Abstract

My interest in posture and its central nervous control dates from my early days in neurology. That was also the time of the epidemic of encephalitis lethargica. A few years ago I came upon some old photographs dating from this period and among them were several of two small boys suffering from the after-effects of encephalitis with severe disorders of postural control. Each of these boys, if placed on an ordinary chair would let his body fall forward and would "roll" off the chair and lie motionless on the floor. In more recent years it has been shown experimentally that similar symptoms in monkeys are associated with bilateral lesions of the globus pallidus; in post-encephalitic patients of long standing degenerative changes are present in the pallida, but it now seems likely that deficiency of the neuro-transmitter, dopamine, may bear as much responsibility for their symptoms as anatomical lesions. Neurology was slow to appreciate the contribution of the basal ganglia to postural activity.