Initiating a computer-assisted enrichment system for captive chimpanzees (2000)

Ross, S. K., Bloomsmith, M. A., Baker, K. C. et al.

Abstract

The joystick apparatus was used without significant decrease throughout 2-hour sessions and across the 3-month duration of the study. ... Food rewards were automatically dispensed upon completion of each trial. Juvenile subjects spent 20% of the 2-hour sessions utilizing the computer-joystick system, whereas their elderly cagemates used it very little (0.8%).