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Research on same–different categorization has shown that mastery of tasks of this kind can be strongly affected by the number of items in the training arrays—for both humans and nonhuman animals. Evidence for two-item same–different categorization in pigeons is decidedly mixed: although some investigations have succeeded, others have failed. To date, no research has documented successful conditional same–different categorization using just two items, nor has research explored how pigeons’ responses in this paradigm might be influenced by perceptual characteristics of the training stimuli. Through a series of methodological modifications, we provide the first successful documentation that pigeons can perform two-item conditional same–different categorization to a high degree of accuracy; further, they can do so without the support of item repetition. We also show for the first time that the perceptual disparity between the items in pairs of different stimuli plays a key part in pigeons’ same–different categorization performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved)
Source: Journal of Experimental Psychology: Animal Behavior Processes - Category: Zoology Source Type: research