title: Category number impacts rule-based and information-integration category learning: a reassessment of evidence for dissociable category-learning systems.
abstract: Researchers have proposed that an explicit reasoning system is responsible for learning rule-based category structures and that a separate implicit, procedural-learning system is responsible for learning information-integration category structures. As evidence for this multiple-system hypothesis, researchers report a dissociation based on category-number manipulations in which rule-based category learning is worse when the category is composed of 4, rather than 2, response categories; however, information-integration category learning is unaffected by category-number manipulations. We argue that within the reported category-number manipulations, there exists a critical confound: Perceptual clusters used to construct the categories are spread apart in the 4-category condition relative to the 2-category one. The present research shows that when this confound is eliminated, performance on information-integration category learning is worse for 4 categories than for 2 categories, and this finding is demonstrated across 2 different information-integration category structures. Furthermore, model-based analyses indicate that a single-system learning model accounts well for both the original findings and the updated experimental findings reported here.
authors: Department of Psychology, St. Mary's College of Maryland, St. Mary’s City, MD 20686, USA. rdstanton@smcm.edu
authors: Roger D
authors: RD
authors: Stanton
authors: Robert M
authors: RM
authors: Nosofsky
mesh_terms: D000704:Analysis of Variance; D001244:Association; D032882:Comprehension / Q000502:physiology*; D003210:Concept Formation; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D011939:Mental Recall / Q000502:physiology; D010775:Photic Stimulation; D011237:Predictive Value of Tests; D011336:Probability; D013334:Students; D014495:Universities