ABSTRACT

Background The association of male pubertal testosterone with social dominance and physical aggression was studied in a population sample of boys followed from age 6 to 13 years to understand the origin of the links between violent behavior and gonadal hormones.

Method Physical aggression was assessed from the end of kindergarten to the end of elementary school by teachers and peers (aged 6 to 12 years). Social dominance and testosterone levels were assessed at 13 years of age during a 1-day visit to a laboratory with four unfamiliar peers.

Results Boys perceived as socially dominant by unfamiliar peers were found to have concurrently higher levels of testosterone than boys perceived as less socially dominant. In contrast, boys who had a history of high physical aggression, from age 6 to 12, were found to have lower testosterone levels at age 13 compared with boys with no history of high physical aggression. The former were also failing in school and were unpopular with their peers.