[Participation of the head of the caudate nucleus of the dog in mechanisms of conditioned reflex postural reorganization].

On the model of instrumental defensive reflexes, components of conditioned postural reorganization were analyzed in 5 dogs before and after preliminary stimulation of the caudate nucleus head (CNH) of the contralateral (with respect to the active limb) hemisphere. The disturbance of normal function of the striatum caused by electric stimulation of CNH or by pathological changes elicited by a prolonged (during two-four years) CNH stimulation led to a significant change in the main mechanisms of posture reorganization: disturbances of the centre of gravity transfer and sharp rise of time of weight redistribution to the supporting limbs. Changes elicited by caudate pathology and by CNH stimulation went in the same direction. It is suggested that disturbances in the initiation of voluntary movement in striate pathology, are mainly caused by disturbances in posture initiation and reorganization, necessary for movement execution.