Structural and Functional Neuroplasticity in Relation to Traumatic Stress

The body's stress response is an essential adaptive and protective mechanism to cope with threatening situations. However, chronic or traumatic stress leads to structural and functional alterations in the traumatized brain. We argue for a building-block effect: Exposure to different types of traumatic events increases the probability of developing posttraumatic stress disorder (PTSD), via incremental enlargement of a fear network. We summarize evidence of brain changes in PTSD, including recent results from research on animal models of stress-related neuroplastic remodeling, with an emphasis on structural and functional changes in the hippocampus, the amygdala, and the medial prefrontal cortex.