抄録
A new method was developed to detect the reinforcing effect of visual stimulus presentation (color photo or light) on the lever-pressing behavior of infant Japanese monkeys. In this experiment, each 1-hr session was devided into two alternating periods. During one period (presentation period), if the subject pressed the lever a visual stimulus resulted, but during the other period (non-presentation period), pressing the lever did not result in a visual stimulus. The duration of a visual stimulus presented was dependent on the duration of lever-pressing. The relative time allocation to lever-pressing was greater during the presentation period than during the non-presentation period although total response rate varied between sessions. This method makes it possible to detect such a weak reinforcing effect as of sensory stimuli which previous methods have failed to detect.
