Altered states of consciousness in disorders of daytime sleepiness.

Patients with daytime sleepiness present altered states of consciousness. The occurrence of these states impairs their professional, social and familial activities and may threaten life itself. The automatic behavior syndrome is characterized by continuation of mechanical activity and complete amnesia. Episodes lasting from a few seconds to several hours are correlated with repetitive micro-sleep periods. During cataplectic attacks, patients may have a meshing of reality with hallucinatory dream contents. Sleep-induced apnea may lead to abnormal movement and abnormal ambulation during sleep as well as hallucinations in the early morning. These altered states of consciousness must be considered as diagnostic indexes in differentiating epileptic syndromes from syndromes of daytime sleepiness.