Training and performance of rhesus monkeys as operators in a compensatory manual control system.

Two rhesus monkeys were trained as operators in a compensatory manual control system similar to systems used in human studies. Training procedures used to shape compensatory tracking behavior included a multiple shock-avoidance technique, the gradual introduction of the system input, and sharpening visual stimulus control of tracking behavior. Time-on-target scores for the monkeys were 95% to 98% while responding to three different frequency bandwidths of the system input. As frequency bandwidth increased, no significant increase in error was noted, the monkeys returned the target element to the center target area at increasing rates, and the number of shocks delivered to each subject remained low. Bode plots and stripouts of input, output, and error signals resembled those typically obtained in human studies. Through extrapolations based on nonhuman primate performance, the conclusion was that the task development and training procedures of the present study provided a means for estimating human performance in manual control systems under environmental stress or in hazardous environments.