Pigeons acquire multiple categories in parallel via associative learning: A parallel to human word learning?

Abstract

Might there be parallels between category learning in animals and word learning in children? To examine this possibility, we devised a new associative learning technique for teaching pigeons to sort 128 photographs of objects into 16 human language categories. We found that pigeons learned all 16 categories in parallel, they perceived the perceptual coherence of the different object categories, and they generalized their categorization behavior to novel photographs from the training categories. More detailed analyses of the factors that predict trial-by-trial learning implicated a number of factors that may shape learning. First, we found considerable trial-by-trial dependency of pigeons’ categorization responses, consistent with several recent studies that invoke this dependency to claim that humans acquire words via symbolic or inferential mechanisms; this finding suggests that such dependencies may also arise in associative systems. Second, our trial-by-trial analyses divulged seemingly irrelevant aspects of the categorization task, like the spatial location of the report responses, which influenced learning. Third, those trial-by-trial analyses also supported the possibility that learning may be determined both by strengthening correct stimulus-response associations and by weakening incorrect stimulus-response associations. The parallel between all these findings and important aspects of human word learning suggests that associative learning mechanisms may play a much stronger part in complex human behavior than is commonly believed.

Orthographic processing in pigeons ( Columba livia )

“…Critically, the conceptualization account can also explain the bigram frequency, OLD20, and transposed-letter data, which, in essence, are all measures of how closely stimuli within one class or category resemble one another (e.g., the bigram frequencies of words) and how closely they approximate stimuli in a different class (e.g., the orthographic similarity of nonwords to words). In this context, our data support the view that pigeons' conceptualization abilities make them an ideal animal model with which to investigate the early stages of human word learning (35).…”

Conceptualization in pigeons: The evolution of a paradigm

“…This new paradigm surely advances our understanding of the complexity and capacity of associative learning processes in animals and promotes the application of those processes to important problems lying well beyond the traditional realm of animal conditioning. Moreover, the tight laboratory control that is offered by this paradigm also permits the conduct of detailed trial-by-trial analyses that may be capable of disclosing the intricacy and richness of associative learning, possibly affording us the opportunity to study the interplay between the strengthening and weakening of associative connections (for details of these encouraging results, see Wasserman et al, 2015).…”

“…We developed and deployed another 16-category paradigm to achieve those ends (Wasserman, Brooks, & McMurray, 2015).…”

Separating the effect of reward from corrective feedback during learning in patients with Parkinson’s disease

“…First, we calculated a Z score for every item performed using a binomial test against chance (50%). The Z score was calculated using the following equation (as in Wasserman, Brooks, & McMurray, 2015):…”