The Colgin lab has published a paper in the journal Hippocampus entitled “The Relationship Between Gamma Frequency and Running Speed Differs for Slow and Fast Gamma Rhythms in Freely Behaving Rats”. This research investigates the way that different subtypes of gamma rhythms in the hippocampus correlate differently with rats’ behavior. Specifically, the frequency of fast gamma rhythms increases with increasing running speeds, whereas the frequency of slow gamma rhythms does not change much with running speed. Increasing fast gamma frequencies likely allow for more rapid transitions across place cell assemblies that represent sequences of locations, as the animal moves more quickly through those locations. During slow gamma states, place cell representations are not as strongly linked to ongoing behavior and may instead reflect other functions, such as planning of future routes.
Zheng C, Bieri KW, Trettel SG, and Colgin LL. 2015. The Relationship Between Gamma Frequency and Running Speed Differs for Slow and Fast Gamma Rhythms in Freely Behaving Rats. Hippocampus. Epub ahead of print.