The Department of Anatomy & Neurobiology seminar will host guest speaker Dr. Benjamin Gunn, Project Scientist at University of California, Irvine

An analysis of the primary hippocampal circuit implications and applications

Despite intense interest in hippocampal contributions to behavior, surprisingly little is known about how cortical signals are processed across even the basic multi-stage circuit. Here, I will describe the first input/output relationship for the primary hippocampal circuit. Results identify a novel role for recurrent CA3 activity in driving throughput that challenges the notion of the tri-synaptic circuit, while the presence of low pass filters dictates the nature of effective input frequencies and patterns. Although the simplest circuit operation, signal throughput is critical for the execution of more complex processes required for hippocampus-dependent memory processing — how these findings place constraints upon circuit performance and the potential for different operational states will be discussed. These findings open the way to novel analyses of how the hippocampus and its contributions to behavior may be influenced in physiological and pathophysiological states. In this regard, I will provide evidence for alterations in hippocampal circuit function following single-housing that are associated with deficits in cognitive function and other behaviors associated with depression.