Psychobiology of ictal aggression.
1. Aggression in animals has been classified into a number of stereotyped behavioral responses on the basis of the psychosocial environment in which it occurs. Many such responses can be either replicated or blocked by stimulation or ablation of selected sites in the brain, especially in the hypothalamus or amygdala. Stimulation of the amygdala or the hypothalamus in a limited number of humans has produced agitation, anger, or rage. Ablation of the amygdala has reduced aggression in violent patients. However, the ictal nature of episodic aggression in these patients has not been proven. 2. The diagnosis and classification of epileptic seizures is based on their characteristic clinical manifestations and electrical patterns. Independent objective markers of ictal events need to be identified. Epileptic seizures are characterized by stereotyped nondirected behavior, especially at onset. The more organized, directed, and modifiable by the environment the behavior is, the less likely it is epilepsy. 3. Ictal aggression can be classified into primary and secondary ictal aggression, resistive violence, and postictal psychosis. Few alleged cases of ictal violence or aggression fulfill criteria for ictal events; most which do are examples of resistive violence. 4. If animal models can be developed which exhibit spontaneous paroxysmal stereotypical aggression, they may be used to improve our understanding of the classification and pathophysiology of ictal aggression.