motor seizure, abnormal electrical activity that arises initially in a localized motor area of the cerebral cortex. The manifestations depend on the site of the abnormal electrical activity, such as tonic contractures of the thumb caused by excessive discharges in the motor area of the cortex controlling the first digit or chewing movements resulting from discharges in the lower part of the motor strip controlling mastication. The disturbance may spread, resulting in generalized convulsion, or it may end in a shower of clonic movements. See also epilepsy, focal seizure.
