[Activity of motor cortex neurons in the cat during a conditioned postural change reflex]

Spike activity of unitary motor cortex (area 4) neurons was recorded during performance of conditioned reflex postural adjustment in cats. Changes in activity of most neurons (increase of discharge frequency) correlated with conditioned-reflex supporting movement of the forelimb. These neuronal reactions had specific polycomponent patterns and preceded the conditional movements by 50-600 ms. Neuronal reactions connected with erroneous positive movement responses to differential stimuli and spontaneous "interstimular" movements had the same direction but were less intensive and occurred in most cases synchronously with these movements. Neuronal reactions and postural adjustments simultaneously disappeared during reflex extinction. The proposed method of elaboration of conditioned reflex of postural adjustments permits obtaining standard natural coordinated forelimb movements which form the necessary initial component of more complex behavioral reactions.