Date of Award

Summer 8-2011

Degree Type

Masters Thesis

Degree Name

Master of Arts (MA)



Committee Chair

Mitchell E. Berman

Committee Chair Department


Committee Member 2

Randolph C. Arnau

Committee Member 2 Department


Committee Member 3

Bradley A. Green

Committee Member 3 Department



Studies of humans show an inconsistent relationship between aggression and T, as well as between T and antisocial and self-aggressive behavior. Other biological variables, including cortisol and brain serotonin, have been implicated as having an effect on the regulation of antisocial and self-aggressive behavior. Researchers have suggested that inconsistencies in the T-aggression relation may be due to the presence of moderating variables. One theory posits that serotonin moderates the relation between T and aggression. The purpose of this study was to examine the relationship between T (as well as cortisol and 5-HT) and aggression-related constructs. A second purpose was to determine if 5-HT functioning moderates the relation between T and aggression and related constructs. Participants for the current study were derived from two archival datasets. Participants (N = 98) who completed the Life History of Aggression semi-structured interview were also administered placebo or paroxetine. Cortisol, free and total testosterone, and 5-HT activity were measured by assaying serum samples via venipuncture at four time points. Results showed that cortisol was negatively correlated with antisocial behavior and that blunted cortisol response (i.e., decreased 5-HT activity) predicted increased aggressive behavior, both of which were consistent with expectations. However, results also showed that increased aggressive and antisocial behavior predicted lower total testosterone levels, which was contrary to hypotheses. No moderating effects for 5-HT were found. The implications and limitations of the current study are discussed. Suggestions for future research are also noted.

Doctoral dissertation: