Monday, October 22, 2018

Ventral pallidum encodes relative reward value earlier and more robustly than nucleus accumbens, challenging the existing model of information flow in the ventral basal ganglia

Ventral pallidum encodes relative reward value earlier and more robustly than nucleus accumbens. David Ottenheimer, Jocelyn M. Richard & Patricia H. Janak. Nature Communications, volume 9, Article number: 4350 (2018). https://www.nature.com/articles/s41467-018-06849-z

Abstract: The ventral striatopallidal system, a basal ganglia network thought to convert limbic information into behavioral action, includes the nucleus accumbens (NAc) and the ventral pallidum (VP), typically described as a major output of NAc. Here, to investigate how reward-related information is transformed across this circuit, we measure the activity of neurons in NAc and VP when rats receive two highly palatable but differentially preferred rewards, allowing us to track the reward-specific information contained within the neural activity of each region. In VP, we find a prominent preference-related signal that flexibly reports the relative value of reward outcomes across multiple conditions. This reward-specific firing in VP is present in a greater proportion of the population and arises sooner following reward delivery than in NAc. Our findings establish VP as a preeminent value signaler and challenge the existing model of information flow in the ventral basal ganglia.

Personality-trait profiles were predicted reliably from a subset of the body-shape features; extraversion & conscientiousness were predicted with the highest consensus, followed by openness traits

First Impressions of Personality Traits From Body Shapes. Ying Hu, Connor J. Parde, Matthew Q. Hill, Naureen Mahmood, Alice J. O’Toole. Psychological Science, https://doi.org/10.1177/0956797618799300

Abstract: People infer the personalities of others from their facial appearance. Whether they do so from body shapes is less studied. We explored personality inferences made from body shapes. Participants rated personality traits for male and female bodies generated with a three-dimensional body model. Multivariate spaces created from these ratings indicated that people evaluate bodies on valence and agency in ways that directly contrast positive and negative traits from the Big Five domains. Body-trait stereotypes based on the trait ratings revealed a myriad of diverse body shapes that typify individual traits. Personality-trait profiles were predicted reliably from a subset of the body-shape features used to specify the three-dimensional bodies. Body features related to extraversion and conscientiousness were predicted with the highest consensus, followed by openness traits. This study provides the first comprehensive look at the range, diversity, and reliability of personality inferences that people make from body shapes.

Keywords: Big Five personality domains, first impressions, human body perception, correspondence analysis, open data

Effects of paracetamol on empathy-like behavior in Sprague Dawley rats: It reduced empathy-like behavior, with rats helping less drowning conspecifics

Acetaminophen (paracetamol) affects empathy-like behavior in rats: Dose-response relationship. Sevim Kandis et al. Pharmacology Biochemistry and Behavior, https://doi.org/10.1016/j.pbb.2018.10.004

Highlights
•    Single high dose and repeated low and high doses of acetaminophen lead to a reduction of oxytocin and vasopressin release in the prefrontal cortex and amygdalae; in addition to reduce empathy-like behavior.
•    Oxytocin and vasopressin reduction in the prefrontal cortex and amygdalae is negatively correlated with empathy-like behavior.

Abstract: Empathy is the ability to recognize, process and respond to another's emotional state and empathic functions have been linked with a multitude of cognitive and affective processes. Impaired empathy has been linked to aggression and criminal behavior in society. Acetaminophen (paracetamol) is among the most common nonprescription (over the counter) analgesics in the world and has been already linked to reducing empathic behavior in humans. The aim of this study is to investigate the effects of acetaminophen on empathy-like behavior in Sprague Dawley rats, and we further explored the underlying mechanisms by analyzing empathy related neurohormones, e.g. oxytocin and vasopressin, in association with acetaminophen exposure in rats. Empathic behavior was assessed 30 min following acetaminophen administration (100, 200, and 400 mg/kg). The impact of single and repeated acetaminophen administrations on empathy-like behavior and anxiety level were evaluated separately. Empathy-like behavior was reduced with a single high dose of acetaminophen. Subsequent low dose administration of acetaminophen also reduced empathy-like behavior. In this study we also showed that acetaminophen decreased oxytocin and vasopressin levels in the prefrontal cortex and amygdalae. We found a negative correlation between delay in door opening time and measured prefrontal cortex oxytocin levels; we adjudged the latency in door opening time as enhanced empathic behavior which seemingly suggested the existence of a mechanism between empathy-like behavior and the prefrontal oxytocin. We observed that both a single high dose or repeated low dose administrations of acetaminophen reduced empathy-like behavior in correlation with a decrease in oxytocin and vasopressin levels in the prefrontal cortex and amygdala. Further research is needed to investigate the role of acetaminophen on the other empathic brain pathways.

Cichocka et al. (2016) report evidence that conservatism (specifically social conservatism) is associated with noun preference. This study replicates the finding.

Crawford, Jarret. 2018. “Examining the Effects of Political Orientation on Noun Preference: A Replication of Cichocka Et Al. (2016).” PsyArXiv. October 22. doi:10.31234/osf.io/m5paz

Abstract: In three studies, Cichocka et al. (2016) report evidence that conservatism (specifically social conservatism) is associated with noun preference, and that this relationship is mediated by needs for structure and order. We conducted a conceptual replication of Study 1 and found that whereas we could replicate the relationship between social conservatism and noun preference, personal need for structure did not mediate this relationship, as PNS was not associated with noun preference. Our observed effect size for the relationship between social conservatism and noun preference is quite similar to those reported in Cichocka et al. (2016). However, at least based on the present replication, the mechanism behind this relationship is unclear.

Our results suggest that childhood trauma in humans is associated with changes in cortical fields that are implicated in the perception or processing of the abuse

Psychobiological Consequences of Child Maltreatment. Christine Heim. The Biology of Early Life Stress. In  Child Maltreatment Solutions Network book series (CMSN), pp 15-30. https://link.springer.com/chapter/10.1007/978-3-319-72589-5_2

Abstract: Adversity in early life, such as childhood abuse, neglect, and loss, is a well-established major risk factor for developing a range of psychiatric and medical disorders later in life. Biological embedding of maltreatment during development is thought to underlie this long-term increased risk. Our results suggest that childhood trauma in humans is associated with sensitization of the stress response, glucocorticoid resistance, decreased oxytocin activity, inflammation, reduced hippocampal volume, and changes in cortical fields that are implicated in the perception or processing of the abuse. The consequences of childhood trauma are moderated by genetic factors and mediated by epigenetic changes in genes relevant for stress regulation. Understanding longitudinal trajectories of biological embedding, and their moderation by gene–environment interaction, is critical to enable us to design novel interventions that directly reverse these processes and to derive biomarkers that identify children who are at risk to develop disorders or are susceptible to a specific intervention.

Keywords: HPA axis Amygdala Biological embedding Child maltreatment Hippocampus Stress response

Cross-Culturally, Younger Escorts Advertise Higher Charges Online than Older Escorts for Sexual Services

Younger Escorts Advertise Higher Charges Online than Older Escorts for Sexual Services Cross-Culturally. Michael J. Dunn. Evolutionary Psychological Science, September 2018, Volume 4, Issue 3, pp 331–339, https://link.springer.com/article/10.1007/s40806-018-0142-z

Abstract: As men have universally expressed attraction to younger women, awareness of this proclivity in men by women should be maximally reflected in terms of mate value in younger compared to older women. Prostitution has been recorded across all cultures and historical epochs, and one way in which mate value in women can be explored is by obtaining data from online escort advertising sites. The current study accessed an online escort site called adultwork.com to compare advertised fees between escorts at various ages and age ranges in five different cultures (UK, Ireland, Australia, the USA and Europe) offering either incall or outcall sexual services. With the exception of Irish escorts advertising for an outcall service, differences were found in all countries sampled with younger escorts charging significantly higher fees than older escorts. The current findings are another example of how by accessing real-world online data we can successfully test hypotheses relating to sexual behaviour from an evolutionary psychological perspective.

Keywords: Mate value Age comparisons Female escorts Reproductive value Online advertisements Evolutionary psychological perspective

Century of Decline in General Intelligence? Testing Predictions from the Genetic Selection and Neurotoxin Hypotheses authors found that this last did not significantly predict variance of g factor

What Caused over a Century of Decline in General Intelligence? Testing Predictions from the Genetic Selection and Neurotoxin Hypotheses. Michael A. Woodley of Menie et al. Evolutionary Psychological Science, September 2018, Volume 4, Issue 3, pp 272–284. https://link.springer.com/article/10.1007/s40806-017-0131-7

Abstract: Several converging lines of evidence indicate that general intelligence (g) has declined in Western populations. The causes of these declines are debated. Here, two hypotheses are tested: (1) selection acting against genetic variants that promote g causes the decline and (2) the presence of neurotoxic pollution in the environment causes the decline. A linear mixed model was devised to test (1) and (2), in which the secular decline in a “heritable g” (g.h) chronometric factor (comprised of convergent indicators of simple reaction time, working memory, utilization frequencies of high difficulty and also social-intelligence-indicating vocabulary items and per capita macro-innovation rates) was predicted using a neurotoxin chronometric factor (comprised of convergent secular trends among measures of lead, mercury and dioxin + furan pollution, in addition to alcohol consumption) and a polygenic score chronometric factor (comprised of polygenic score means for genetic variants predictive of g, sourced from US and Icelandic age-stratified cohorts). Bivariate correlations revealed that (other than time) only the polygenic score factor was significantly associated with declining g.h (r = .393, p < .05 vs. .033, ns for the neurotoxin factor). Using a hierarchical linear mixed model approach incorporating 25 year lags between the predictors and g.h, time period, operationalized categorically as fifths of a century, accounted for the majority of the variance in the decline in g.h (partial η2 = .584, p < .05). Net of time period and neurotoxins, changing levels of polygenic scores also significantly predicted variance in the decline in g.h (partial η2 = .253, p < .05); however, changing levels of neurotoxins did not significantly predict variance in g.h net of time (partial η2 = .027 ns). Within-period analysis indicates that the independent significant positive effect of the polygenic score factor on g.h was restricted to the third fifth of a century period (β = .202, p < .05).

Keywords: Directional selection Dysgenics General intelligence Neurotoxins Polygenic scores

Studies confirmed the existence of a social norm that one cannot simultaneously support two competing groups or teams

You Can’t Root for Both Teams!: Convergent Evidence for the Unidirectionality of Group Loyalty. Daniel J. Kruger et al. Evolutionary Psychological Science, https://link.springer.com/article/10.1007/s40806-018-0178-0

Abstract: Four studies tested the existence of a social norm that one cannot simultaneously support two competing groups or teams. Our evolved coalitional psychology should be sensitive to individuals expressing mixed loyalties between rivals, as they represent substantial threats for defection. Study 1 manipulated confederate attire and demonstrated that public displays of mixed loyalty provoked more attention and reactions than displays of consistent loyalty (n = 1327). Informants (n = 31) in the same population interviewed for study 2 agreed with the norm and cited the norm violation as the cause of reactions. Study 3 provided a more systematic and comprehensive assessment of affective and cognitive reactions to mixed and matching loyalty displays with an on-line survey of participants (n = 325) in the respective states of the rival universities. Study 4 examined naturalistic reactions (n = 318) to social media advertisements suggesting mixed loyalty to the two rival teams featured in the first three studies. These diverse methodologies provided convergent confirmatory evidence for the proposed social norm.

Keywords: Teams Intergroup perception Evolutionary psychology Loyalty Observational methods

Examining Cross‐Cultural Differences in Academic Faking in 41 Nations: Faking was positively related to the cultural dimensions of gender egalitarianism, humane orientation, and in‐group collectivism

Examining Cross‐Cultural Differences in Academic Faking in 41 Nations. Clemens B. Fell, Cornelius J. König. Applied Psychology, https://doi.org/10.1111/apps.12178

Abstract: This study examines cross‐cultural differences in students’ academic faking (indicated by claiming to have impossible knowledge about mathematical concepts) by relating data from the Programme for International Student Assessment (PISA) to the comprehensive cultural framework of the Global Leadership and Organizational Behavior Effectiveness (GLOBE) project. Data of N = 233,428 students from 41 countries showed a substantial amount of variance in academic faking between cultures. Students’ academic faking was positively related to the cultural dimensions of gender egalitarianism, humane orientation, and in‐group collectivism. Additionally, the similarity between female and male students’ academic faking was slightly greater in more gender‐egalitarian cultures than in less gender‐egalitarian cultures. Thus, educational stakeholders (e.g., teachers, principals, and policy makers) should be made aware of cross‐cultural differences in academic faking because faking gives fakers an unfair advantage.