Neuronal activity of cat sensorimotor cortical area was studied during performance of movements of grasping a visual goal appearing for a short time. Characteristics and the pattern of neuronal discharge became stabilized in the process of animal training and did not depend on the time of goal presentation, absence or presence of the reinforcement under preservation of animal's motor reaction. Changes in responses were observed in situations of uncertainty: at 50% of reinforcement probability and (or) at successful performance of the motor reaction in half of cases.