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D000293:Adolescent; D000328:Adult; D000818:Animals; D001245:Association Learning; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D003210:Concept Formation; D003463:Cues; D004193:Discrimination Learning; D000882:Haplorhini; D006801:Humans; D011582:Psychological Theory; D012718:Set, Psychology; D014796:Visual Perception