Beginning in the 1980s, a series of studies in rodents conducted by Robert Sapolsky and other investigators suggested that the CA3 area of the hippocampus, a brain region implicated in mood and memory, was particularly vulnerable to stress. When analyzing the brain tissue in detail, they reported loss of nerve cells called neurons with stress. Other rodent studies described reductions in the birth of new neurons in the hippocampus associated with stress.
Collectively, these studies suggest that stress-related disorders, such as depression and posttraumatic stress disorder, might be associated with hippocampal volume loss. This hypothesis is supported by numerous studies reporting reduced hippocampal volume in depressed patients.
Read the entire release from Biological Psychiatry.