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.
Ell, S. W., Helie, S., & Hutchinson, S. (in press). Contributions of the putamen to cognitive function. In A. Costa and E. Villalba (Eds.), Horizons in Neuroscience Research: Vol. 7. Nova.
Ell, S.W., Hutchinson, S., & Maddox, W.T. (in press). Explicit and procedural-learning based systems of perceptual category learning. In N. Seel (Ed.), Encyclopedia of the Sciences of Learning. New York: Springer.
Ell, S.W., & Zilioli, M. (in press). Categorical learning. In N. Seel (Ed.), Encyclopedia of the Sciences of Learning. New York: Springer.
Ell, S.W., Cosley, B., McCoy, S.K. (2011). When bad stress goes good: Increased threat reactivity to a psychosocial stressor predicts improved category learning performance. Psychonomic Bulletin & Review, 18, 96-102.
Ell, S. W., Weinstein, A., & Ivry, R. B. (2010). Rule-based categorization deficits in focal basal ganglia lesion and Parkinson’s disease patients. Neuropsychologia, 48, 2974-2986.
Schnyer, D.M., Maddox, W.T., Ell, S.W., Davis, S., Pacheco, J., Verfaellie, M. (2009). Prefrontal contributions to rule-based and information-integration category learning. Neuropsychologia, 47, 2995-3006.
Ell, S. W., Ing, D. A., & Maddox, W. T. (2009). Criterial noise effects on rule-based category learning: The impact of delayed feedback. Attention, Perception, & Psychophysics, 71, 1263-1275.
Ell, S.W., & Ivry, R.B. (2008). Cerebellar pathology does not impair performance on identification or categorization tasks. Journal of the International Neuropsychological Society, 14, 760-770.