Generalized Identity Matching to Sample after Multiple-Exemplar Training in Capuchin Monkeys

UMMS Affiliation

Intellectual and Developmental Disabilities Research Center; Shriver Center

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Experimental Analysis of Behavior | Psychiatry and Psychology


A multiple-exemplar identity matching-to-sample baseline was established to encourage development of generalized IDMTS performances in three adult male capuchins. Mask (blank comparison) or Shuffled S- procedures were used to promote select (sample-S+) control in baseline relations and to assess stimulus control relations in generalized IDMTS tests. The IDMTS baseline comprised eight 3-stimulus sets or four 4-stimulus sets. Probe trials with new stimulus sets were substituted for baseline sets in successive testing sessions and subsequently converted to new baseline relations. All monkeys exhibited high accuracy on generalized IDMTS tests. A monkey who was given the Mask procedure in training and tests showed generalized IDMTS with select relations predominating. Two monkeys who were given training and testing with the Shuffled S- procedure performed somewhat better on Shuffled S- IDMTS test trials than on test trials that contained non-shuffled test IDMTS trials thus suggesting that exclusion of familiar nonmatching comparison stimuli from baseline in Shuffled S-test trials contributed to the higher accuracy scores with the former procedures. Development of select relations appeared to be a positive predictor of development of generalized IDMTS.

DOI of Published Version



Brino AL, Galvão OF, Picanço CR, Barros RS, Souza CB, Goulart PR, McIlvane WJ. Generalized Identity Matching to Sample after Multiple-Exemplar Training in Capuchin Monkeys. Psychol Rec. 2014 Dec;64(4):693-702. PubMed PMID: 25435596; PubMed Central PMCID: PMC4243937. Link to article on publisher's site

Journal/Book/Conference Title

The Psychological record

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