The effects of stress on behavior can be grouped into three general categories: (1) mild stress can induce or potentiate a variety of behaviors such as eating, aggression, and sexual behavior; (2) more severe stress may disrupt behavior by making it repetitious, less finely tuned to the environment and stereotyped; (3) severe stress can also totally suppress behavior. These effects of stress, which have been reported to occur in virtually all species, including man, may represent an attempt by the organism to reduce or eliminate the deleterious effects of the stress. In this sense, these behaviors represent a form of self-therapy.