Abstract # 167:

Scheduled for Sunday, September 14, 2014 07:00 PM-09:00 PM: Session 22 (Decatur B) Poster Presentation


T. A. Evans and M. J. Beran
Georgia State University, Language Research Center, University Plaza, Atlanta, GA 30302, USA
     Capuchin monkeys and rhesus monkeys performed a computerized inhibition task in which delaying a joystick response rather than starting the task immediately allowed their eventual response to be more efficient. Monkeys earned food pellets for eliminating different sized arrays of target objects using a digital eraser. When a trial began, the eraser automatically grew in size as long as monkeys did not attempt to move it. Thus, there was a trade-off between quickly getting started on the task and quickly/easily eliminating targets with a larger eraser. Monkeys of both species succeeded in this task by inhibiting moving the eraser for as long as 10 seconds, and they allowed the eraser to grow larger for successively larger target arrays. In a second experiment, these monkeys performed four variants of the eraser task in which the eraser either grew or shrunk in size over time, and in which it was most beneficial to either act immediately or to inhibit a response (depending on the relative size of the target area and the onscreen ‘gateway’ that led to that area). Individuals of both species learned to tailor their responses to the temporal and spatial restraints of each task variant, rather than always obtaining the largest eraser or always delaying their response as long as possible. This demonstrated that these monkeys’ responses were flexible and cognitively controlled.