Research Meeting: Hippocampal Remapping as Learned Clustering of Experiences (Honi Sanders)

February 6, 2019 - 4:00 pm
Speaker/s: 

Honi Sanders (Wilson + Gershman labs)

Organizer: 

The place cells of the hippocampus create distinct maps of each context, a process known as hippocampal remapping.  Past work has asked which environmental features determine which map is used, but no consistent answer has been reached. However, this approach has ignored the relevance of context identification as part of a larger learning process. 

In order to address the question of which features determine which map is used, we must explicitly raise some of the complexities that make the context learning problem an intrinsically difficult problem.  The brain does not know a priori what features of the environment will be relevant, nor does it have direct access to context identity labels.  Fundamentally, this corresponds to an unsupervised clustering problem, where the brain receives a stream of experiences and must cluster them in a data-driven manner. 

Our results emphasize that learning plays a large role in hippocampal remapping.  Formalizing context learning as a clustering problems allows us to capture a range of experimental results that have not yet been explained by a single theoretical framework.  This model also provides novel predictions including the effect of variability in training as well as providing novel analyses including characterizing animal-to-animal variability. 

Details

Date: 
February 6, 2019
Time: 
4:00 pm
Venue: 
MIT 46-6011
Address: 

MIT Bldg 46, Rm 6011

43 Vassar St, Cambridge MA 02139