Chapter 25 – MULTIPLE SYSTEMS OF PERCEPTUAL CATEGORY LEARNING: THEORY AND COGNITIVE TESTS

The first neurobiologically detailed theory of multiple systems in category learning, called COVIS, was originally conceived in 1998. COVIS, which is now well established, postulates two systems that compete throughout learning—a frontal-based declarative system that uses logical reasoning and depends on working memory and executive attention, and a basal ganglia-mediated system that uses procedural-learning. The procedural system can learn a wide variety of category structures, but it learns in a slow incremental fashion and is highly dependent on reliable and immediate feedback. In contrast, the declarative rule-based (RB) system can learn a fairly small set of category structures quickly—specifically, those structures that can be learned via a logical reasoning process. These two systems learn simultaneously, but as long as RB strategies lead to successful performance, the declarative system inhibits the procedural system. This theory is described in detail and a variety of cognitive behavioral and cognitive neuroscience experiments are reviewed that test some parameter-free a priori predictions made by COVIS.