An update on the search for symmetry in nonhumans

摘要: Sidman et al.'s (1982) failure to find evidence for symmetry (bidirectional associations between stimuli) in monkeys and baboons set the stage decades of work on emergent relations nonhumans. They attributed use procedures that did not (1) promote stimulus control based relation sample correct comparison (2) reduce by irrelevant features. Previous reviews nonhumans indicated multiple exemplar training successive matching might encourage appropriate control. This review examined 16 studies investigated 94 subjects, including pigeons, rats, capuchin monkeys, baboons. Several used alternative minimize sources control, many combined with other procedural modifications. Symmetry was observed approximately 30% subjects. Studies reported strongest matching-to-sample included both symbolic identity relations, finding mixed employed methods. These highlight challenge creating need assess underlying positive demonstrations.