My research program, broadly defined, investigates the cognitive mechanisms underlying human learning and memory. In particular, research in my lab focuses on category learning – that is, the process of establishing a memory trace that improves the efficiency of assigning novel objects to contrasting groups. Category learning is a particularly useful focus as it provides a model for investigating many key theoretical issues of general relevance to human learning and memory. More specifically, my research program investigates: 1) the nature and interaction of multiple learning systems; 2) rule-guided behavior; 3) the relationship between social stress and cognition; and 4) characterizing and improving cognitive function in individuals with Parkinson’s disease. In pursuit of these research topics, I use a number of methodological approaches to investigate category learning including traditional cognitive experiments with college-aged and elderly individuals, computational modeling, psychophysiology, and behavioral research with neuropsychological populations.