The localization of function in the cerebral and in the cerebellar cortex has doubtless been the main cause of this progress, and has proceeded poi passu with an extended insight into the structure and connexions of the parts concerned.
A reeling gait, oscillations of the body which impart a zigzag direction to the walk, difficulty in standing, owing to unsteadiness of limb, are common in cerebellar disease.
On the other hand, congenital defect amounting to absence of one cerebellar hemisphere has been found to occasion practically no symptoms whatsoever.
Vertigo is a frequent result of cerebellar injury: animals indicate it by their actions; patients describe it.
To interpret this vertigo, appeal must be made to disturbances, other than cerebellar, which likewise occasion vertigo.