Date of Completion

Spring 5-1-2016

Thesis Advisor(s)

Etan Markus

Honors Major

Physiology and Neurobiology


Behavioral Neurobiology


The hippocampus is a region of the brain which plays a major role in encoding spatial and episodic memory. The hippocampus is divided in to two main subregions, dorsal and ventral. These subregions are connected, but their functional organization remains widely unknown. Place cells are cells of the hippocampus which fire in a specific spatial area and help create a mental map of our surroundings. Place cells have been seen to remain constant during slight fluctuations in surroundings, but completely remap in response to large fluctuations in the environment. There is little known about the relatively few place cells in the ventral hippocampus. This project used single unit electrodes to record from one place cell at a time over several weeks. The electrode recorded each time the place cell fired, and this data was compared to behavioral data. The electrode was moved each recording day to record from place cells in both the dorsal and ventral hippocampus allowing us to shed light on the connectivity of the dorsal and ventral hippocampus. My work focused on analyzing the exact placement of the single unit electrode on each recording day. This work was done by using the electrode track to calculate the location of the electrode on prior days. In order to find the electrode track the animal was sacrificed and its brain was extracted, sliced, stained, and imaged. The staining and imaging allowed us to visualize the location of the electrode on previous recording days.