9509117 Bronzino The primary hypothesis to be investigated is that, during normal development, the maturation of peak hippocampal theta frequency is related primarily to changes in the modulation of dentate granule cell activity, and not due to alterations in cellular excitability of CA1 pyramidal cells. Another hypothesis to be tested is that the biocoherence index is an effective measure of the changing interrelationships that occur between CA1 and the dentate gyrus during development of hippocampal activity. In previous research surgical and recording techniques were developed that allow a quantitative examination of the development of inhibitory/facilitatory modulation of the dentate granule cell population. Modeling techniques will be used to characterize the development of the rat hippocampal EEG during the early postnatal (15-22 days) period of development. The studies are expected to provide new knowledge on the interactions that occur between hippocampal neural systems responsible for the generation of hippocampal EEG patters as the animal iteracts with its environment during the early postnatal period of development. The results will provide new approaches to probe questions related to the maturation of neural circuits and developmental patterns of the EEG in behaving animals. The project provides a high quality research experience to undergraduate students through their active participation in surgery and recording techniques and to the development of quantitative and computational techniques applied to problems in biology. ***
