SPEAKER: Dr. May-Britt Moser
ORGANIZATION: Kavli Institute for Systems Neuroscience
DATE + TIME: Wednesday February 5, 2014 at 4pm
LOCATION: MIT Bldg 46-3002 (Singleton Auditorium)
ABSTRACT: The medial entorhinal cortex (MEC) is part of the brain’s circuit for dynamic representation of self-location. The metric of this representation is provided by grid cells, cells with spatial firing fields that tile environments in a periodic hexagonal pattern. I will begin my lecture by discussing how grid cells are organized within the MEC. Based on recordings from large numbers of grid cells in individual rats, I will show that grid cells cluster into a small number of layer-spanning anatomically-overlapping functionally independent modules with distinct scale and orientation – a property that may be advantage to high-capacity memory in output areas such as the hippocampus. I will further discuss how inputs from grid cells and other functional cell types determine properties of place cells in the hippocampus. Using a combination of electrophysiological and optogenetic techniques, we find that the hippocampus receives input from a variety of sources, including border cells and head direction cells in the MEC, odour-responsive cells in the lateral entorhinal cortex, and, via the nucleus reuniens, decision-correlated cells in the medial prefrontal cortex. Collectively these inputs may be enable memory in ensembles of place cells in the hippocampus.