Wednesday, December 5, 2018

Sex differences in own and other body perception: Other body images, particularly of the opposite sex, may be of greater salience for men, whereas images of own bodies may be more salient for women

Sex differences in own and other body perception. Sarah M. Burke et al. Human Brain Mapping,

Abstract: Own body perception, and differentiating and comparing one's body to another person's body, are common cognitive functions that have relevance for self‐identity and social interactions. In several psychiatric conditions, including anorexia nervosa, body dysmorphic disorder, gender dysphoria, and autism spectrum disorder, self and own body perception, as well as aspects of social communication are disturbed. Despite most of these conditions having skewed prevalence sex ratios, little is known about whether the neural basis of own body perception differs between the sexes. We addressed this question by investigating brain activation using functional magnetic resonance imaging during a Body Perception task in 15 male and 15 female healthy participants. Participants viewed their own body, bodies of same‐sex, or opposite‐sex other people, and rated the degree that they appeared like themselves. We found that men and women did not differ in the pattern of brain activation during own body perception compared to a scrambled control image. However, when viewing images of other bodies of same‐sex or opposite‐sex, men showed significantly stronger activations in attention‐related and reward‐related brain regions, whereas women engaged stronger activations in striatal, medial‐prefrontal, and insular cortices, when viewing the own body compared to other images of the opposite sex. It is possible that other body images, particularly of the opposite sex, may be of greater salience for men, whereas images of own bodies may be more salient for women. These observations provide tentative neurobiological correlates to why women may be more vulnerable than men to conditions involving own body perception.

Psychological hibernation in Antarctica

Psychological hibernation in Antarctica. Gro M Sandal, Fons Van De Vijver, Nathan Smith. Frontiers in Psychology, 2018 Nov 19. DOI: 10.3389/fpsyg.2018.02235

Abstract: Human activity in Antarctica has increased sharply in recent years. In particular during the winter months, people are exposed to long periods of isolation and confinement and an extreme physical environment that poses risks to health, well-being and performance. The aim of the present study was to gain a better understanding of processes contributing to psychological resilience in this context. Specifically, the study examined how the use of coping strategies changed over time, and the extent to which changes coincided with alterations in mood and sleep. Two crews (N=27) spending approximately 10 months at the Concordia station completed the Utrecht Coping List, the Positive and Negative Affect Schedule (PANAS), and a structured sleep diary at regular intervals (x 9). The results showed that several variables reached a minimum value during the midwinter period, which corresponded to the third quarter of the expedition. The effect was particularly noticeable for coping strategies (i.e., active problem solving, palliative reactions, avoidance, and comforting cognitions). The pattern of results could indicate that participants during Antarctic over-wintering enter a state of psychological hibernation as a stress coping mechanism.

The findings from this study suggest that coping strategies, sleep quality, and PA were influenced by the environmental conditions to a smaller or larger degree during midwinter. Quadratic time-based models demonstrated the greatest effect sizes, suggesting that when the conditions are harshest, resources are more depleted and participants were less involved in any form of coping and reported less PA. Also subjective sleep quality showed a negative trend over time, a result consistent with other research (Bhargava et al., 2000; Pattyn et al., 2018) although at the end of the stay the average score did increase slightly. While chronic hypoxia might lead to deterioration in sleep quality in high altitude (Collet et al., 2015), the effect of hypoxia on adaptation among residents on Concordia has been shown to persist over time (Porcelli et al., 2018). Thus, we argue that hypoxia cannot explain seasonal variations in sleep quality observed in this study. The reduction in sleep quality and PA is consistent with the “midwinter syndrome” observed by other researchers (Bhargava et al., 2000; Palinkas and Suedfeld, 2008). It is noticeable that reports of NA remained low over time and did not show the expected change during midwinter. One possible explanation is that participants were reluctant to report distress.

Perhaps the most striking result from this study was the reduction in all of observed coping strategies during the midwinter period. This pattern contradicts the idea that emotional strategies and avoidance take over from more active strategies in situations involving chronic stressors. Our findings may reflect that participants became more indifferent or emotionally flat during the winter months. This interpretation is consistent with early research which noted the occurrence of a mild psychological fugue state known as the Antarctic stare, around the third quarter of the stay (Barabasz et al., 1983). The phenomenon state is characterized by an altered state of consciousness or pronounced absentmindedness, “drifting,” wandering off attention, and deterioration in situational awareness. We believe that this reaction is not unique to people overwintering in Antarctica. For example, during a 520 days confinement study (MARS500) crew members reported reduced need for stimulation around the third quarter (Sandal and Bye, 2015). Interactions between crew members declined, and one crew member showed indications of dissociation. The state of seeking reduced stimulation, and emotional flatness bears resemblance to what could be called “psychological hibernation.” A state of psychological hibernation may be beneficial for coping with the harshness of prolonged exposure to stress in extreme environments. The ability to “switch off” mentally has been associated with positive outcomes in the work stress literature (Sonnentag and Bayer, 2005). However, psychological detachment has also been described as a symptom of burnout after prolonged exposure to stress at work (Maslach and Leiter, 2016). Whilst psychological hibernation could be an adaptive response to the extreme conditions, especially if it disappears when conditions become less extreme (as evidenced by the increase in coping strategy use reported in the present study), understanding the nature of this phenomenon should be an avenue for future research. Further research is also needed to determine the extent to which this state might be associated with decrement in cognitive function and the ability to react to acute, safety-critical situations. So far studies on cognitive performance investigations on Antarctica have been controversial. While no detectable cognitive deterioration was found in a study of a crew overwintering on Concordia (Barkaszi et al., 2016), other researchers have shown that residence in Antarctica had a detrimental effect on cognition (Reed et al., 2001).

In social risk, the costs, benefits, & uncertainty of an action depend on the behavior of another individual; humans & chimpanzees overvalue the costs of a socially risky decision when compared with that of purely economic risk

Chimpanzees (Pan troglodytes) Are More Averse to Social Than Nonsocial Risk. Sarah E. Calcutt et al. Psychological Science,

Abstract: Social risk is a domain of risk in which the costs, benefits, and uncertainty of an action depend on the behavior of another individual. Humans overvalue the costs of a socially risky decision when compared with that of purely economic risk. Here, we played a trust game with 8 female captive chimpanzees (Pan troglodytes) to determine whether this bias exists in one of our closest living relatives. A correlation between an individual’s social- and nonsocial-risk attitudes indicated stable individual variation, yet the chimpanzees were more averse to social than nonsocial risk. This indicates differences between social and economic decision making and emotional factors in social risk taking. In another experiment using the same paradigm, subjects played with several partners with whom they had varying relationships. Preexisting relationships did not impact the subjects’ choices. Instead, the apes used a tit-for-tat strategy and were influenced by the outcome of early interactions with a partner.

Keywords: trust, chimpanzee, risk, relationships, tit-for-tat