title: Rapid cognitive flexibility of rhesus macaques performing psychophysical task-switching.
abstract: Three rhesus monkeys (Macaca mulatta) performed a simultaneous chaining task in which stimuli had to be sorted according to their visual properties. Each stimulus could vary independently along two dimensions (luminosity and radius), and a cue indicating which dimension to sort by was random trial to trial. These rapid and unpredictable changes constitute a task-switching paradigm, in which subjects must encode task demands and shift to whichever task-set is presently activated. In contrast to the widely reported task-switching delay observed in human studies, our subjects show no appreciable reduction in reaction times following a switch in the task requirements. Also, in contrast to the results of studies on human subjects, monkeys experienced enduring interference from trial-irrelevant stimulus features, even after exhaustive training. These results are consistent with a small but growing body of evidence that task-switching in rhesus macaques differs in basic ways from the pattern of behavior reported in studies of human cognition. Given the importance of task-switching paradigms in cognitive and clinical assessment, and the frequency with which corresponding animal models rely on non-human primates, understanding these differences in behavior is essential to the comparative study of cognitive impairment.
authors.affiliation: Department of Psychology, Columbia University, New York, NY, USA.
authors.forename: Ema
authors.initials: E
authors.lastname: Avdagic
authors.forename: Greg
authors.initials: G
authors.lastname: Jensen
authors.forename: Drew
authors.initials: D
authors.lastname: Altschul
authors.forename: Herbert S
authors.initials: HS
authors.lastname: Terrace
mesh_terms: D000818:Animals; D003071:Cognition; D003463:Cues; D008253:Macaca mulatta / Q000523:psychology*; D008297:Male; D010775:Photic Stimulation; D011597:Psychomotor Performance; D011930:Reaction Time