Discriminação simples auditiva em Macaco-prego (Cebus apella)

Abstract

The acquisition of generalized discriminative relational repertoires represents a complex discriminative capability in the interaction on any species with its environment, having, for much time, being considered to be exclusively human. There are few researches on this capability in non-human primates in the auditory modality, and even less about their multimodal discriminatory repertoire, which characterizes much of the complex discriminative human behavior. This study investigated the possibility of a capuchin monkey (Cebus apella) to learn to respond appropriately to different acoustic stimuli by the use of a simple discrimination procedure. The subject was exposed to five pairs acoustic stimuli: each pair was always composed of one sound with a predominance of high frequencies and another of low frequencies; one of them with a function of positive stimulus (S +) and the other of negative stimulus (S-). The criteria adopted for the presentation of a new pair of stimuli was the achievement of a rate of response for the (S-) equal of inferior more than 25% of the rate for the (S +), for five consecutive sessions. The subject reached the criteria for all five pairs of stimuli. The effects of learning set and the physical properties of the stimuli are discussed, as well as procedural differences in regard to previous studies. These results suggest the possibility of using capuchin monkey as an animal model in research on complex discriminative repertoires.