Dissociable contributions of the amygdala and ventral hippocampus to stress-induced changes in defensive behavior.

Background: Severe stress can produce multiple persistent changes in defensive behavior relevant to psychiatric illness. While much is known about the circuits supporting stress-induced associative fear, how stress-induced circuit plasticity supports non-associative changes in defensive behavior remains unclear.

Methods: Mice were exposed to an acute severe stressor, and subsequently, both associative and non-associative defensive behavioral responses were assessed.