Testosterone, a steroid hormone, contributes to aggressive behavior in males, but the neural circuits through which testosterone exerts these effects have not been clear.
Prior studies found that the administration of a single dose of testosterone influenced brain circuit function. Surprisingly, those studies were conducted exclusively in women.
Researchers, led by Dr. Justin Carré, sought to rectify that gender gap by conducting a study of the effects of testosterone on the brain's response to threat cues in healthy men. They focused their attention on brain structures that mediate threat processing and aggressive behavior, including the amygdala, hypothalamus, and periaqueductal gray.