Categorizing physically dissimilar stimuli such as objects, words, sounds, and other sensory events into the same class is fundamental to meaning, comprehension, and other aspects of cognitive development and functioning. This application studies fundamental learning processes that underlie stimulus-class formation and the resultant emergence of novel behavior, a characteristic of normal human development that is often deficient and in need of behavioral remediation in individuals with developmental disabilities. The broad objective is to demonstrate that even in the absence of language, establishing particular conditional relations between specific pairs of stimuli via reinforcement versus non-reinforcement yields sets of interchangeable stimuli (viz., stimulus classes) as evidenced by the subsequent ability to respond appropriately to novel, untrained combinations of those stimuli. The project aims are to show how such learning yields well-defined instances of emergent behavior rarely (if ever) seen in non-human animals, rigorously test the predictions of a model which assumes that ordinal position is coded as part of a stimulus'functional characteristics, and test the hypothesis that routinely non-reinforcing certain stimulus combinations while reinforcing other combinations generates stimulus classes containing the elements of the latter. In all of the proposed research, non-verbal animals possessing other, established categorization abilities (pigeons) will be concurrently trained on go/no-go matching tasks in which certain sequences of sample and comparison stimuli end in reinforcement whereas others do not. Later, stimulus-class formation will be tested by presenting novel sequences of those same stimuli. Besides revealing emergent effects, these tests will simultaneously evaluate the ordinal-specific properties of the hypothesized functional stimuli and the importance of continual exposure to non-reinforcement (as well as reinforcement) throughout training. Together, the expected pattern of findings will demonstrate that basic, general learning processes - in particular, the reinforcement contingencies used to establish conditional stimulus relations - can generate stimulus classes even in the absence of language and its neural structures and pathways.

Public Health Relevance

Understanding that disparate things like objects, pictures, and written and spoken words can be related is fundamental to meaning, categorization, language comprehension and other characteristics of normal development and functioning. This application examines basic reinforcement and stimulus control processes that provide a foundation for such understanding and for yielding novel, generative behavior. The project underscores the possible involvement of an unrecognized or easily overlooked feature of stimuli - their temporal or ordinal properties - that may help to explain variation in equivalence training outcomes observed with normal and intellectually disabled populations. Clarifying the nature and influence of these processes is the first step toward the development of comprehensive diagnostic tests and effective treatment interventions for individuals with intellectual impairments. In addition, the discrimination paradigm used in the project has some distinctive advantages over more commonly used behavioral procedures in the developmental disabilities field, thus providing a promising alternative for establishing stimulus classes when other approaches fail.

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Research Project (R01)
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Study Section
Biobehavioral Regulation, Learning and Ethology Study Section (BRLE)
Program Officer
Freund, Lisa S
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Purdue University
Schools of Arts and Sciences
West Lafayette
United States
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Swisher, Melissa; Urcuioli, Peter J (2018) Reflexivity without identity matching training: A first demonstration. J Exp Anal Behav 109:125-147
Swisher, Melissa; Urcuioli, Peter J (2015) Symmetry in the pigeon with sample and comparison stimuli in different locations. II. J Exp Anal Behav 104:119-32
Urcuioli, Peter J (2015) A successful search for symmetry (and other derived relations) in the conditional discriminations of pigeons(). Conductual 3:4-25
Urcuioli, Peter J; Swisher, Melissa J (2015) Transitive and anti-transitive emergent relations in pigeons: support for a theory of stimulus-class formation. Behav Processes 112:49-60
Zentall, Thomas R; Wasserman, Edward A; Urcuioli, Peter J (2014) Associative concept learning in animals. J Exp Anal Behav 101:130-51
Campos, HeloĆ­sa Cursi; Urcuioli, Peter J; Swisher, Melissa (2014) Concurrent identity training is not necessary for associative symmetry in successive matching. J Exp Anal Behav 101:10-25
Urcuioli, Peter J; Wasserman, Edward A; Zentall, Thomas R (2014) ASSOCIATIVE CONCEPT LEARNING IN ANIMALS: ISSUES AND OPPORTUNITIES. J Exp Anal Behav 101:165-170
Urcuioli, Peter J; Jones, B Max; Lionello-DeNolf, Karen M (2013) Evidence for response membership in stimulus classes by pigeons. J Exp Anal Behav 99:129-49
Swisher, Melissa; Urcuioli, Peter J (2013) Symmetry in the pigeon with sample and comparison stimuli in different locations. J Exp Anal Behav 100:49-60
Urcuioli, Peter J; Swisher, Melissa (2012) Emergent identity matching after successive matching training. II: Reflexivity or transitivity. J Exp Anal Behav 97:5-27

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