Hormones

The primary endocrine hormone implicated in violent behavior

Testosterone, an androgenic steroid hormone produced by the testes in males and in trace amounts by the ovaries and adrenal glands in females.

How testosterone modulates neural structures to increase aggression thresholds

It acts directly on the limbic system, altering sensitivity within the amygdala to increase emotional reactivity and lower the threshold for aggressive responses.

The demographic correlation explained by testosterone tracking

Explains why males across almost all human cultures statistically demonstrate significantly higher rates of physical violence and dominant behaviors than females.

The role of the glucocorticoid hormone Cortisol in behavioral regulation

Released by the adrenal cortex during prolonged stress, it promotes systemic anxiety, fear, and behavioral inhibition to keep impulses in check.

The core claim of the Dual-Hormone Hypothesis

Elevated levels of testosterone only lead to overt physical violence and dominant aggression when baseline levels of cortisol are abnormally low.

The behavioral outcome of having high testosterone matched with low cortisol

The individual lacks normal stress-induced behavioral inhibition, leaving the activating, dominance-seeking effects of testosterone entirely unchecked.