[Disruption of food-getting movements after removal of the motor or premotor zone of the cerebral cortex in cats].

Instrumental food-procuring movements were studied in cats before and after unilateral or bilateral ablation of the motor or premotor cortical area. It is shown that unilateral impairment of the motor area affects the strength and accuracy of movements of the contralateral fore-leg, whereas the ablation of the premotor area leads to a slowing down of movements and breaking of a goal-directed movement into separate components. Bilataral ablation of the motor area irreversibly abolished the instrumental reflex. The ablation of the premotor cortex destroyed the animal's reaction to the sound signal, but food-procuring movements of the fore-legs were disturbed only temporarily. The obtained data are discussed on the basis of the concept that in cats the above cortical areas play different roles in the organization of goal directed behaviour.