Localization of an experimental hypothalamic and midbrain syndrome simulating sleep

The origin and significance of sleep have been a source of speculation throughout the centuries, and the problem of abnormal sleep as a disease entity has long aroused the curiosity of medical men. It was only half a century ago, however, that Mauthner (lS90), after studying clinical cases of Nona and Wernicke’s disease, postulated a specific locality in the brain as a critical source for sleep regulation. This center he designated the area of transition between the midbrain and the diencephalon. More recently, von Economo (’29, ’30, ’31), from his study of encephalitis lethargica during the Vienna epidemic of 1916-17 and 1920-21, came to conclusions similar to those of Mauthner and proposed certain rostro-caudal boundaries to delimit the center : the most caudal limit being immediately rostra1 to the oculomotor iiucleus and the frontal limit reaching as far as the region of the striatum.