Exploration of the Propagation of Hippocampal Theta Oscillations in Freely Moving Rats

Abstract

Comprehending the mechanisms by which theta waves propagate across the hippocampus is of utmost importance in understanding various aspects of cognition in rodent models. A popular argument made by those studying hippocampal rhythms is that they are synchronous throughout the medial temporal lobe. However, recent studies have concluded that theta oscillations travel as waves along the septotemporal axis of the hippocampus. Our experimental goal was to derive a relationship between theta oscillations in the anterior and posterior regions of the hippocampus by examining local field potential in freely moving rats. We trained a mixed-sex cohort of five Fisher Brown Norway hybrid rats to run on a circular track for a food reward and implanted them with an intracranial silicon probe in the CA1 region of the anterior dorsal hippocampus (AP: -2.8 ML: 1.5 DV: 4.0) and the CA1 region of the posterior parietal hippocampus (AP: -5.6 ML: 4.2 DV: 4.5). After a recovery period, the rats were reintroduced to the circular track where data was collected from each site. This poster presents the activity of traveling dentate spikes, ripples, theta, and gamma within these hippocampal regions. R01MH126236 1R01MH109548-01A1. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.