Elevation and reduction of plasma tryptophan and their effects on aggression and perceptual sensitivity in normal males

Data from experimental animals suggest that 5-hydroxytryptamine (5HT) may have an inhibitory effect on aggression, while clinical studies have found a correlation between pathological aggression and low brain 5HT. To investigate this relationship further we used amino acid mixtures designed to raise or lower the levels of the 5HT precursor, tryptophan. Normal male subjects were given tryptophan-depleted, balanced, or tryptophan-supplemented ammo acid mixtures and tested for aggression 5 hours later. The balanced amino acid mixture served as a control for the tryptophan depletion and supplementation. Testing for aggression was done using the Buss paradigm in which subjects deliver electric shocks to a (nonexistent) partner in response to stimulus tones. Duration and intensity of shock delivered were the measures of aggression, while responsivity to the stimulus tones was the measure of perceptual sensitivity. Neither tryptophan supplementation nor tryptophan depletion had any effect on these measures of aggression or perceptual sensitivity. We conclude that raising or lowering the synthesis of brain 5HT through alterations in tryptophan availability does not influence aggression in normal males as measured by the Buss task.     

An empirically derived scoring system for intermale aggression in mice

Scoring systems used to assess intermale aggression have been characterized by arbitrary scales and wide variability in the behaviors selected for measurement. The use of such different systems severely limits the ability of investigators to make meaningful comparisons among studies and indicates that there is a need for a common, statistically derived evaluative system for intermale aggression. We measured the frequency and duration of five major components of agonistic behavior exhibited by intact males toward olfactory bulbectomized stimulus males and then analyzed the data using a number of univariate and multivariate procedures. The results were used to generate two statistically based scoring systems, one a short-form index and the other a composite index for more detailed studies of aggression. It is hoped that these statistically derived systems will be adopted by other investigators to increase methodological congruence in the field.     

Aggressive behavior in the free-ranging rhesus monkeys of kathmandu,nepal

We present a composite sample of the aggressive behavior of free-ranging rhesus monkeys (Macaca mulatta), recorded at two temples in Kathmandu, Nepal. We analyze the total number and the rate per monkey of threats, chases, attacks, fights, and aggressive acts directed at other species (principally humans), in order to elucidate social dynamics of the troop as a whole. Our 1,506 hours of observation were divided among the four seasons; between a.m. and p.m.; and among a temple yard, two parklands, and a forested garden. We found seasonal patterns to be the most important correlates of aggressive behavior. Habitat was a modulating influence, and time of day was the least important factor. Rates of aggression were generally higher per male monkey than per female. In terms of total aggression recorded, however, females instigated significantly more than males, both in encounters between monkeys and in aggression against other species. This finding is consistent with the females' greater numbers in the troop and with their lifelong membership in the troop. Analysis of behavior by social groups, rather than by individual rates, points up the iomportance of adult females and their social stability in troop behavior.     

Romantic Conflict Narratives in Emerging Adult Couples: Viewpoint and Gender Matter

Healthy romantic relationships entail understanding the needs of the self and other when interpreting conflict events. Yet how couples make meaning around specific conflicts and their capacity to reflect on their own and their partners’ unmet needs is understudied. Using narratives, we examined destructive (e.g., extreme anger and break-up anxiety) and constructive (e.g., perspective taking) interpretations of past romantic conflicts in 80 emerging adult heterosexual couples and the extent to which such interpretations varied by viewpoint and gender. Couple members were interviewed separately about two conflict episodes in which their partner did not meet their needs (victim viewpoint) and two episodes in which they did not meet their partners’ needs (perpetrator viewpoint). As anticipated, destructive interpretations were more evident in the victim viewpoint and for female couple members. In contrast, within constructive interpretations, the use of insight was greater in the perpetrator than the victim viewpoint. Although perspective taking was expected to be more common in the perpetrator viewpoint and in female narratives, this was not the case, as this type of constructive interpretation was infrequent in narratives about conflict. The findings revealed aspects of meaning making that might be useful to mental health professionals concerned with building skills to improve romantic competence in emerging adult couples.     

Challenging anxious cognitions or accepting them? Exploring the efficacy of the cognitive elements of cognitive behaviour therapy and acceptance and commitment therapy in the reduction of children's fear of the dark

Anxiety is highly prevalent in pre-adolescent children. Distorted cognitions are characteristic for dysfunctional levels of anxiety. However, applying cognitive elements in pre-adolescent children cannot be fully ascertained, as it is not until adolescence before children can apply logical and abstract reasoning in a sophisticated manner. Cognitive behaviour therapy (CBT) and acceptance and commitment therapy (ACT) both target distorted cognitions. Whereas CBT encourages children to change the content of negative cognitions by applying cognitive restructuring, ACT stimulates youth to have a more accepting attitude towards these thoughts by applying cognitive defusion. The current study examined the efficacy of applying cognitive elements and compared the cognitive elements of CBT and ACT in pre-adolescent children. We included no behavioural elements to specifically study the developmental appropriateness of the cognitive elements in this age group. Highly anxious children, aged 8–12 years were randomised to a 30-minute cognitive restructuring (n = 21) or cognitive defusion intervention (n = 22). Subjective fear of the dark levels, behavioural darkness toleration, and comprehension and fun associated with the interventions were assessed. Both interventions had a significantly positive impact on children's fear of the dark. Cognitive restructuring led to more favourable results on subjective fear than cognitive defusion, no differences were found for darkness toleration.     

Correction to: Teleological epistemology

Philosophical Studies - In Section 3 of the original version, the Weak Evidentialist Norm is given as follows: ‘For every S, p and t, S’s coming to know p at t is...     

Fathers’ Paternity Leave-Taking and Children’s Perceptions of Father-Child Relationships in the United States

Paternity leave-taking is believed to benefit children by encouraging father-child bonding after a birth and enabling commitments to fathers’ engagement. Yet, no known U.S. studies have directly focused on the associations between paternity leave-taking and children’s reports of father-child relationships. Understanding the potential consequences of paternity leave-taking in the United States is particularly important given the lack of a national paid parental leave policy. The present study uses five waves of data on 1319 families, largely socioeconomically disadvantaged, from the Fragile Families and Child Wellbeing Study to analyze the associations between paternity leave-taking and 9-year-old children’s reports of their father-child relationships. We also assess the extent to which these associations are mediated by fathers’ engagement, co-parenting quality, parental relationship satisfaction, and fathers’ identities. Results indicate that leave-taking, and particularly 2 weeks or more of leave, is positively associated with children’s perceptions of fathers’ involvement, father-child closeness, and father-child communication. The associations are explained, at least in part, by fathers’ engagement, parental relationship satisfaction, and father identities. Overall, results highlight the linked lives of fathers and their children, and they suggest that increased attention on improving opportunities for parental leave in the United States may help to strengthen families by nurturing higher quality father-child relationships.

     

Interpretation of Baladeva and Yamunā at Harivaṃśa 83

International Journal of Hindu Studies - In Harivaṃśa chapter 83, Kṛṣṇa’s brother Baladeva changes the course of the river Yamunā, using his plough. This...     

Moderating Loss Aversion: Loss Aversion Has Moderators,But Reports of its Death are Greatly Exaggerated

Loss aversion, the principle that losses impact decision making more than equivalent gains, is a fundamental idea in consumer behavior and decision making, though its existence has recently been called into question. Across five unique samples (N_total = 17,720), we tested several moderators of loss aversion, which supported a preference construction account. Across studies, more domain knowledge and experience were associated with lower loss aversion, though people of all knowledge and experience levels were loss averse. Among car buyers, those who knew more about a particular car attribute (e.g., fuel economy) were less loss averse for that attribute but not other attributes (e.g., comfort), consistent with the idea that people with less attribute knowledge are more likely to construct preferences, thereby increasing loss aversion. Additionally, older consumers were more loss averse across different loss aversion measures and studies. We discuss implications for several accounts of loss aversion, including accounts rooted in status quo bias, emotion, or ownership. In addition to discovering loss aversion moderators, we cast doubt on recent claims that loss aversion is a fallacy or is fully explained by status quo bias, risk aversion, or the educated laboratory samples often used to study loss aversion.