Regional aspects of the delay of acquisition conditioned avoidance responding by chlorpromazine

Chlorpromazine injected into the amygdala, septum, or caudate delayed the acquisition of a one-way active avoidance response. Injections into nine other brain areas were inactive. Following a standard dose of chlorpromazine at its ED50 for delaying avoidance acquisition, tissue levels of chlorpromazine from those animals displaying reduced acquisition were significantly higher in the caudate and amygdala than from animals not demonstrating a drug effect.