Basal ganglia

Paired nerve cell clusters deep within the cerebrum (the main mass of the brain) and upper part of the brainstem. The basal ganglia play a vital part in producing smooth, continuous muscular actions and in stopping and starting movement. Any disease or degeneration affecting the basal ganglia and their connections may lead to the appearance of involuntary movements, trembling, and weakness, as occur in Parkinson’s disease.

 

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