jackson

John Hughlings Jackson asserted in "On certain relations of the cerebrum and cerebellum on rigidity of hemiplegia and of paralysis agitans" (1899) that the cause of the parkinsonian tremor lay in the cerebellum. He also asserted that parkinsonian tremor was caused by damage to the cerebral hemisphere from a release phenomenon caused by the unopposed action of the cerebellum. He believed that rigidity was a confluent tremor.