Wednesday, February 19, 2020

Decreasing use of counting & increasing use of direct retrieval & derived facts through years 1–4, girls using counting substantially more and the other two strategies substantially less than boys

Sex differences in mental strategies for single-digit addition in the first years of school. Pernille B. Sunde, Peter Sunde & Judy Sayers. Educational Psychology, An International Journal of Experimental Educational Psychology. Volume 40, 2020 - Issue 1, Pages 82-102.

Abstract: Strategy use in single-digit addition is an indicator of young children’s numeracy comprehension. We investigated Danish primary students’ use of strategies in single-digit addition with interview-based assessment of how they solved 36 specific single-digit addition problems, categorised as either ‘error’, ‘counting’, ‘direct retrieval’ or ‘derived facts’. The proportional use of each strategy was analysed as multi-level functions of school age and sex. In a first study (260 interviews, 147 students) we found decreasing use of counting and increasing use of direct retrieval and derived facts through years 1–4, girls using counting substantially more and the other two strategies substantially less than boys, equal to more than 2 years’ development. Similar results appeared in a subsequent study (155 interviews, 83 students), suggesting that the pattern is pervasive in Danish primary schools. Finally, we ask whether sex differences in strategy use is generally under-reported since many studies do not explicitly address them.

Keywords: Sex differences, single-digit addition, strategies, years 1–4, mathematics

The marked sex-difference in development of strategy may have implications for research as well as teaching practice. Regarding research of variation and development of strategy use, our results suggest that sex may be a significant component of variation that should not only be tested for (or neutralised by balanced study designs), but incorporated in the statistical analyses instead of appearing as apparent statistical background noise. Sex differences in strategy use (or any other behaviour or skill) may also be of interest in its own right in order to identify differences between boys and girls in a given age or cultural context. For teaching practice, knowledge of the existence of substantial variation in different students’ development of strategy use, much of which connecting to the individual’s sex may also be of importance. For instance, students who overly rely on counting in single-digit problem solving (of which girls are overrepresented) may need explicit teaching and encouragement to memorise number facts and patterns in number bonds. Thus, if instruction in the early years of school focus on counting strategies and procedural knowledge in the teaching of arithmetic this would disadvantage the girls as they are more prone to construct narrow knowledge and rely on the taught algorithms (Hornburg et al., 2017). Furthermore, Laski et al. (2013) points out that girls’ persistent counting provide them with fewer opportunities to practice derived fact strategies and retrieval and that might lead to girls’ poorer accuracy in these strategies. Considering the findings of this study, it would be relevant to investigate the effects of different aspects of instructional practices on sex specific development of strategies in arithmetic in the early years. For example, boys are known to be more willing to take risks in a competitive environment and it could be that teaching promoting a competitive learning environment may be more beneficial for boys, whereas girls might experience a reinforcement of the feedback loop (Bailey et al., 2012).

Conclusion and perspectives
We have shown the existence of considerable specific sex differences in one of the foundational aspects of teaching number in the early years arithmetic, in the very first years of formal Danish schooling. Considering the lack of research on the learning and development of number and arithmetic in the early years of school in Denmark, as well as early sex differences, we find that it is important that these findings are reported. The reasons behind these sex differences, equalling 2–3 year’s, remain to be explicated. No matter the reasons behind these sex differences, their sheer magnitude in this as well as in at least one previous study (Bailey et al., 2012) may suggest that sex differences and their underlying causes deserves more attention than appear to be standard in most studies of arithmetic in early years of school. Although a systematic review of the extent to which the presence and magnitude of sex differences in arithmetic research is beyond the scope of this paper, it seems that sex differences are sometimes not quantified in research papers, which means that sex differences in arithmetic patterns possibly could be underreported. The occurrence of differences in arithmetic patterns between boys and girls may be considered politically sensitive and vulnerable to partisan misinterpretations, but this does not change the fact that they sometimes exist and should be investigated, quantified and explained as any other predictor variable in education research. Knowledge on how individual differences and sociocultural factors interact to produce the resulting sex differences might thus prove useful to inform targeted teaching and educational practice that ‘decrease’ rather than unintentionally enhance sex differences no matter what have caused them.

Lassitude: Reducing energetically expensive movement to make more energy available to the immune system, reducing exposure to additional infections and injuries, deploying strategies that elicit caregiving behavior from social allies

Lassitude: The emotion of being sick. Joshua M. Schrock, J. Josh Snodgrass, Lawrence S. Sugiyama. Evolution and Human Behavior, Volume 41, Issue 1, January 2020, Pages 44-57.

Abstract: Our long co-evolutionary history with infectious agents likely began soon after the rise of the first single-celled organisms. This ongoing evolutionary arms race has generated complex host adaptations, many highly conserved, for resisting infection (e.g., innate and acquired immune systems, infection-sensitive developmental programs, sexual reproduction). A large body of evidence suggests that, in humans, pathogen-avoidance disgust is an emotion that motivates avoidance of cues associated with pathogens, thereby reducing infection. However, the question of whether there is an emotion that coordinates resistance to active infection has received less attention. We propose that lassitude is such an emotion. It is triggered by cues of active infection and coordinates the fight against infection by: (a) reducing energetically expensive movement to make more energy available to the immune system, (b) reducing exposure to additional infections and injuries that would compound the immune system's workload, (c) promoting thermoregulatory behaviors that facilitate immunity, (d) regulating food consumption to be beneficial for the host but detrimental to pathogens, and (e) deploying strategies that elicit caregiving behavior from social allies. Lassitude exhibits the core features of an emotion – it is triggered by cues of an adaptive problem (i.e., infection), generates a characteristic facial expression (e.g., slack facial muscles, drooping eyelids, slightly parted lips), and has distinct qualia (e.g., profound tiredness, reduced appetite, feelings of vulnerability, altered temperature perception, increased pain sensitivity). We outline the information-processing structure of lassitude, review existing evidence, suggest directions for future research, and discuss implications of lassitude for models of human evolution.

5. Lassitude: a new emotion?

Our approach to characterizing lassitude is informed by Tooby and Cosmides' framework: “[the emotions] are the neurocomputational adaptations that have evolved in response to the adaptive problem of matching arrays of mechanism activation to the specific adaptive demands imposed by alternative situations” (Tooby & Cosmides, 2008, p. 117). Lassitude satisfies this definition of an emotion. It is a coordinating system that functions to orchestrate various mechanisms to solve the adaptive problem of fighting infectious disease.
Other theoretical approaches emphasize the distinctive facial expression and qualia of an emotion (Ekman & Oster, 1979; Frijda, 2005). We propose that lassitude has a distinctive facial expression generated by less muscle tension relative to a neutral facial expression (i.e., slack facial muscles). In particular, it consists of a long crown-to-chin length, drooping eyelids, and slightly parted lips. A recent study showed participants pictures of faces of people who had been injected with LPS or with placebo (Axelsson et al., 2018). Participants correctly identified the faces of sick people at a higher rate than chance, even though individuals in the photos were instructed to exhibit a neutral facial expression, which may have resulted in partial masking of the facial expression of lassitude. The faces of sick people were rated as having droopy corners of the mouth, having hanging eyelids, looking more tired, having redder eyes, and having paler, puffier skin. We propose that lassitude also has distinct qualia – profound tiredness, greater relative preference for close social allies, reduced overall appetite but stronger relative preference for particular food items, greater feelings of vulnerability, increased pain sensitivity, greater susceptibility to nausea, and altered perceptions of ambient temperature. Not all of these qualia are present in all cases of infection – the presence of each component depends on context-sensitive regulation of the underlying motivational system.
Panksepp's account of basic emotions emphasizes universality across species of mammals and conserved neural circuitry (Panksepp, 1982). Lassitude involves specific immune and neural signaling pathways that have been mapped with increasing thoroughness in animal models (McCusker & Kelley, 2013). Lassitude-like regulatory states exist not only in mammals but also birds (Owen-Ashley & Wingfield, 2007), amphibians (Llewellyn et al., 2011), and possibly even fish (Kirsten, Fior, Kreutz, & Barcellos, 2018).
Based on the criteria discussed here, lassitude is an emotion, albeit one that has gone unrecognized. It is worth noting that there are at least two ways in which our account of lassitude is not novel. First, Tooby and Cosmides hypothesized that malaise during infection might be an evolved emotion but did not elaborate (Tooby & Cosmides, 2008). Second, scholars who study sickness behavior, focusing mostly on non-humans, have proposed that many infection-induced behavioral changes are evolutionarily adaptive (Adelman & Martin, 2009; Hart, 1990). However, the sickness behavior literature largely focuses on the description of infection-related behavior and its physiological mechanisms. It has largely neglected to characterize the evolutionary background, information-processing structure, and functional logic of the regulatory system that generates sickness behavior.

6. Directions for future research

6.1. Social support and immunity

Humans provide care to social allies during illness and injury (see section 2.2.5). This is an important buffer against the opportunity costs of reducing movement when sick. A compelling hypothesis to explain the placebo effect is that one function of visible illness symptoms is to elicit care from others (Steinkopf, 2015). When others provide care, the signaling function of the symptoms is fulfilled and the symptoms become less severe (ibid). We predict that cues of social support (or a lack thereof) are also key inputs for modulating the regulation of lassitude during infection. Infected individuals who are socially isolated may be unable to afford to devote as much energy to fighting infection, and may therefore experience longer-lasting infections and higher mortality risks. In support of this hypothesis, there is evidence to suggest that those who are socially isolated tend to suffer from poorer health (Cacioppo & Cacioppo, 2014).

6.2. Lassitude in healthcare settings

We hypothesize that cues of infection increase the relative preference for contact with social allies. Furthermore, we propose that sick individuals boost signals of vulnerability when in the presence of social allies (in order to elicit care) and mask signals of vulnerability in front of strangers and antagonists (in order to reduce the risk of social and physical danger during the vulnerable state of sickness). This suggests that the degree to which a patient sees a healthcare provider as a social ally may have a major influence on a patient's decision to pursue care, and ability to elicit it.
Patients who do not see providers as social allies may be less likely to seek healthcare, and when they do, may have greater difficulty eliciting useful care, due to the fact that they are (perhaps inadvertently) masking signals of vulnerability. This may help explain why many patients highly value good “bedside manner” in healthcare providers (Thompson & Anderson, 1982).

6.3. Lassitude and chronic disease

There is evidence to suggest that chronic diseases (e.g., heart disease, diabetes, chronic obstructive pulmonary disorder) may activate a response that resembles a chronic version of lassitude (Swain, 2000). This may be due, in part, to the fact that chronic somatic damage activates some of the same pro-inflammatory immune pathways that trigger lassitude during infection (Del Giudice & Gangestad, 2018; McCusker & Kelley, 2013). This poses a problem because one of most effective interventions for preventing and treating chronic disease is to engage in healthy levels of physical activity (Warburton, Nicol, & Bredin, 2006). The motivational state of lassitude directly opposes this goal. Thus, even sub-clinical levels of chronic morbidity may trigger a vicious, self-reinforcing cycle in which greater chronic morbidity leads to greater lassitude, and greater lassitude leads to even greater chronic morbidity. This cycle may help explain why chronic disease epidemics emerge when populations transition to economic sectors with a greater proportion of sedentary occupations (Omran, 2005).

6.4. Lassitude in relation to time, reward, and risk preferences

We hypothesize that lassitude modifies the cost-benefit structure of a wide range of decisions. Individuals in a state of lassitude place a lower value on some types of rewards (e.g., food, sex). Higher levels of lassitude may therefore generate a greater willingness to delay some kinds of payoffs in temporal discounting scenarios (Green, Myerson, & Mcfadden, 1997). We also propose that individuals in a state of lassitude place a greater value on avoiding social and physical risks. Thus, lassitude may induce greater risk aversion when the risks are social or physical. On the other hand, lassitude may induce less aversion to the risk of losing a potential payoff that has lower value during lassitude (e.g., food, sex). Researchers who study time-, reward-, and risk-related decision-making should therefore consider incorporating lassitude into their studies and theoretical models.

6.5. Approach-avoidance conflict

The fact that humans systematically help social allies during illness suggests that we have cognitive mechanisms for detecting signs of illness in others and deciding how to respond. The occurence of illness in a social conspecific poses a potential motivational conflict. On one hand, helping the sick individual may induce the target of aid to reciprocate in the future, when the roles are reversed (Gurven et al., 2000; Sugiyama, 2004; Sugiyama & Chacon, 2000). Furthermore, helping sick individuals provides a costly signal of the helper's quality as a social ally (Steinkopf, 2015). On the other hand, the effort required for providing aid is costly, and providing aid to a sick person may increase the helper's risk of getting sick (Tybur et al., 2012). Thus, navigating the motivational conflict between approaching a sick individual (to help them) and avoiding them (to reduce infection risk) is an important adaptive problem for humans. Variables that influence the decision to help or avoid a sick person may include the relationship/kinship of the sick person to the helper, the sick person's reputation as a reciprocator, the helper's vulnerability to illness, and the social audience that would be aware of the helping behavior.

Sexting is a common behavior among emerging adults (18-29 y.o.); the prevalence of non-consensual forwarding of sexts was also frequent in emerging adults (15.0%)

The Prevalence of Sexting Behaviors Among Emerging Adults: A Meta-Analysis. Camille Mori, Jessica E. Cooke, Jeff R. Temple, Anh Ly, Yu Lu, Nina Anderson, Christina Rash & Sheri Madigan. Archives of Sexual Behavior, Feb 18 2020.

Abstract: Sexting is the sharing of sexually explicit images, videos, and/or messages via electronic devices. Prevalence estimates of sexting have varied substantially, potentially due to broad age ranges being examined. The current study sought to synthesize relevant findings examining the prevalence of consensual and non-consensual sexting in a specific developmental period, emerging adulthood (≥ 18–< 29), to try to explain discrepancies in the literature. Searches were conducted in electronic databases for articles published up to April 2018. Relevant data from 50 studies with 18,122 emerging adults were extracted. The prevalence of sexting behaviors were: sending 38.3% (k = 41; CI 32.0–44.6), receiving 41.5% (k = 19; CI 31.9–51.2), and reciprocal sexting 47.7% (k = 16; CI 37.6–57.8). Thus, sexting is a common behavior among emerging adults. The prevalence of non-consensual forwarding of sexts was also frequent in emerging adults at 15.0% (k = 7; CI 6.9–23.2). Educational awareness initiatives on digital citizenship and psychological consequences of the non-consensual forwarding of sexts should be targeted to youth and emerging adults with the hopes of mitigating this potentially damaging and illegal behavior.

Proust had the intuition that olfactory stimuli are very powerful to recall old episodic memories; olfactory function & memory rapidly decline with age; he didn't know that in addition to remembering the past, memory is used to predict the future

Did Proust predict the existence of episodic memory? Michel Baudry. Neurobiology of Learning and Memory, February 19 2020, 107191.

•    Proust had the intuition that olfactory stimuli are very powerful to recall old episodic memories.
•    Olfactory function and memory rapidly decline with age.
•    The hippocampus, in addition to place cells, has odor cells.
•    In addition to remembering the past, memory is used to predict the future.
•    Proust was one of several writers who predicted the existence of episodic memory.

Abstract: Cognitive psychologists have often discussed the idea that when Proust used in his books the concept of involuntary memories, which could be retrieved by an odor or a taste, he was in fact predating the notion of modern episodic memory. Since the publication of his famous “In Search of Lost Time”, considerable progress has been made on our understanding of various types of memory and of the mechanisms involved in different brain circuits and synapses responsible for their long-term storage. This review will focus on the role of hippocampus in episodic memory, including its role in encoding time and various elements of episodes, in particular olfactory information. Our conclusion is that Proust did indeed predict the existence of episodic memory, although he did not realize that, in addition to remembering things past, memory is also used to predict the future.

Citations have become the dominant way to evaluate scientific contributions & scientists; this way to measure productivity shifted scientist rewards & behavior toward incremental science & away from exploratory projects that are more likely to fail

Stagnation and Scientific Incentives. Jay Bhattacharya, Mikko Packalen. NBER Working Paper No. 26752, February 2020. DOI 10.3386/w26752

Abstract: New ideas no longer fuel economic growth the way they once did. A popular explanation for stagnation is that good ideas are harder to find, rendering slowdown inevitable. We present a simple model of the lifecycle of scientific ideas that points to changes in scientist incentives as the cause of scientific stagnation. Over the last five decades, citations have become the dominant way to evaluate scientific contributions and scientists. This emphasis on citations in the measurement of scientific productivity shifted scientist rewards and behavior on the margin toward incremental science and away from exploratory projects that are more likely to fail, but which are the fuel for future breakthroughs. As attention given to new ideas decreased, science stagnated. We also explore ways to broaden how scientific productivity is measured and rewarded, involving both academic search engines such as Google Scholar measuring which contributions explore newer ideas and university administrators and funding agencies utilizing these new metrics in research evaluation. We demonstrate empirically that measures of novelty are correlated with but distinct from measures of scientific impact, which suggests that if also novelty metrics were utilized in scientist evaluation, scientists might pursue more innovative, riskier, projects.


Trypophobia (disgust evoked by clusters of holes or round objects) might be a modern emotion and hence, urbanization possibly plays key roles in it; & older people in less urban area did not experience as much trypophobia

Zhu, Siqi, Kyoshiro Sasaki, Yue Jiang, Kun Qian, and Yuki Yamada. 2019. “Trypophobia as an Urbanized Emotion: Comparative Research in Ethnic Minority Regions of China.” PsyArXiv. August 30. doi:10.31234/

Abstract: Trypophobia is a strong emotion of disgust evoked by clusters of holes or round objects (e.g., lotus seed pod). It has become increasingly popular and been studied since 2010s, mainly in the West and Japan. Considering this, trypophobia might be a modern emotion and hence, urbanization possibly plays key roles in trypophobia. To address this issue, we compared the degree of trypophobia between urban and less urban people in China. In an experiment, we asked participants about their degree of discomfort from trypophobic images. The results showed that trypophobia occurred in both groups, although the effect size was larger in urban than less urban people. Moreover, post-experimental interviews and post-hoc analyses revealed that older people in less urban area did not experience as much trypophobia. Our findings suggest that trypophobia links to urbanization and age-related properties.