Elsevier -- Philadelphia, PA, October 22, 2008 – Cortisol helps our bodies cope with stress, but what about its effects on the brain? A new study by Cohen and colleagues, appearing in the October 15th issue of Biological Psychiatry, suggests that the answer to this question is complex. In an animal model of posttraumatic stress disorder (PTSD), high doses of a cortisol-related substance, corticosterone, prevented negative consequences of stress exposure, including increased startle response and behavioral freezing when exposed to reminders of the stress. However, low-dose corticosterone potentiated these responses. This finding suggests that corticosterone levels may influence both vulnerability and resilience in a dose-dependent manner through its involvement in memory processes.
