Fear, Memory, and Stress Hormones: Too Much and at the Wrong Time

Individuals with post-traumatic stress disorder (PTSD) have two different memory impairments: increased memory for the event (manifested by intrusive recollections and flashbacks), and a fear that has spread beyond the cues that are related to the trauma. We know that glucocorticoids affect reaction to later stress (JW Psychiatry Mar 5 2012). These investigators used fear conditioning in mice as a model in investigating glucocorticoids' role in PTSD-like memory impairments and hippocampal–amygdalar activation.

The researchers injected corticosterone in the hippocampus of mice placed within a specific context (conditioning cage) and subjected to a fearful stimulus (footshock) that was either preceded or not by a cue (tone). Mice that did not …