The existence and specificity of a characteristic behavioral syndrome among patients with temporal lobe epilepsy (TLE) remains controversial. The behavioral pattern of many epilepsy patients differs from that of age-, sex-, and socioeconomic-matched control subjects. Patients with TLE and other forms of epilepsy can experience changes in cognitive function, personality, affect, and drive-related behavior (e.g., libido, aggression). Biologic factors (e.g., underlying brain pathology, epileptogenic process, localization and lateralization, recurrent seizures, family history), antiepileptic drugs, and psychosocial factors interact pathogenically. Their roles vary among patients and among different neurobehavioral disorders. Behavioral changes occur in some epilepsy patients. However, the question of whether specific behavioral changes occur with different seizure types or epilepsy syndromes remains unanswered. For example, behavioral changes can occur in patients with absence epilepsy, juvenile myoclonic epilepsy, frontal lobe epilepsy, and tonic-clonic seizures. Many of these behavioral changes overlap with features of the purported TLE syndrome. We lack a clear delineation of the spectrum, frequency, and severity of changes in well-characterized partial and primary generalized epilepsy syndromes. Furthermore, the relative roles and the interplay among pathogenic factors remain poorly defined.