Responsiveness of monkey primary somatosensory cortical neurons to peripheral stimulation depends on 'motor-set'.

Responses evoked by vibrotactile stimuli in primary somatosensory cortical neurons were studied under two conditions. In the first, the vibrotactile stimulus was the trigger for a movement of the stimulated hand, while in the second, the motor response had been extinguished. Thus, responses of the same neuron could be compared during different motor sets. Neurons in area 3a and 1, but not area 3b, often exhibited different responses depending on motor set. These findings support the view that responses of many somatosensory cortical neurons are modulated by central as well as peripheral influences and are dependent upon the context in which the stimulus occurs.