Sara N. Burke, Ph.D.
Department of Neuroscience
University of Florida
1149 Newell Drive
PO Box 100244
Gainesville, FL 32611-0244
Office Phone: (352) 294-4979
Aging, Entorhinal Cortex, Hippocampus, Memory, Neurophysiology, Perirhinal Cortex
The focus of my research continues to be on determining the neurobiology of age-related memory loss. My lab addresses this question using multiple levels of analysis that include molecular imaging techniques, high-channel count in vivo neurophysiology, and behavioral assessment. Particularly, we are taking the novel approach of trying to understand how aging impacts communication across brain areas that are critical for adaptive behaviors. Age-associated cognitive impairments do not result from alterations to brain structures in isolation. To fully understand cognitive aging, it is therefore imperative to examine how brain areas interact. A powerful tool for pin-pointing disruptions in the complex neural systems that produce cognitive dysfunction during normal aging is the careful analysis of behavior. Therefore, all of my research projects begin with an extensive cognitive test battery, including tests of spatial memory, working memory, stimulus recognition and sensory perception. Following, a careful characterization of behavior, the primary methods I use to assay the neurobiological basis of age-associated cognitive decline are single-cell imaging techniques and in vivo high-density recordings of single neurons from behaving rats. A strength of this approach is that the neurobiology of age-related memory loss is examined at multiple levels. Behavioral analysis along with advanced imaging and physiological techniques provides a multiplicative understanding of the loci of circuit disruptions by linking specific physiological features to cognitive performance.
Research Focus & Aims:
Broadly, my NIH-funded research program examines the neurobiological origins of age-related cognitive decline, in a rodent model. To do this, we use multiple levels of analysis that span from gene expression to high-level behavioral analysis. Recently, my research has expanded beyond examining how advanced age impacts single brain regions to determining how large-scale interactions among different areas are altered over the lifespan (Hernandez et al., 2015). Understanding the neurobiology of memory impairments in advanced age presents a unique challenge, as memory processes are distributed throughout the brain and a fundamental gap exists in our understanding of how these structures interact. To pursue this research agenda, my laboratory has implemented novel behavioral assays that more closely model ‘real-world’ behaviors in humans (Hernandez et al., 2015), as well as new methods that incorporate anatomical tracing with gene expression analysis to quantify measures of functional connectivity between regions with single-cell resolution.
My research is also aimed at testing potential therapeutic strategies for improving health outcomes in the elderly. In young animals, dynamic hippocampal activity patterns support learning and memory. I have been involved in a series of papers that show how behavior-dependent modulation of hippocampal activity is compromised in aged animals to produce memory deficits. Moreover, we have shown that altering NMDA receptor currents with the Alzheimer’s disease therapeutic memantine can restore experience-dependent plasticity in aged memory-impaired rats (Burke et al., 2008). Currently, my laboratory has also been measuring the extent that a diet-based intervention can improve hippocampal-dependent memory in aged animals. These experiments are being supported by a Pilot Award from the UF Pepper Older Americans for Independence Center.