Stress-induced changes in the glucocorticoid system may be toxic for hippocampal cells in animals. Recently, neurogenesis has been shown in the rat, the primate, and the human hippocampus. Because chronic stress is associated with some neuropsychiatric disorders, including schizophrenia, it is possible that an imbalance in the normal turnover of hippocampal cells plays a role in the pathophysiology not only of schizophrenia but also of other neuropsychiatric disorders that involve high levels of stress. New therapeutic possibilities arise if such a process is proven to occur.