Jane and Bud Smith Distinguished Chair;
Distinguished Chair in Neuroscience and the Jane and Bud Smith Distinguished Chair
MD, University of Maryland
Cognitive Neuroscience of Semantic Memory
Dr. Hart's research interests have focused on the neural basis of semantic memory in the human brain. His work spanning several decades has focused on identifying the organization of semantic memory in the human brain by proposing that there is both a categorical and featural structure to object memory that exists in multiple memory systems in the brain. His laboratory's recent studies have used functional neuroimaging and electrophysiological investigations to explore the neural mechanisms underlying combining these components of an object together to form an integrated object memory. They recently reported that one neural mechanism by which retrieval of this object memory can occur is via synchronizing beta brain rhythms that are modulated by the thalamus. This mechanism is modulated by the pre-SMA and caudate to facilitate effective semantic memory retrieval. These findings have led to his group's proposal of the Neural Hybrid Model of Semantic Memory to account for how the brain stores and retrieves object memory. He is now investigating object memory and word finding deficits in multiple disease states in terms of both diagnosing and designing treatment options based on this model including PTSD, MS, dementia, and those with TBI who are aging such as retired NFL players.
Calley, C., Motes, M., Chiang, H-S., Buhl, V., Spence, J., Abdi, H., Anand, R., Maguire, M., Estevez, L. Briggs, R., Freeman, T., Kraut, M., Hart, J. Jr. Threat as a feature in visual semantic object memory. Human Brain Mapping, 34(8):1096-105, 2013.
Strain, J.F., Didebhani, N., Cullum, C.M., Mansinghani, S., Conover, H., Kraut, M., Hart, J., Womack, K.B. Depressive symptoms and white matter dysfunction in retired NFL players with concussion history. Neurology, 81(1):25-32, 2013.
Hart, J., Kraut, M., Womack, K., Strain, J., Didebhani, N., Bartz, E., Conover, H., Mansinghani, S., Lu, H., Cullum, C.M. Neuroimaging of cognitive dysfunction and depression in aging retired NFL players: A cross-sectional study. JAMA Neurology, 70(3):326-35, 2013.
DeLaRosa, B. L., Spence, J. S., Shakal, S. K., Motes, M. A., Calley, C. S., Calley, V. I., & Kraut, M. A. (2014). Electrophysiological spatiotemporal dynamics during implicit visual threat processing. Brain and Cognition, 91, 54-61.
Hart, J., Maguire, M., Motes, M. Mudar, R., Cjiang, H-S., Womack, K., Kraut, M. Semantic memory retrieval circuit: Role of BA6 and thalamus. Brain and Language, 126(1):89-98, 2013.