Rhesus monkeys (Macaca mulatta), video tasks, and implications for stimulus-response spatial contiguity

Abstract

Recent reports (Iwai, Yaginuma, & Mishkin, 1986; Yaginuma & Iwai, 1986) have supported the earlier conclusion by Meyer, Treichler, and Meyer (1965) and by Stollnitz (1965) that the efficiency of primate learning is compromised to the degree that there is spatial discontiguity between discriminanda and the locus of response. The research reported in this article calls for a reconsideration of this conclusion. Two rhesus monkeys (Macaca mulatta) easily mastered precise control of a joystick to respond to a variety of computer-generated targets despite the fact that the joystick was located 9 to 18 cm from the video screen. We hold that stimulus-response contiguity is a significant parameter of learning only to the degree that the monkey visually attends to the directional movements of its hand in order to displace discriminanda as in the Wisconsin General Test Apparatus. If, instead, attention is focused on the effects of the hand's movement rather than on the hand itself, stimulus-response contiguity is no longer a primary parameter of learning. The implications of this work for mirror-guided studies are discussed.