My research is/has been supported by a number of different agencies including:
The University of Connecticut Research Foundation; Claude Pepper – Research Development Core; the National Science Foundation (NSF); and the National Institute on Aging (NIA), we are very appreciative of this support!
Many of the learning and memory changes found during aging and in Alzheimer’s Disease are linked to neurobiological changes in the hippocampus. The research examines the manner in which these molecular changes contribute to overall hippocampal function, and subsequently to memory deficits. As part of this research we have tested hearing and vision in rats.
Data from human amnesiacs and animal models indicates that the hippocampus plays an important role in turning events we experience into long term memories. We are examining the process of encoding and consolidating new information in both young and aged animals.
Neural Network Interpretation-Inputs:
Local Field Potentials (LFP) within the hippocampal system (similar to EEG that is taken from the brain surface) indicate rhythmic input activity at different band frequencies. We focus on the relationship between theta and gamma waves and information processing. Recently we have shown regional differences within the hippocampus in the cognitive correlates of these waves.
Neural Network Interpretation – Outputs:
Monitoring the activity of neurons within the hippocampus with tetrodes has shown that hippocampal cells code for the rat’s location in the environment. We are examining the plasticity of this system, i.e. how this hippocampal representation of the environment changes as the animals learn new things in a familiar environment; and how this differs across sub-regions of the hippocampus.
Competition Between Different Brain Systems:
There are multiple parallel information processing systems in the brain. The hippocampus allows the animal to navigate to a certain place, while the dorsal striatum causes motor response based navigation. We are examining the mechanisms underlying why, depending upon the condition, one system influences behavior more than the other. We hypothesize that the activity and synchrony in a system is the decisive factor. Populations of neurons in the hippocampus and striatum are recorded while rats perform a navigation task with a mixture of spatial and motor response trials.