The expression of c-Fos and colocalisation of c-Fos and glucocorticoid receptors in brain structures of low and high anxiety rats subjected to extinction trials and re-learning of a conditioned fear response

We designed an animal model to examine the mechanisms of differences in individual responses to aversive stimuli. We used the rat freezing response in the context fear test as a discriminating variable: low responders (LR) were defined as rats with a duration of freezing response one standard error or more below the mean value, and high responders (HR) were defined as rats with a duration of freezing response one standard error or more above the mean value. We sought to determine the colocalisation of c-Fos and glucocorticoid receptors-immunoreactivity (GR-ir) in HR and LR rats subjected to conditioned fear training, two extinction sessions and re-learning of a conditioned fear. We found that HR animals showed a marked decrease in conditioned fear in the course of two extinction sessions (16 days) in comparison with the control and LR groups. The LR group exhibited higher activity in the cortical M2 and prelimbic areas (c-Fos) and had an increased number of cells co-expressing c-Fos and GR-ir in the M2 and medial orbital cortex after re-learning a contextual fear. HR rats showed increased expression of c-Fos, GR-ir and c-Fos/GR-ir colocalised neurons in the basolateral amygdala and enhanced c-Fos and GR-ir in the dentate gyrus (DG) in comparison with LR animals. Our data indicate that recovery of a context-related behaviour upon re-learning of contextual fear is accompanied in HR animals by a selective increase in c-Fos expression and GRs-ir in the DG area of the hippocampus.     

Trolley Dilemma in Papua. Yali horticulturalists refuse to pull the lever

Psychonomic Bulletin & Review - Although many studies show cultural or ecological variability in moral judgments, cross-cultural responses to the trolley problem (kill one person to save five...     

Does Personality Smell? Accuracy of Personality Assessments Based on Body Odour

People are able to assess some personality traits of others based on videotaped behaviour, short interaction or a photograph. In our study, we investigated the relationship between body odour and the Big Five personality dimensions and dominance. Sixty odour samples were assessed by 20 raters each. The main finding of the presented study is that for a few personality traits, the correlation between self‐assessed personality of odour donors and judgments based on their body odour was above chance level. The correlations were strongest for extraversion (.36), neuroticism (.34) and dominance (.29). Further analyses showed that self–other agreement in assessments of neuroticism slightly differed between sexes and that the ratings of dominance were particularly accurate for assessments of the opposite sex. Copyright © 2011 John Wiley & Sons, Ltd.     

The 9th annual INDUS-EM 2013 Emergency Medicine Summit, “Principles,Practices, and Patients,” a level one international meeting,Kerala University of Health Sciences and Jubilee Mission Medical College and Research Institute,Thrissur, Kerala,India, October 23–27, 2013

INDUS-EM is India’s only level one conference imparting and exchanging quality knowledge in acute care. Specifically, in general and specialized emergency care and training in trauma, burns, cardiac, stroke, environmental and disaster medicine. It provides a series of exchanges regarding academic development and implementation of training tools related to developing future academic faculty and residents in Emergency Medicine in India. The INDUS-EM leadership and board of directors invited scholars from multiple institutions to participate in this advanced educational symposium that was held in Thrissur, Kerala in October 2013.     

Evidence against a constant-difference effect in concurrent-chains schedules

Savastano and Fantino (1996) reported that in concurrent-chains schedules, initial-link choice proportions remained constant as terminal-link durations increased as long as the subtractive difference between the two terminal-link schedules remained constant. Two experiments with pigeons were conducted to examine this constant-difference effect. Both experiments used equal variable-interval schedules as initial links. The terminal links were fixed delays to reinforcement in Experiment 1 and variable delays to reinforcement in Experiment 2. The durations of the terminal links were varied across conditions, but the difference between pairs of terminal links was always 10 s. In both experiments, preference for the shorter terminal link became less extreme as terminal-link durations increased, so a constant-difference effect was not found. It is argued, however, that this choice situation does not provide clear evidence for or against delay-reduction theory versus other theories of choice.     

Mixed matters: fluency impacts trust ratings when faces range on valence but not on motivational implications

Facial features that resemble emotional expressions influence key social evaluations, including trust. Here, we present four experiments testing how the impact of such expressive features is qualified by their processing difficulty. We show that faces with mixed expressive features are relatively devalued, and faces with pure expressive features are relatively valued. This is especially true when participants first engage in a categorisation task that makes processing of mixed expressions difficult and pure expressions easy. Critically, we also demonstrate that the impact of categorisation fluency depends on the specific nature of the expressive features. When faces vary on valence (i.e. sad to happy), trust judgments increase with their positivity, but also depend on fluency. When faces vary on social motivation (i.e. angry to sad), trust judgments increase with their approachability, but remain impervious to disfluency. This suggests that people intelligently use fluency to make judgments on valence-relevant judgment dimensions – but not when faces can be judged using other relevant criteria, such as motivation. Overall, the findings highlight that key social impressions (like trust) are flexibly constructed from inputs related to stimulus features and processing experience.