, and also controlled for obedience by having the calm owners call their pets while trapped. We replicated the findings of Experiment 1 as more dogs opened the door in the stressed owner condition than in the calm condition. In addition, we observed an increase in heart rate across trials in the stressed condition and a decrease across trials in the calm condition, but no differences in cortisol levels or stress-related behaviors between conditions. In brief, we found evidence that approximately half of the dogs without previous training showed spontaneous rescue behaviors directed to their owners. Neither was this behavior motivated by obedience nor by the motivation to re-establish social contact with the owner. We conclude that emotional contagion is a plausible mechanism underlying dogs’ rescue behavior in the present protocol.
Abstract: Rescue behavior is considered a type of pro-social response, defined as a voluntary action directed to benefit another individual who is in a stressful or dangerous situation. In two experiments, we investigated whether dogs would rescue their owners when the person was trapped inside a wooden box and emitted clear signs of stress. The performance of these dogs was compared against that of a control group in which the owners remained calm while trapped. In addition, to assess if training modulated this behavior, we tested a group of dogs from the military trained in search and rescue tasks (Experiment 1). Results showed that dogs opened the box more frequently when the owner pretended to be stressed than when calm. Training shortened latencies to open the door but not the frequency of the behavior. In Experiment 2, we investigated if emotional contagion could be a possible mechanism underlying dogs' rescue responses by measuring dogs’ behavior, heart rate, and saliva cortisol level in the stressed and calm conditions, and also controlled for obedience by having the calm owners call their pets while trapped. We replicated the findings of Experiment 1 as more dogs opened the door in the stressed owner condition than in the calm condition. In addition, we observed an increase in heart rate across trials in the stressed condition and a decrease across trials in the calm condition, but no differences in cortisol levels or stress-related behaviors between conditions. In brief, we found evidence that approximately half of the dogs without previous training showed spontaneous rescue behaviors directed to their owners. Neither was this behavior motivated by obedience nor by the motivation to re-establish social contact with the owner. We conclude that emotional contagion is a plausible mechanism underlying dogs’ rescue behavior in the present protocol.
Altered brain network organization in romantic love: Romantic love is a complex state that has been seen as similar to addiction; paper finds decreased overall brain functional segregation
Altered brain network organization in romantic love as measured with resting-state fMRI and graph theory. Chuan Wang et al. Brain Imaging and Behavior, January 2 2020. https://link.springer.com/article/10.1007/s11682-019-00226-0
Abstract: Romantic love is a complex state that has been seen as similar to addiction. Previous task-based functional magnetic resonance imaging (fMRI) studies have shown that being in love is closely associated with functional brain changes in the reward and motivation system. However, romantic love-related functional connectivity network organization in resting-state fMRI has yet to be elucidated. To that end, here we used resting-state fMRI and graph theory to compare whole-brain functional network topology between an “in-love” group (n = 34, 16 females, currently in love and in a romantic relationship) and a “single” group (n = 32, 14 females, never in love and not in a romantic relationship). Compared to the single group, we found lower network segregation in the love group (i.e., lower small-worldness, mean clustering coefficient, and modularity), and these metrics were negatively associated with scores on the Passionate Love Scale (PLS) (an index of intense passionate/romantic love). Additionally, the love group displayed altered connectivity degree (reflecting the importance of a node): decreased degree in left angular gyrus and left medial orbitofrontal cortex, but increased degree in left fusiform gyrus. Furthermore, local efficiency or degree of these regions was significantly correlated to PLS scores. Taken together, results showed decreased overall brain functional segregation but enhanced emotional-social processing in romantic lovers. These findings provide the first evidence of love-related brain network organization changes and suggest similar but different brain network alterations between romantic love and addiction, providing new insights on the neural systems underlying romantic love.
Keywords: Romantic love Resting-state fMRI Graph theory Angular gyrus Fusiform
Abstract: Romantic love is a complex state that has been seen as similar to addiction. Previous task-based functional magnetic resonance imaging (fMRI) studies have shown that being in love is closely associated with functional brain changes in the reward and motivation system. However, romantic love-related functional connectivity network organization in resting-state fMRI has yet to be elucidated. To that end, here we used resting-state fMRI and graph theory to compare whole-brain functional network topology between an “in-love” group (n = 34, 16 females, currently in love and in a romantic relationship) and a “single” group (n = 32, 14 females, never in love and not in a romantic relationship). Compared to the single group, we found lower network segregation in the love group (i.e., lower small-worldness, mean clustering coefficient, and modularity), and these metrics were negatively associated with scores on the Passionate Love Scale (PLS) (an index of intense passionate/romantic love). Additionally, the love group displayed altered connectivity degree (reflecting the importance of a node): decreased degree in left angular gyrus and left medial orbitofrontal cortex, but increased degree in left fusiform gyrus. Furthermore, local efficiency or degree of these regions was significantly correlated to PLS scores. Taken together, results showed decreased overall brain functional segregation but enhanced emotional-social processing in romantic lovers. These findings provide the first evidence of love-related brain network organization changes and suggest similar but different brain network alterations between romantic love and addiction, providing new insights on the neural systems underlying romantic love.
Keywords: Romantic love Resting-state fMRI Graph theory Angular gyrus Fusiform
As found in men, women similarly know how to infer sexual exploitability; unlike men, only some of these cues were associated with short-term attractiveness; so, if a man is too easy, she won't be interested as frequently as men are
Adair, L., Andersen, B., & Hinton, T. (2020). He looks “easy” and she’s not into it: Sexual exploitation cues and attraction. Evolutionary Behavioral Sciences, 14(1), 19–31. Jan 2020. https://doi.org/10.1037/ebs0000168
Abstract: Sexual exploitation research has focused on men as perpetrators of exploitative strategies. To date, the presence and nature of women’s sexually exploitative strategies has not been empirically tested. Replicating the procedure adopted by Goetz, Easton, Lewis, and Buss (2012) using a male-only sample, we examine the relationship between sexual exploitability and attractiveness in a female-only sample. Women (N = 151; 83% White; Mage = 22 years) rated photographs of men displaying various levels of exploitability cues, and then completed the Components of Mate Value Survey and the Sociosexual Orientation Inventory. As found in men, women similarly use cues of incapacitation and manipulability to infer sexual exploitability. However, unlike men, only some of these manipulability cues (those indicating that the man is easily seduced; e.g., flirty, having promiscuous friends) were associated with short-term attractiveness. For women, cues of genetic fitness (e.g., intelligent, facial attractiveness) were associated with short-term attractiveness. Although mate value did not affect these relationships, the relationship between perceived exploitability and short-term attractiveness did depend on sociosexuality. Sexually exploitable targets were perceived as more attractive short-term mates for sexually unrestricted, compared with sexually restricted, women.
Abstract: Sexual exploitation research has focused on men as perpetrators of exploitative strategies. To date, the presence and nature of women’s sexually exploitative strategies has not been empirically tested. Replicating the procedure adopted by Goetz, Easton, Lewis, and Buss (2012) using a male-only sample, we examine the relationship between sexual exploitability and attractiveness in a female-only sample. Women (N = 151; 83% White; Mage = 22 years) rated photographs of men displaying various levels of exploitability cues, and then completed the Components of Mate Value Survey and the Sociosexual Orientation Inventory. As found in men, women similarly use cues of incapacitation and manipulability to infer sexual exploitability. However, unlike men, only some of these manipulability cues (those indicating that the man is easily seduced; e.g., flirty, having promiscuous friends) were associated with short-term attractiveness. For women, cues of genetic fitness (e.g., intelligent, facial attractiveness) were associated with short-term attractiveness. Although mate value did not affect these relationships, the relationship between perceived exploitability and short-term attractiveness did depend on sociosexuality. Sexually exploitable targets were perceived as more attractive short-term mates for sexually unrestricted, compared with sexually restricted, women.
Opinion leaders in Tweeter: Those with stronger motivations to distribute relevant information tended to overestimate their influence in the network
#Opinionleaders: a comparison of self-reported and observable influence of Twitter users. Stephan Winter et al. Information, Communication & Society, Jan 1 2020. https://doi.org/10.1080/1369118X.2019.1705374
ABSTRACT: Social media have become forums of discussions on political and societal debates in which individual users may forward information or influence others. While prior studies either employed network analyses or surveys to identify opinion leaders and their characteristics, the present investigation combines these two approaches to address the relationship between observable and self-perceived influence. For this purpose, a retweet network of Twitter communication on the Brexit debate (N = 15,018) was analyzed in relation to a survey on motives and personality traits that was filled out by a subsample of active users (N = 98). Results showed that users’ eigenvector centrality (as a measure of influence in the network) was significantly related to their political interest and their number of followers, but not to self-perceived opinion leadership. According to a comparison of self-assessment and network position, those with stronger motivations to distribute relevant information tended to overestimate their influence in the network. Implications for the identification of opinion leaders are discussed.
KEYWORDS: Two-step flow, opinion leadership, opinion expression, motivations, network analysis, Twitter
Discussion
The goal of this study was to investigate the characteristics of opinion leaders whose influence can be detected on the basis of observations in contemporary social networks. Furthermore, we aimed to combine prior approaches of survey research and network analyses
(see Kim et al., 2017) in order to compare self-perceptions with more objective data. For
this purpose, we conducted a mixed-method study (a network analysis and survey with a
subsample of the network) with the exemplary case of the Twitter communication regarding the Brexit 2016.
As a measure of observable influence, the present investigation focused on retweets
because this act of passing along information (which is then visible in further users’
feeds) increases the reach of the original message. The measure of eigenvector centrality
(Bonacich, 2007; Dubois & Gaffney, 2014) calculated on the retweet graph captures not
only the number of people who have retweeted one’s original tweets but also how influential the people who further distributed one’s messages are. Results showed that eigenvector centrality was significantly related to political interest (as measured in the
survey). This is in line with prior findings that rendered political interest as a precondition
to actively engage in opinion expression online (e.g., Vraga et al., 2015) and offline (e.g.,
Katz & Lazarsfeld, 1955). The fact that political interest is not only related to self-perceived
influence, as shown in these prior studies, but also to observed influence suggests that
being interested in the domain also makes it more likely that users are able to write tweets
that raise the attention of others. Perhaps these users’ tweets contain higher-quality or
more recent information, which would be a positive outcome for the democratic discourse,
but it is also conceivable that they are more controversial and therefore arouse further
attention. These two opposing assumptions can be tested in future studies that involve
a content analysis of the tweets.
Extraversion and personality strength, which were shown to be predictors of offline
opinion leadership (Gnambs & Batinic, 2012; Weimann, 1991), were not significantly
related to users’ centrality. While extraversion may not be important due to the online
context that may give more opportunities for introverts to carefully prepare their messages, the lack of a relationship with personality strength is in contrast to prior findings
on self-reported opinion leadership in social media (Winter & Neubaum, 2016). Possibly,
this discrepancy can be explained with the more objective measurement and suggests that
personality strength might not serve as a reliable indicator of influence in terms of visibility and reach, at least in this specific debate. However, it has to be noted that persuasive
effects on followers’ attitudes (which are also an integral part of influence) could not be
captured by the present analysis. Thus, the measurement on the basis of retweets may
have overlooked the potential impact that people with high personality strength exert
on others’ attitudes.
With regard to the network structure, eigenvector centrality was positively related to
the number of followers and the number of original tweets a user has generated. In line
with prior research (Xu et al., 2014), these network characteristics can be seen as prerequisites of becoming an opinion leader. While this is unsurprising, the additional influence of
political interest suggests that the potential of a large followership and active posting is
exploited when users are sufficiently knowledgeable in the domain to write messages
that get the attention of others.
In the comparison of self-reports and observed influence, results showed a divergence
between self-perceived opinion leadership and the actual visibility in one’s Twitter network. Although the correlation coefficient was positive, it was rather small in magnitude
and non-significant, which raises the question whether people are able to accurately estimate which impact they have. In most cases, they seem to use the parameters that are
available to them (the number of followers and the number of tweets they generated),
but the further distribution via retweets may be difficult to estimate (experienced Twitter
users may utilize further options of Twitter or monitoring tools for more detailed analyses,
but this is unlikely to be employed by average users). In this stage, it is conceivable that
users with certain characteristics tend to over- or underestimate their influence.
In order to explore these potential biases, we compared the ranks of users according to
their self-perceptions and their more objective influence in terms of eigenvector centrality
(and alternatively the mere number of retweets) and computed a difference score that represents a subjective overestimation of one’s influence. This variable was positively related
with personality strength, suggesting that those who perceive themselves as charismatic
may not always be accurate in their estimation of influence. Although personality strength
has been regarded as a direct measurement of opinion leadership in prior research (e.g.,
Schenk & Rössler, 1997; Shah & Scheufele, 2006), this may raise questions on how suitable
the personality strength scale is when it comes to assess a person’s reach in the online context; however, it has to be noted that results only showed a marginally significant relation
for the index based on eigenvector centrality (and a significant relation in the alternative
analysis based on the number of retweets). Additionally, the extent to which users are
motivated to distribute relevant information was significantly related to an overestimation:
Although this motive may spur users’ activity (Winter & Neubaum, 2016), it appears that
users might be overly optimistic and that their goals of informing others about public
affairs are not always reached. One explanation could be that users who are driven by
the motive of informing others might be inclined to post more factual information,
while those who wish to persuade make use of emotional appeals. Emotional messages
have been shown to be more likely to be shared or reacted to on social media in various
settings (Stieglitz & Dang-Xuan, 2013). However, this explanation has to be tested in
future studies.
In the interpretation of results, the following limitations have to be kept in mind. First,
the present investigation focused on eigenvector centrality as an indicator of visibility and
reach in the network, which is an important aspect of opinion leadership but, as mentioned above, does not cover the actual persuasive influence (Robinson, 1976). Thereby,
the self-perception measurement included a more extensive understanding of influence,
while the analysis was only able to focus on observable quantitative aspects. Future studies
could therefore also employ ratings by other users (Schenk & Rössler, 1997) to assess how
a specific user is regarded by followers and how her/his content leads to actual attitude
change. Second, the analysis did not consider the content of the messages. A next step
for future research could be to investigate whether messages with a greater reach and visibility differentiate from those that do not get as much attention (for instance, are opinion
leaders’ tweets more accurate since these people are more politically interested?). Third,
the survey data is limited by the small sample size. Due to the restrictions of sending messages to Twitter users, the recruitment procedure turned out to be more challenging than
expected and resulted in a low response rate and thus in a relatively small sample.
Furthermore, it is likely that those who decided to take part in the survey were more interested in the topic (results showed a high level of political interest in the sample). Comparing the methods of inviting users publicly versus privately, direct messages led to a higher
turnout, which could be considered in the recruitment for similar studies. Finally, the
community of Twitter users may have particularities that do not apply to the general
population (for instance, Hölig (2018) showed that German Twitter users are more extraverted and report higher personality strength than average Internet users). Thus, the
findings warrant replication with different groups, topics, and platforms.
Despite these limitations, we argue that the present study demonstrates the need for
combined approaches of computer science and social science methods to get further
insights into the characteristics of opinion leadership in social media. The unprecedented
combination of behavioral and survey data indicates a gap between self-perceived opinion
leadership and people’s observable influence in the network. Since Twitter users may not
have knowledge about whether they have successfully passed along information or persuaded others, Twitter users take the mere quantity of followers and posting activities
as a proxy to assess their potential influence. The divergence between self-perceived
opinion leadership and observable influence in terms of reach appears to be fueled by
people’s personality strength and their motivation to distribute relevant information.
These factors seem to lead to an overstatement, indicating that those factors that were proposed to drive opinion expression may also be the variables which dilute the accuracy of
self-reports on online influence.
ABSTRACT: Social media have become forums of discussions on political and societal debates in which individual users may forward information or influence others. While prior studies either employed network analyses or surveys to identify opinion leaders and their characteristics, the present investigation combines these two approaches to address the relationship between observable and self-perceived influence. For this purpose, a retweet network of Twitter communication on the Brexit debate (N = 15,018) was analyzed in relation to a survey on motives and personality traits that was filled out by a subsample of active users (N = 98). Results showed that users’ eigenvector centrality (as a measure of influence in the network) was significantly related to their political interest and their number of followers, but not to self-perceived opinion leadership. According to a comparison of self-assessment and network position, those with stronger motivations to distribute relevant information tended to overestimate their influence in the network. Implications for the identification of opinion leaders are discussed.
KEYWORDS: Two-step flow, opinion leadership, opinion expression, motivations, network analysis, Twitter
Discussion
The goal of this study was to investigate the characteristics of opinion leaders whose influence can be detected on the basis of observations in contemporary social networks. Furthermore, we aimed to combine prior approaches of survey research and network analyses
(see Kim et al., 2017) in order to compare self-perceptions with more objective data. For
this purpose, we conducted a mixed-method study (a network analysis and survey with a
subsample of the network) with the exemplary case of the Twitter communication regarding the Brexit 2016.
As a measure of observable influence, the present investigation focused on retweets
because this act of passing along information (which is then visible in further users’
feeds) increases the reach of the original message. The measure of eigenvector centrality
(Bonacich, 2007; Dubois & Gaffney, 2014) calculated on the retweet graph captures not
only the number of people who have retweeted one’s original tweets but also how influential the people who further distributed one’s messages are. Results showed that eigenvector centrality was significantly related to political interest (as measured in the
survey). This is in line with prior findings that rendered political interest as a precondition
to actively engage in opinion expression online (e.g., Vraga et al., 2015) and offline (e.g.,
Katz & Lazarsfeld, 1955). The fact that political interest is not only related to self-perceived
influence, as shown in these prior studies, but also to observed influence suggests that
being interested in the domain also makes it more likely that users are able to write tweets
that raise the attention of others. Perhaps these users’ tweets contain higher-quality or
more recent information, which would be a positive outcome for the democratic discourse,
but it is also conceivable that they are more controversial and therefore arouse further
attention. These two opposing assumptions can be tested in future studies that involve
a content analysis of the tweets.
Extraversion and personality strength, which were shown to be predictors of offline
opinion leadership (Gnambs & Batinic, 2012; Weimann, 1991), were not significantly
related to users’ centrality. While extraversion may not be important due to the online
context that may give more opportunities for introverts to carefully prepare their messages, the lack of a relationship with personality strength is in contrast to prior findings
on self-reported opinion leadership in social media (Winter & Neubaum, 2016). Possibly,
this discrepancy can be explained with the more objective measurement and suggests that
personality strength might not serve as a reliable indicator of influence in terms of visibility and reach, at least in this specific debate. However, it has to be noted that persuasive
effects on followers’ attitudes (which are also an integral part of influence) could not be
captured by the present analysis. Thus, the measurement on the basis of retweets may
have overlooked the potential impact that people with high personality strength exert
on others’ attitudes.
With regard to the network structure, eigenvector centrality was positively related to
the number of followers and the number of original tweets a user has generated. In line
with prior research (Xu et al., 2014), these network characteristics can be seen as prerequisites of becoming an opinion leader. While this is unsurprising, the additional influence of
political interest suggests that the potential of a large followership and active posting is
exploited when users are sufficiently knowledgeable in the domain to write messages
that get the attention of others.
In the comparison of self-reports and observed influence, results showed a divergence
between self-perceived opinion leadership and the actual visibility in one’s Twitter network. Although the correlation coefficient was positive, it was rather small in magnitude
and non-significant, which raises the question whether people are able to accurately estimate which impact they have. In most cases, they seem to use the parameters that are
available to them (the number of followers and the number of tweets they generated),
but the further distribution via retweets may be difficult to estimate (experienced Twitter
users may utilize further options of Twitter or monitoring tools for more detailed analyses,
but this is unlikely to be employed by average users). In this stage, it is conceivable that
users with certain characteristics tend to over- or underestimate their influence.
In order to explore these potential biases, we compared the ranks of users according to
their self-perceptions and their more objective influence in terms of eigenvector centrality
(and alternatively the mere number of retweets) and computed a difference score that represents a subjective overestimation of one’s influence. This variable was positively related
with personality strength, suggesting that those who perceive themselves as charismatic
may not always be accurate in their estimation of influence. Although personality strength
has been regarded as a direct measurement of opinion leadership in prior research (e.g.,
Schenk & Rössler, 1997; Shah & Scheufele, 2006), this may raise questions on how suitable
the personality strength scale is when it comes to assess a person’s reach in the online context; however, it has to be noted that results only showed a marginally significant relation
for the index based on eigenvector centrality (and a significant relation in the alternative
analysis based on the number of retweets). Additionally, the extent to which users are
motivated to distribute relevant information was significantly related to an overestimation:
Although this motive may spur users’ activity (Winter & Neubaum, 2016), it appears that
users might be overly optimistic and that their goals of informing others about public
affairs are not always reached. One explanation could be that users who are driven by
the motive of informing others might be inclined to post more factual information,
while those who wish to persuade make use of emotional appeals. Emotional messages
have been shown to be more likely to be shared or reacted to on social media in various
settings (Stieglitz & Dang-Xuan, 2013). However, this explanation has to be tested in
future studies.
In the interpretation of results, the following limitations have to be kept in mind. First,
the present investigation focused on eigenvector centrality as an indicator of visibility and
reach in the network, which is an important aspect of opinion leadership but, as mentioned above, does not cover the actual persuasive influence (Robinson, 1976). Thereby,
the self-perception measurement included a more extensive understanding of influence,
while the analysis was only able to focus on observable quantitative aspects. Future studies
could therefore also employ ratings by other users (Schenk & Rössler, 1997) to assess how
a specific user is regarded by followers and how her/his content leads to actual attitude
change. Second, the analysis did not consider the content of the messages. A next step
for future research could be to investigate whether messages with a greater reach and visibility differentiate from those that do not get as much attention (for instance, are opinion
leaders’ tweets more accurate since these people are more politically interested?). Third,
the survey data is limited by the small sample size. Due to the restrictions of sending messages to Twitter users, the recruitment procedure turned out to be more challenging than
expected and resulted in a low response rate and thus in a relatively small sample.
Furthermore, it is likely that those who decided to take part in the survey were more interested in the topic (results showed a high level of political interest in the sample). Comparing the methods of inviting users publicly versus privately, direct messages led to a higher
turnout, which could be considered in the recruitment for similar studies. Finally, the
community of Twitter users may have particularities that do not apply to the general
population (for instance, Hölig (2018) showed that German Twitter users are more extraverted and report higher personality strength than average Internet users). Thus, the
findings warrant replication with different groups, topics, and platforms.
Despite these limitations, we argue that the present study demonstrates the need for
combined approaches of computer science and social science methods to get further
insights into the characteristics of opinion leadership in social media. The unprecedented
combination of behavioral and survey data indicates a gap between self-perceived opinion
leadership and people’s observable influence in the network. Since Twitter users may not
have knowledge about whether they have successfully passed along information or persuaded others, Twitter users take the mere quantity of followers and posting activities
as a proxy to assess their potential influence. The divergence between self-perceived
opinion leadership and observable influence in terms of reach appears to be fueled by
people’s personality strength and their motivation to distribute relevant information.
These factors seem to lead to an overstatement, indicating that those factors that were proposed to drive opinion expression may also be the variables which dilute the accuracy of
self-reports on online influence.
Breastfeeding: Feminists have aligned themselves on both sides of this issue; we find support for breastfeeding as an intrasexual domain for signaling one’s social status and resources
Volk, A. A., & Franklin, P. (2020). When is the breast best? Infant feeding as a domain of intrasexual competition. Evolutionary Behavioral Sciences, 14(1), 6–18. Jan 2020. https://doi.org/10.1037/ebs0000167
Abstract: Medical science is unanimous in stating the numerous and significant benefits (to child and mother) of breastfeeding. Breastfeeding is free and is biologically plausible for most mothers. Yet a significant percentage of mothers do not breastfeed their infants. Feminist theorists have aligned themselves on both sides of this issue (as well as the fence in between). Some view breastfeeding as an inherently natural and empowering aspect of femininity. Others view it as a means of suppressing women’s choices and belittling their contributions. We suggest that one reason for this controversy is that breastfeeding may be about more than just providing nutrition to one’s infant. Breastfeeding may also represent a domain of female intrasexual competition. We review evidence from modern developed and developing countries, historical countries, and hunter–gatherer cultures and find it consistent with our hypothesis. Specifically, wealthy women in developed countries tend to have fewer children yet flaunt their breastfeeding as a display of their resources whereas wealthy women in developing/historical countries tend to demonstrate their resources by focusing on having more children and avoiding breastfeeding. We therefore find support for breastfeeding as an intrasexual domain for signaling one’s social status and resources. Given this variation in breastfeeding practices, we argue that breastfeeding is an agentic expression of women’s proximate and evolved psychological decisions and advocate for providing supports that allow women to freely make the best decisions for themselves.
Public Significance Statement—Our research examines why there has been conflicting views of breastfeeding from varying feminist perspectives. We suggest that breastfeeding may represent more than simply the feeding of one’s infant. It may also represent a potential form of intrasexual competition between women. We argue for providing women supports that allow them to freely make the best decisions for themselves regarding breastfeeding choices.
Abstract: Medical science is unanimous in stating the numerous and significant benefits (to child and mother) of breastfeeding. Breastfeeding is free and is biologically plausible for most mothers. Yet a significant percentage of mothers do not breastfeed their infants. Feminist theorists have aligned themselves on both sides of this issue (as well as the fence in between). Some view breastfeeding as an inherently natural and empowering aspect of femininity. Others view it as a means of suppressing women’s choices and belittling their contributions. We suggest that one reason for this controversy is that breastfeeding may be about more than just providing nutrition to one’s infant. Breastfeeding may also represent a domain of female intrasexual competition. We review evidence from modern developed and developing countries, historical countries, and hunter–gatherer cultures and find it consistent with our hypothesis. Specifically, wealthy women in developed countries tend to have fewer children yet flaunt their breastfeeding as a display of their resources whereas wealthy women in developing/historical countries tend to demonstrate their resources by focusing on having more children and avoiding breastfeeding. We therefore find support for breastfeeding as an intrasexual domain for signaling one’s social status and resources. Given this variation in breastfeeding practices, we argue that breastfeeding is an agentic expression of women’s proximate and evolved psychological decisions and advocate for providing supports that allow women to freely make the best decisions for themselves.
Public Significance Statement—Our research examines why there has been conflicting views of breastfeeding from varying feminist perspectives. We suggest that breastfeeding may represent more than simply the feeding of one’s infant. It may also represent a potential form of intrasexual competition between women. We argue for providing women supports that allow them to freely make the best decisions for themselves regarding breastfeeding choices.
Female authors created female heroes who were more likely to be human girls without superhuman abilities, while males created female heroes who were unlikely to be fully human
Ingalls, V. (2020). Who creates warrior women? An investigation of the warrior characteristics of fictional female heroes based on the sex of the author. Evolutionary Behavioral Sciences, 14(1), 79–91. Jan 2020. https://doi.org/10.1037/ebs0000176
Abstract: Previous research has found that the sex of the author can influence the characteristics of their fictional hero and that these differences can be predicted using evolutionary psychology. According to sexual selection theory, males and females evolve different behavioral strategies, and thus different psychologies, in order to maximize reproductive success; thus, humans will have behavioral tendencies influenced by subconscious mechanisms that would have aided fitness in the ancestral environment. This study focuses on how the characteristics of the female hero may differ based on the sex of the author using 30 fantasy series written for children ages 10–17. Male authors are predicted to create female heroes who are more physically powerful and more likely to engage in physical conflicts than female authors, because males benefit more than females from physical battle. Although not all comparisons produced statistically significant differences, all data produced trends in the predicted directions. A closer analysis found that female authors created female heroes who were more likely to be human girls without superhuman abilities, while males created female heroes who were unlikely to be fully human. When examining male–female hero teams, it was found that female authors tended to make the male hero more powerful than his female teammate, which was not true for male authors. This may be because females benefit when their mate can dominate other males. These results suggest that males and females create different traits in their heroes, irrespective of the hero’s sex, and that female-created heroes achieve their goals without resorting to physical violence.
Abstract: Previous research has found that the sex of the author can influence the characteristics of their fictional hero and that these differences can be predicted using evolutionary psychology. According to sexual selection theory, males and females evolve different behavioral strategies, and thus different psychologies, in order to maximize reproductive success; thus, humans will have behavioral tendencies influenced by subconscious mechanisms that would have aided fitness in the ancestral environment. This study focuses on how the characteristics of the female hero may differ based on the sex of the author using 30 fantasy series written for children ages 10–17. Male authors are predicted to create female heroes who are more physically powerful and more likely to engage in physical conflicts than female authors, because males benefit more than females from physical battle. Although not all comparisons produced statistically significant differences, all data produced trends in the predicted directions. A closer analysis found that female authors created female heroes who were more likely to be human girls without superhuman abilities, while males created female heroes who were unlikely to be fully human. When examining male–female hero teams, it was found that female authors tended to make the male hero more powerful than his female teammate, which was not true for male authors. This may be because females benefit when their mate can dominate other males. These results suggest that males and females create different traits in their heroes, irrespective of the hero’s sex, and that female-created heroes achieve their goals without resorting to physical violence.
Twin studies showed evidence for genetic effects on values; heritability influence values to a greater extent than the shared environment; shared environment was more relevant to self-enhancement & openness to change than to other values
Beyond culture and the family: Evidence from twin studies on the genetic and environmental contribution to values. Louise Twito, Ariel Knafo-Noam. Neuroscience & Biobehavioral Reviews, January 7 2020. https://doi.org/10.1016/j.neubiorev.2019.12.029
Highlights
• We reviewed twin studies on human values.
• All studies showed evidence for genetic effects on values, as well as non-shared environment contributions.
• Heritability influence values to a greater extent than the shared environment.
• The shared environment was more relevant to self-enhancement and openness to change than to other values.
• We discuss findings in light of family value socialization processes.
Abstract: Human values are abstract goals, affecting decisions, choices and behavior (Schwartz, 1992). Despite much value research, there is a lack of research on the etiology of values, specifically potential genetic influences. We therefore reviewed all published twin studies on human values, classified as representing four higher order values across two bipolar dimensions: Self-transcendence versus Self-enhancement and Openness to change versus Conservation. Across most studies, and most values, monozygotic twins correlated more strongly than dizygotic twins, indicating genetic contribution to values. Significant heritability estimates ranged from 24.5 to 85.7%. The effects of the environment shared by family members were generally weaker. Finally, there was a contribution of the non-shared environment for all values. After discussing the implications for the neuropsychological research on values, we suggest several future research directions, which may help guide the future science of the etiology of values. We also discuss the possible discrepancy between our findings and theory and research on value socialization and discuss the interplay of genes and the environment in the development of values.
Highlights
• We reviewed twin studies on human values.
• All studies showed evidence for genetic effects on values, as well as non-shared environment contributions.
• Heritability influence values to a greater extent than the shared environment.
• The shared environment was more relevant to self-enhancement and openness to change than to other values.
• We discuss findings in light of family value socialization processes.
Abstract: Human values are abstract goals, affecting decisions, choices and behavior (Schwartz, 1992). Despite much value research, there is a lack of research on the etiology of values, specifically potential genetic influences. We therefore reviewed all published twin studies on human values, classified as representing four higher order values across two bipolar dimensions: Self-transcendence versus Self-enhancement and Openness to change versus Conservation. Across most studies, and most values, monozygotic twins correlated more strongly than dizygotic twins, indicating genetic contribution to values. Significant heritability estimates ranged from 24.5 to 85.7%. The effects of the environment shared by family members were generally weaker. Finally, there was a contribution of the non-shared environment for all values. After discussing the implications for the neuropsychological research on values, we suggest several future research directions, which may help guide the future science of the etiology of values. We also discuss the possible discrepancy between our findings and theory and research on value socialization and discuss the interplay of genes and the environment in the development of values.
Monday, January 6, 2020
Waist to hip ratio and breast size modulate the processing of female body silhouettes: An EEG study
Waist to hip ratio and breast size modulate the processing of female body silhouettes: An EEG study. Farid Pazhoohi, Joana Arantes, Alan Kingstone, Diego Pinal. Evolution and Human Behavior, January 7 2020. https://doi.org/10.1016/j.evolhumbehav.2020.01.001
Abstract: Waist-to-hip ratio (WHR) and breast size are considered important biological features defining female body attractiveness; but their neurophysiological correlates remain largely unknown. To shed light on this issue, behavioral and electroencephalographic responses were recorded while healthy heterosexual men and women completed an oddball task, which was then followed by an attractiveness judgement task. In both cases participants were presented with female body forms that combined 0.6, 0.7 or 0.8 WHRs with small or large breast sizes. Brain activity dynamics were explored using temporal principal component analysis of the event-related potentials data. Variance in the data was explained mostly by eight temporal factors for the oddball task and six for the attractiveness judgement task. Lower WHRs seemed to gather larger processing resources than higher WHRs at early perceptual-related processes during the oddball task. The less attractive WHRs and breast sizes, in contrast, seemed to boost allocation of resources later in the processing stream, which may be due to a negativity bias enhancing evaluation and decision-making processes. This inference is supported by results from the attractiveness judgement task, although the observer's gender may also play a role. Finally, LORETA analysis of the temporal factors indicate that variations in WHR may modulate activation of frontal regions, such as the anterior cingulate and orbitofrontal cortex, that are related with reward processing and decision-making; while variations in breast size may influence activity in posterior parietal regions involved in human body perception. This paper highlights the biological importance of female body physical features in defining attractiveness, and the neurophysiological correlates that are implicated.
Keywords: Waist to hip ratioBreast sizeAttractivenessNeural correlatesEEG
Men looking at women... The contrapposto pose was perceived as more attractive than the standing pose:
Behavioral display of lumbar curvature in response to the opposite sex. Zeynep Şenveli Bilkent University, Graduate Program in Neuroscience - Master's degree thesis. https://www.bipartisanalliance.com/2017/08/behavioral-display-of-lumbar-curvature.html
Abstract: Waist-to-hip ratio (WHR) and breast size are considered important biological features defining female body attractiveness; but their neurophysiological correlates remain largely unknown. To shed light on this issue, behavioral and electroencephalographic responses were recorded while healthy heterosexual men and women completed an oddball task, which was then followed by an attractiveness judgement task. In both cases participants were presented with female body forms that combined 0.6, 0.7 or 0.8 WHRs with small or large breast sizes. Brain activity dynamics were explored using temporal principal component analysis of the event-related potentials data. Variance in the data was explained mostly by eight temporal factors for the oddball task and six for the attractiveness judgement task. Lower WHRs seemed to gather larger processing resources than higher WHRs at early perceptual-related processes during the oddball task. The less attractive WHRs and breast sizes, in contrast, seemed to boost allocation of resources later in the processing stream, which may be due to a negativity bias enhancing evaluation and decision-making processes. This inference is supported by results from the attractiveness judgement task, although the observer's gender may also play a role. Finally, LORETA analysis of the temporal factors indicate that variations in WHR may modulate activation of frontal regions, such as the anterior cingulate and orbitofrontal cortex, that are related with reward processing and decision-making; while variations in breast size may influence activity in posterior parietal regions involved in human body perception. This paper highlights the biological importance of female body physical features in defining attractiveness, and the neurophysiological correlates that are implicated.
Keywords: Waist to hip ratioBreast sizeAttractivenessNeural correlatesEEG
Men looking at women... The contrapposto pose was perceived as more attractive than the standing pose:
Waist-to-Hip Ratio as Supernormal Stimuli: Effect of Contrapposto Pose and Viewing Angle. Farid Pazhoohi. Archives of Sexual Behavior, June 18 2019. https://www.bipartisanalliance.com/2019/06/men-looking-at-women-contrapposto-pose.html
Behavioral display of lumbar curvature in response to the opposite sex. Zeynep Şenveli Bilkent University, Graduate Program in Neuroscience - Master's degree thesis. https://www.bipartisanalliance.com/2017/08/behavioral-display-of-lumbar-curvature.html
Reaching Further Back in Evolutionary Time for the Origins of REM Sleep: Lizards have it too
What Is REM Sleep? Mark S. Blumberg et al. Current Biology, Volume 30, Issue 1, 6 January 2020, Pages R38-R49. https://doi.org/10.1016/j.cub.2019.11.045
For many decades, sleep researchers have sought to determine which species ‘have’ rapid eye movement (REM) sleep. In doing so, they relied predominantly on a template derived from the expression of REM sleep in the adults of a small number of mammalian species. Here, we argue for a different approach that focuses less on a binary decision about haves and have nots, and more on the diverse expression of REM sleep components over development and across species. By focusing on the components of REM sleep and discouraging continued reliance on a restricted template, we aim to promote a richer and more biologically grounded developmental–comparative approach that spans behavioral, physiological, neural, and ecological domains.
For many decades, sleep researchers have sought to determine which species ‘have’ rapid eye movement (REM) sleep. In doing so, they relied predominantly on a template derived from the expression of REM sleep in the adults of a small number of mammalian species. Here, we argue for a different approach that focuses less on a binary decision about haves and have nots, and more on the diverse expression of REM sleep components over development and across species. By focusing on the components of REM sleep and discouraging continued reliance on a restricted template, we aim to promote a richer and more biologically grounded developmental–comparative approach that spans behavioral, physiological, neural, and ecological domains.
Reaching Further Back in Evolutionary Time for the Origins of REM Sleep
There is broad consensus today that both mammals and birds
exhibit REM sleep. If this consensus is correct, we would next
want to know how the similar sleep patterns in such distantly
related groups evolved. Mammals and birds have not shared a
common ancestor for over 300 million years. Did REM sleep
evolve independently in the mammalian and avian lineages, or
was REM sleep present in a common ancestor? Researchers
have long tried to answer this question by recording sleep
behavior and brain activity in non-avian reptiles, amphibians,
and fishes. Unfortunately, this work has often yielded contradictory results [110–112].
Two recent studies in lizards suggest that contradictions in the
earlier literature reflect genuine diversity in the way sleep manifests across reptiles. Shein-Idelson and colleagues [18] recently
reported the existence of REM sleep in the Australian bearded
dragon. Brain activity in this sleeping lizard alternates with astonishing regularity — every 80 seconds — between equal-length
periods composed of sharp waves and wake-like brain activity
with isolated eye movements (called ‘eye twitches’) under closed
eyelids. Limb twitches were not reported. Shortly after this initial
description of REM-like sleep in the dragon, these findings were
replicated in the same species by another research group [113].
This second team also found that another lizard, the tegu (Salvator merianae), exhibits a REM-like sleep state, including distinct
brain activity associated with eye movements (rare limb twitches
were observed but were not unambiguously related to the state).
However, the two species showed marked differences in the
REM-like sleep state. Whereas brain activity in the dragon was
characterized by high power across a broad range of frequencies (10–30 Hz), similar to that observed during wakefulness, brain activity in the tegu exhibited a distinct 15-Hz peak
not found during wake. Moreover, in contrast to the precisely
regular alternation between sleep states in dragons, tegus
showed no such regularity.
Although the reasons for the stark differences in the two lizards
are unknown, the studies further underscore the challenge of
finding consensus on the defining features of REM sleep: if these
two lizard species exhibit such diversity, what should we expect
as more reptiles are studied? Will their sleep patterns converge
on a shared set of characteristics that resemble REM sleep in
mammals and birds? And how should we interpret previous
studies that failed to detect a REM-like state in crocodilians,
the closest living relatives to birds, and in turtles, the sister
group to birds and crocodilians [110,111]? Although it is possible
that the earlier studies in crocodilians and turtles were somehow
flawed, we should not simply ignore these exceptions. In the
end, when attempting to trace the evolution of REM sleep, we
must account for the full taxonomic diversity of sleep and its
seemingly patchy phylogenetic distribution.
But now, again, yet another recent paper claims to have
pushed the evolutionary origins of REM and non-REM sleep
even further back in time — to 450 million years ago. Using
larval zebrafish (Danio rerio), Leung and colleagues [9] developed an impressive whole-body fluorescence method to measure neural activity throughout the brain of these transparent
animals while restrained in agar. In addition to brain activity,
they measured muscle activity, eye movements, and heart
rate. Two sleep states were reported: the first state, most
clearly defined after sleep deprivation, is characterized by
synchronous bursts of activity alternating with periods of
silence in the dorsal pallium (a homologue of neocortex), reminiscent of the bursts of activity during mammalian and avian
non-REM sleep (albeit on a much slower timescale). The onset
of the second spontaneous state is characterized by a single
contraction of the trunk muscles lasting 10–15 seconds and a
single, prolonged (up to 5 min) burst of activity that propagates
through the central nervous system. The authors call this state
propagating wave sleep (PWS). It should be noted that the longlasting muscle contractions that occur at the onset of brain
activation are unlike the brief twitches that characterize
mammalian REM sleep. Also, brain activity after a burst in the
zebrafish was suppressed below waking levels for more than
20 minutes. Another peculiarity is that rapid eye movements
did not occur during spontaneous PWS, even though the eyes
moved freely during wakefulness. Thus, although these bursts
of activation are fascinating, it is unclear if and how they relate
to REM sleep in mammals and birds.
Additional hints suggest that components of REM sleep
emerged even farther back in evolutionary time. For example,
a variety of insects — from larval flies to adult bees — twitch their
antennae during states that resemble sleep [114–117]. But such
observations alone do not constitute clear evidence of homology
between invertebrate and vertebrate sleep states. After all, not all
movements during sleep are twitches; nor do we have sufficient
information about the nervous systems of sleeping insects to understand what these twitch-like movements represent.
Twitching is also apparent in resting cuttlefish (Sepia officinalis), but in a way that is remarkable and unique. When awake and
swimming, cuttlefish exhibit choreographed patterns of coloration for communication and camouflage [118]. The changes
in color and pattern are mediated by chromatophores —
pigment-containing skin cells that are controlled by striated
muscle. While apparently asleep, cuttlefish initially rest motionless on the seafloor with their pupils constricted and their coloration cryptically matching the surrounding substrate [119,120].
Such periods of quiet rest are occasionally interrupted by prolonged (2–3 minute) bouts of twitching of the tentacles, eyes,
and — astoundingly — the chromatophores, resulting in rapid
changes in coloration and patterning that announce, rather
than conceal, their presence (similar patterns of chromatophore
activation during apparent sleep have been reported in the
octopus [121,122]). Although arousal thresholds have not been
assessed to rule out the possibility that the cuttlefish behaviors
reflect brief awakenings, the patterns of chromatophore activation bear little resemblance to what is observed when cuttlefish
are clearly awake. If, in fact, they are asleep, further work on cuttlefish may provide novel insights into the evolution of REM-like
sleep states, especially given the independent evolution of complex brains, behavior, and cognition in cephalopods [123]. When
combined with research on relatively ‘simple’ mollusks [124], this
research raises the hope of revealing the independent and
convergent evolution of individual components that comprise
REM sleep.
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