Dominance assertion in male chimpanzees (Pan troglodytes)

The social relations of three adult males in a captive chimpanzee group were evaluated for 12 months. The observations encompassed a period of transition in the dominance hierarchy providing an opportunity to assess behavioral patterns involved in the initiation of status changes. This study shows that dominance in the chimpanzee is expressed primarily through ritualized and non-contact behavior rather than by overt aggression. In particular, display behavior is important for indicating dominance rank, in communicating aggressive intent, and as a prelude to status struggles. The functional relationships between status, displays and other socio-sexual behavior patterns are presented.     

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.     

Effects of fluprazine (DU 27716) upon aggressive and sexual behavior of testosterone-treated female rats

Female rats, chronically treated with Testosterone Propionate (TP), were injected with Fluprazine (DU 27716) or saline and tested for social aggression, masculine and feminine sexual behavior. Fluprazine-treated females were less aggressive than saline-treated females, as indicated by a shift from offensive to less offensive parameters of aggression. At the same time, mounting in Fluprazine-treated females was almost totally abolished, both in aggression tests and in tests for sexual behavior. Feminine sexual responses increased during aggressive encounters but were slightly inhibited when females were confronted with sexually active males. Females treated with Fluprazine and tested for mounting with a receptive female showed a substantial increase of offensive aggression directed at the receptive stimulus female. It is concluded that Fluprazine does not selectively inhibit offensive aggression in TP-treated female rats.     

Relationship between poverty and health among adolescents

Although the effect of low socioeconomic status on the health of adolescents has been documented, the mechanism by which this occurs is not well understood. Furthermore, improving adolescent health through public health policy typically requires the presence of one or more modifiable risk factors which can be targeted for intervention. In spite of the well-documented negative associations between poverty and health, few modifiable risk factors have been identified. This study used the Evans-Stoddart Model of Health and Well-Being as a framework to examine data on 1,759 adolescents, aged 12 to 19, collected as part of the 1994 National Population Health Survey. Results not only confirm the relationship between income and health, but suggest how the pathway operates through the social environment, lifestyle differences, access to health care, and a reduced sense of self-esteem and self-mastery. Bivariate and multivariate analyses found positive associations between physical activity levels and self-esteem and mastery. We interpret these findings as preliminary evidence that it might be possible to buffer the impact of poverty on health through policies which increase physical activity levels among those living in poverty. Such policies could also include a secondary goal of increasing the activity levels among inactive adolescents who are not living in poverty, as they will derive benefits from this increase, both psychologically and physiologically.     

Cognitive behavior therapy in treatment-naive children and adolescents with obsessive-compulsive disorder: an open trial

This work aims is to evaluate the therapeutic efficacy of cognitive behavior therapy (CBT) in pediatric patients with obsessive-compulsive disorder (OCD) who had not previously been treated with either pharmacotherapy or psychotherapy and who remained medication-free during CBT. Sixteen OCD outpatients, 8-17 years of age, were treated in a 12-week open trial with manualized CBT. Target symptoms were rated at two-week intervals with the Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS), the National Institute of Mental Health Global Obsessive-Compulsive Scale (NIMH Global), the Clinical Global Impression Scale (CGI), and the Hamilton Anxiety Rating Scale (Ham-A). Statistical analyses showed a significant benefit for treatment. Ten patients experienced at least a 50% reduction in symptoms on the CY-BOCS; seven were asymptomatic on the NIMH Global. These results build on previous reports that CBT may be effective in the acute treatment of pediatric OCD. Further, the results of this study suggest that CBT can be efficacious in alleviating OCD symptoms in the absence of pharmacotherapy. These results must be considered preliminary, given the small sample size and open administration of treatment.