title: Similar stimulus features control visual classification in orangutans and rhesus monkeys.
abstract: Many species classify images according to visual attributes. In pigeons, local features may disproportionately control classification, whereas in primates global features may exert greater control. In the absence of explicitly comparative studies, in which different species are tested with the same stimuli under similar conditions, it is not possible to determine how much of the variation in the control of classification is due to species differences and how much is due to differences in the stimuli, training, or testing conditions. We tested rhesus monkeys (Macaca mulatta) and orangutans (Pongo pygmaeus and Pongo abelii) in identical tests in which images were modified to determine which stimulus features controlled classification. Monkeys and orangutans were trained to classify full color images of birds, fish, flowers, and people; they were later given generalization tests in which images were novel, black and white, black and white line drawings, or scrambled. Classification in these primate species was controlled by multiple stimulus attributes, both global and local, and the species behaved similarly.
authors.affiliation: Emory University and Yerkes National Primate Research Center, Atlanta, GA.
authors.forename: Rachel F L
authors.initials: RF
authors.lastname: Diamond
authors.affiliation: Zoo Atlanta, Atlanta, GA.|Dian Fossey Gorilla Fund International, Atlanta, GA.
authors.forename: Tara S
authors.initials: TS
authors.lastname: Stoinski
authors.affiliation: Zoo Atlanta, Atlanta, GA.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Mickelberg
authors.affiliation: Laboratory of Neuropsychology, National Institute of Mental Health, NIH.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Basile
authors.affiliation: Zoo Atlanta, Atlanta, GA.|Bucknell University, Lewisburg, PA.
authors.forename: Regina Paxton
authors.initials: RP
authors.lastname: Gazes
authors.affiliation: Providence College, Providence, RI.
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Templer
authors.affiliation: Emory University and Yerkes National Primate Research Center, Atlanta, GA.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Hampton
mesh_terms: D000818:Animals; D003210:Concept Formation; D005260:Female; D008253:Macaca mulatta / Q000523:psychology; D008297:Male; D010775:Photic Stimulation; D057080:Pongo abelii / Q000523:psychology; D011148:Pongo pygmaeus / Q000523:psychology; D014796:Visual Perception
keywords: classification; orangutan; rhesus monkey; vision