This report refers to a 51 year old man with the clinical features of central alveolar hypoventilation (CAH). Polysomnographic recordings showed periodic breathing and central apnoeas associated with abnormal oscillations of systemic arterial pressure and heart rate during all sleep stages. Oxygen administration during sleep reduced hypoxia, while the periodic breathing and arterial pressure oscillations persisted. The authors suggest that an impairment of the brain structures that play a role in homeostatic adjustment of autonomic functions in connection with the sleep-wake cycle, is responsible for the unusual sleep-related disturbances shown by this patient.