The genetic modulation of cognitive and brain change in midlife by measuring effects of neurotransmission and neurotrophic SNPs, including the Alzheimer susceptibility gene APOE.
Dr. Greenwood received her PhD at SUNY Stony Brook under Michael Gazzaniga. She went on to a post-doctoral fellowship at the West Haven VA and Yale University to learn event-related potential techniques with Truett Allison and W.R. Goff and conduct basic research on somatic event-related potentials. She eventually moved to Catholic University in Washington, DC, to study attention using both electrophysiology and behavioral methods in healthy aging and Alzheimer's disease. There, she and Raja Parasuraman developed a large-scale study of the genetics of cognitive aging using both information processing and standardized neuropsychological assessments of cognition as a function of Alzheimer’s susceptibility genes and neurotransmission genes. These efforts have evolved to include investigations into ways to ameliorate cognitive aging and broadened into investigations of the principles important in successful cognitive training in general. We are currently focused on (a) understanding the relation between cognitive change and brain change over the course of cognitive training, and (b) understanding how training-related cognitive change is related to change in cortical thickness, white matter integrity, and functioning connectivity, particularly in ventral and dorsal attention networks.
Dr. Greenwood has research interests in cognitive aging and the genetics of cognitive aging which she examines using behavioral, neuroimaging, and genetic methods. Specifically she studies the modulation by normal genetic variation of attention, working memory, and the role of attention in forming and maintaining mental representations in working memory. She and Parasuraman are conducting a longitudinal study of the genetics of cognitive change in midlife. In collaboration with Drs. Parasuraman, Thompson, and Peterson, and James Bicksel (Inova Memory Center) she recently began a randomized controlled trial of cognitive training in healthy older people and people diagnosed with mild cognitive impairment.
Greenwood, P. M., Lin, M. K., Sundararajan, R., Fryxell, K. J., & Parasuraman, R. (2009). Synergistic effects of genetic variation in nicotinic and muscarinic receptors on visual attention but not working memory. Proceeding of the Natlonal Academy of Sciences, USA, 106(9), 3633-3638.
Greenwood, P. M., Sundararajan, R., Lin, M. K., Kumar, R., Fryxell, K. J., & Parasuraman, R. (2009). Both a nicotinic SNP and a noradrenergic SNP modulate working memory performance when attention is manipulated. Journal Cognitive Neuroscience, 21(11) 2139-53.
Greenwood, P.M. (2007). Functional plasticity in cognitive aging: Review and hypothesis. Neuropsychology, 21, 657-673. (Published with open peer commentary).
Clarke, E., Andrews, A., Espeseth, T. Parasuraman, R., & Greenwood, P.M. Visuospatial attention influences mental representation during working memory maintenance as reflected in the CDA. Paper presented at American Psychological Association, Boston, May, 2010.
McGarry, W., Greenwood, P.M., & Parasuraman, R. The change in distribution of visuospatial attention with aging. Society for Neuroscience, November, 2010.
Greenwood, P.M., Lin, M-K, Fryxell, K.J, & Parasuraman, R. Normal variation in BDNF and COMT genes and individual differences in working memory in old age. Society for Neuroscience, November, 2010.
Dr. Greenwood's research, along with that of others, was discussed in "Mason Experts Attack Alzheimer’s on All Fronts" in the Mason Gazette.