Research in the Cellular Neurophysiology Laboratory is primarily directed towards understanding the cellular and molecular mechanisms of synaptic integration and long-term synaptic plasticity. We have focused our attention on neurons and synapses in the hippocampus, an area of the brain that plays an important role in learning and memory. The hippocampus is also of interest because it has a low seizure threshold and plays an important function in human epilepsy. Our research uses quantitative electrophysiological, optical imaging, and computer modeling techniques.
We are investigating the properties and mechanisms of long-term potentiation (LTP), a synaptic substrate for aspects of memory. This interest has led us to investigate not only the basic mechanisms of synaptic transmission but also the basic mechanisms of synaptic integration in the dendrites of the postsynaptic neuron. For example, we have recently used fluorescence imaging techniques and dendritic patch-clamp recordings to identify the types and location of voltage-gated Na+ and Ca2+ channels in dendrites of hippocampal pyramidal neurons. This work is complemented by our computer modeling studies in which we attempt to reconstruct the biophysical properties of hippocampal neurons based on our experimental data. Our studies of LTP have included investigations of the pre- and/or postsynaptic locus of change during LTP and the cellular mechanisms of induction. We hope that these investigations will enhance our understanding of the synaptic mechanisms of learning and memory and provide insight into the function of the hippocampus in the behaving animal.