Contralateral Supplementary Motor Area Research Articles

Contrasting neuronal activity in the ipsilateral and contralateral supplementary motor areas in relation to a movement of monkey's distal hindlimb

Recordings were made from the supplementary motor areas in both cortical hemispheres of a monkey trained to press a foot pedal. As a result of appropriate limb fixation, the movement was performed with activity predominantly in distal muscles of the right hindlimb. Forty-three percent of contralateral neurons showed movement-related activity. In contrast, only 9% of ipsilateral neurons were active and magnitudes of their activity were smaller.

Interaction between forced grasping and a learned precision grip after ablation of the supplementary motor area

Monkeys were trained to compress and release a force transducer held between the thumb and forefinger. Immediately following ablation of the contralateral supplementary motor area a grasp reflex produced a disturbance of the learned precision grip characterized by an increase in mean grasping force, an increase in the rate of prehensile force application and an inability to release the strain gauge. No change was observed in the same learned grip with the ipsilateral hand.

Pyramidal tract activity associated with a conditioned hand movement in the monkey.

Pyramidal tract activity associated with a conditioned hand movement in the monkey.