Research interests

Research in the lab investigates the cognitive and neural mechanisms of learning and memory. In particular, we focus on the ability of individuals to learn novel categories – that is, the process by which people acquire the ability to assign objects in the environment to different groups. We use a number of methodological approaches in our research, including traditional cognitive experiments with college-aged and elderly individuals, experiments with individuals with neurodegenerative disorders (e.g., Parkinson's disease) and brain injury due to stroke, and computational modeling. The lab's research encompasses four central issues in category learning: 1) The single versus multiple systems debate; 2) The role of working memory and attentional processes; 3) The utility of conceptualizing category learning as a motor skill; and 4) Investigating the neurobiological substrates of category learning.

Publications

• 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.
• Ell, S. W., Marchant, N. L., & Ivry, R. B. (2006). Focal putamen lesions impair learning in rule-based, but not information-integration categorization tasks. Neuropsychologia, 44, 1737-1751.
• Ashby, F. G., Ell, S. W., Valentin, V. V., & Casale, M. B. (2005). FROST: A distributed neurocomputational model of working memory maintenance. Journal of Cognitive Neuroscience, 17, 1728-1743.
• Ashby, F. G., Noble, S., Filoteo, V., Waldron, E., & Ell, S. W. (2003). Category learning deficits in Parkinson’s disease. Neuropsychology, 17, 115-124.
• Ashby, F. G., & Ell, S. W. (2001). The neurobiology of human category learning. Trends in Cognitive Sciences, 5, 181-225.