Abstract # 2455 Event # 135:

Scheduled for Saturday, June 21, 2008 09:45 AM-09:55 AM: Session 14 (Meeting Room 2DEF) Oral Presentation

Reversal-learning perseveration correlates to repetitive behavior in nonhuman primates

P. G. Judge, D. W. Evans, K. K. Schroepfer and A. C. Gross
Bucknell University, Psychology Department and Program in Animal Behavior, Lewisburg, PA 17837, USA
     In humans, repetitive ritualistic behavior symptomatic of obsessive-compulsive disorder and autism is associated with perseverative responses on executive function tasks, particularly those involving rule switching. We tested for a similar relationship in other primates by correlating rates of self-directed behavior, a measure of repetitive behavior, to performance on a reversal-learning task. Five hours of focal observations were collected on five lion-tailed macaques (Macaca silenus), three squirrel monkeys (Saimiri sciureus), and six brown capuchin monkeys (Cebus apella) to obtain rates of self-directed behavior (scratch, autogroom, self touch and manipulation) within their respective social groups. The same animals were also tested on a reversal-learning task in which they were presented with a black and grey square on a touch screen and trained to touch the black square. Once animals chose the black square significantly above chance levels, reward contingencies were reversed and animals were rewarded for selecting the grey square. Reversal learning was assessed as the number of 60-trial testing sessions necessary for animals to select the grey square significantly more than chance. Performance on the reversal-learning task was positively correlated to self-directed behavior in that animals exhibiting higher rates of self-directed behavior in their groups perseverated on the old rule and required more sessions to achieve reversal [r(14)=0.76, p<0.005]. Results suggest continuity between humans and other primates in the link between executive functioning and repetitive behavior.