Abstract # 29:

Scheduled for Saturday, September 19, 2009 11:45 AM-11:55 AM: Session 3 (Del Mar Room) Oral Presentation


E. L. Nelson1, C. M. Metevier2 and M. A. Novak1,2
1University of Massachusetts , Neuroscience and Behavior Graduate Program, Amherst, MA 01003, USA, 2Department of Psychology, University of Massachusetts Amherst, MA 01003, USA

Motor planning was examined in adult rhesus macaques [N=7] with an elevated spoon task. Monkeys had no prior spoon experience. In this task, the spoon was baited with a semi-solid food (applesauce or yoghurt) and placed on a wooden apparatus that supported the bowl and handle ends of the spoon. The handle was oriented to the left or right on alternating trials. On easy trials, the handle was oriented towards the monkey’s preferred hand and on difficult trials towards the non-preferred hand according to baseline hand preference. Spoon grips were classified as radial (thumb towards bowl), ulnar (thumb towards handle end), or bowl (hand in food). Efficient planning required the monkey to make radial grips either by alternating hands or adjusting body position relative to the apparatus. Each test session consisted of 6 trials, and monkeys were tested until criterion, 10/12 radial grips within 2 sessions, or a maximum of 6 sessions. Two-tailed binomial tests were used for statistical analyses. At the individual level, 5 of 7 monkeys reached criterion [p<0.05], but at differing rates ranging from 2 to 6 sessions. Within these monkeys, radial grips increased from 67% [p>0.05] to 100% [p<0.01] on easy trials and from 33% [p>0.05] to 87% [p<0.01] on difficult trials over sessions. These data highlight variation in initial motor planning ability and learning effective motor plans in monkeys.