POTENTIAL RELATED TO NO-GO REACTION IN GO NO-GO HAND MOVEMENT WITH DISCRIMINATION BETWEEN TONE STIMULI OF DIFFERENT FREQUENCIES IN THE MONKEY

Monkeys were trained for go/no-go reaction-timed hand movement with discrimination between tone stimuli of different frequencies, and field potentials related to the discriminative movement were recorded with electrodes implanted in various cortical areas and analysed by averaging procedure. In the cortex of the dorsal bank of the principal sulcus,, surface-negative, depth-positive (s-N, d-P) potentials were recorded specifically on the no-go trial. The same monkey was also examined for go/no-go reaction-time hand movement with color discrimination. In the same monkey, the potentials related to the on-go reaction on the auditory stimulus were recorded in the rostral part of the dorsal bank of the principal sulcus, whereas the S-N, d-P potentials on the no-go visual stimulus were observed in the caudal part of the same bank. It is suggested that the dorsal bank of the principal sulcus is essentially related to the integrative functions such as judgement not to move and suppression of motor execution, and that different loci in this cortical area are respectively active for the functions of different sensory modalities.