POSTCENTRAL NEURONS OF ALERT MONKEYS ACTIVATED BY THE CONTACT OF THE HAND WITH OBJECTS OTHER THAN THE MONKEYS OWN BODY

In the caudal postcentral finger region near or in the anterior bank o f the intraparietal sulcus of alert monkeys, we found neurons that wer e activated selectively by the contact of the hand to certain common o bjects such as bottle brushes, acrylic plates, parts of the stabilized monkey's chair, etc. All of these neurons were not activated when the monkey's hand was contacted with the monkey's own body. We concluded that these neurons are concerned with the haptic discrimination of com mon objects with the selectivity to one of various material variables of objects, and that the process involves differentiation of the objec t from the animal's own body.