Is behavioral pro-sociality game-specific? Pro-social preference and expectations of pro-sociality

We observed the behaviors of the same people across five games – two prisoner’s dilemma games, a trust game (in which the subject took on the role of both truster and trustee), a dictator game, and a faith game – any pair of which was separated by an interval of several months to reduce potential carry-over effects, and found strong consistency in behaviors among these games. We also found consistency between the expectations of other players’ behaviors and the player’s own behavior across games. We further found that the consistent behavioral pro-sociality observed across different games was related to the general measures of pro-social value orientation and perceiving the game situations. These findings suggest that individual and cultural differences in game behaviors can reflect both the ways in which people perceive game situations and their general social preferences.     

Blood pressure and heart rate responses to an intrusion on personal space

Abstract: Yaezawa and Yoshida's (1981 ) findings on the effects of an intrusion on personal space were reinvestigated. Thirty-five female students were confronted with the approach of a male stranger, and blood pressure (BP) and heart rate (HR) were monitored. Throughout the model's approach, HR showed a significant triphasic change (an initial decrease, a subsequent increase, and then a secondary decrease), whereas subjective feelings of anxiety and tension showed significant, gradual increases. These trends were similar to those of Yaezawa and Yoshida's . Nonetheless, their explanation that the triphasic change in HR reflected once hightened and then relieved tension, which was incongruent with the subjective ratings, seemed questionable. As the BP elevated to a moderate degree in spite of the modest HR changes, total peripheral resistance must have been increasing during the model's approach. Blood pressure elevations via this sort of hemodynamic pressor mechanisms have often been reported when a person can only tolerate passively during exposure to stress. This seems to be the case in an intrusion on personal space.     

A preliminary study of the comfort of paced respiration

In order to obtain basal information about what type of externally paced respiration is comfortable, 25 male and 25 female undergraduate students were asked to practice self‐paced respiration. After a 1‐min rehearsal following instructions on comfortable self‐paced respiration, subjects carried out 2 min of self‐paced respiration and rated their level of comfort on a scale of 1–5. This was repeated (up to a maximum of seven times) until the subject recorded a high rating. Results indicated that self‐paced respiration was most comfortable, irrespective of sex, when a respiratory pattern was attained of half the respiratory rate and nearly twice the tidal volume of the trainee's resting condition. Although respiratory sinus arrhythmia and heart rate were indicative of a decrease in cardiac vagal activity and end‐tidal PCO₂ was suggestive of a reduction in anxiety, these effects were small. The results have implications for the utilization of externally paced respiration.     

Long-lasting effects of inescapable-predator stress on brain tryptophan metabolism and the behavior of juvenile mice

The kynurenine (KYN) pathway, which is initiated by indoleamine 2,3-dioxygenase, is the main tryptophan (TRP) metabolic pathway. It shares TRP with the serotonin (5-HT) pathway. We investigated the influence of inescapable-predator (rat) stress on behavior and brain TRP metabolism in mice. Male ICR mice (4W) were exposed to 20-min inescapable-predator stress. Behavior on an elevated plus-maze, and TRP, KYN, and 5-HT levels in the prefrontal cortex, hippocampus, amygdala, and dorsal raphe nuclei were measured 1 and 4 weeks after stress exposure. Predator stress increased the number of open-arm entries (NOA) 4 weeks after stress exposure without altering the number of closed-arm entries (NCA). Thus, the open/closed-arm entry ratio (NOA/NCA) increased after stress exposure. Predator stress increased KYN levels in the prefrontal cortex (until 4 weeks after stress exposure) and dorsal raphe nuclei (for 1 week after stress exposure), decreased 5-HT levels in all brain regions (until 4 weeks after stress exposure). Thus, predator stress increased the KYN/5-HT ratio in all regions, in particular in the prefrontal cortex and hippocampus until 4 weeks after stress exposure. Predator stress shifted the balance between the KYN and 5-HT pathways to the KYN pathway, and induced behavioral disinhibition.     

Intertask consistency of blood pressure responses to laboratory stressors may increase with prolonged exposure

In this study, one of the predictions of the reactivity hypothesis was investigated: the intertask consistency of blood pressure (BP) responses. Twelve young male subjects underwent cold-pressor (14°C) and digit-scan (counting even numbers) tests in randomized order. Cardiovascular parameters were recorded during a 2-min pretask baseline, a 10-min stressful exposure, and over a 5-min post-task baseline. The intertask correlations between the cold pressor and digit scan increased with prolonged exposure and were higher for almost all of the systolic BP measurements than for the diastolic measurements. After prolonged exposure, the hemodynamic mechanisms of BP elevations during the digit scan shifted from an increase in both cardiac output and peripheral vascular resistance to solely an increase in peripheral vascular resistance. Increased peripheral vascular resistance was the consistent cause of the BP elevations with the cold pressor. Accordingly, the hemodynamic shift on the part of the digit scan seemed to heighten the intertask BP correlations. Some other factors influencing the intertask BP correlations are also discussed.     

Factor Structure,Validity, and Reliability of the Japanese Version of the Balanced Index of Psychological Mindedness (BIPM)

This study examined the measurement properties of the Balanced Index of Psychological Mindedness (BIPM) among the Japanese population. Exploratory factor analysis was conducted to examine the factor structure of the BIPM (Study 1) among 464 university students, and confirmatory factor analysis examined the validity and reliability of the BIPM (Study 2) among 321 university students. Additionally, the mitigation effect of psychological mindedness (PM) for depressive symptoms was examined. The results showed a two-factor structure (Interest and Insight) similar to the original BIPM. The BIPM was negatively correlated with the alexithymia score and positively correlated with the Psychological Mindedness Scale and Openness. It was also significantly correlated with future depressive symptoms. The BIPM is useful for measuring PM in the Japanese population. Additionally, this study suggests clinical applications of PM in psychotherapy and the treatment effect mechanism of cognitive behavioral therapy.     

Evaluation of pre-operative anxiety and propofol-induced sedation using newly proposed indices of finger vascular tone

Abstract: This study examined estimates of finger vascular tone, obtained from photoplethysmography. Normalized and double‐normalized pulse volume (NPV and DNPV), blood volume (BV), and pulse volume (PV) were obtained in 2 male and 7 female middle‐aged patients at an outpatient office 1–3 days before an operation and in the operating room before and after anesthesia by propofol. There was a preoperative decrease in NPV, and the propofol injection yielded a moderate increase in BV. The latter seemed to contribute to a decrease in DNPV. A partial correlation controlling for body mass index was observed between the change in NPV and the dose of propofol; a larger reduction in NPV before anesthesia compared with the control condition was accompanied by the need for a greater infusion of propofol for sedation. In conclusion, among the measures examined, NPV appears to be the best indicator of heightened arteriolar vascular tone.     

Influence of rumination and self‐efficacy on depression in Japanese undergraduate nursing students

Researchers have suggested that self‐efficacy can predict and prevent depression, while negative coping strategies, as typified by rumination, can lead to depression. The authors examined the relationship between self‐efficacy, rumination, and depression in Japanese nursing students. The result of a structural equation model showed that rumination, but not self‐efficacy, predicted depression. The result of simultaneous multiple group analysis indicated that there was homogeneity within the same path diagram between genders. The result implied that stress management should focus on controlling the degree of rumination rather than self‐efficacy in order to efficiently maintain the mental health of Japanese nursing students.     

Theory of mind enhances preference for fairness

The purpose of the current study was to examine the role of theory of mind in fairness-related behavior in preschoolers and to introduce a tool for examining fairness-related behavior in children. A total of 68 preschoolers played the Ultimatum Game in a face-to-face setting. Acquisition of theory of mind was defined as the understanding of false beliefs using the Sally-Anne task. The results showed that preschoolers who had acquired theory of mind proposed higher mean offers than children who had not acquired theory of mind. These findings imply that the ability to infer the mental states of others plays an important role in fairness-related behavior.