The Dentate Gyrus Classifies Cortical Representations of Learned Stimuli

Nicholas I Woods; Fabio Stefanini; Daniel L Apodaca-Montano; Isabelle M C Tan; Jeremy S Biane; Mazen A Kheirbek

doi:10.1016/j.neuron.2020.04.002

The Dentate Gyrus Classifies Cortical Representations of Learned Stimuli

Neuron. 2020 Jul 8;107(1):173-184.e6. doi: 10.1016/j.neuron.2020.04.002. Epub 2020 Apr 30.

Authors

Nicholas I Woods¹, Fabio Stefanini², Daniel L Apodaca-Montano³, Isabelle M C Tan³, Jeremy S Biane³, Mazen A Kheirbek⁴

Affiliations

¹ Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA; Medical Scientist Training Program, University of California, San Francisco, San Francisco, CA 94158, USA.
² Center for Theoretical Neuroscience, Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, NY 10027, USA.
³ Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94158, USA.
⁴ Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94158, USA; Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA; Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94158, USA; Center for Integrative Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA. Electronic address: [email protected].

Abstract

Animals must discern important stimuli and place them onto their cognitive map of their environment. The neocortex conveys general representations of sensory events to the hippocampus, and the hippocampus is thought to classify and sharpen the distinctions between these events. We recorded populations of dentate gyrus granule cells (DG GCs) and lateral entorhinal cortex (LEC) neurons across days to understand how sensory representations are modified by experience. We found representations of odors in DG GCs that required synaptic input from the LEC. Odor classification accuracy in DG GCs correlated with future behavioral discrimination. In associative learning, DG GCs, more so than LEC neurons, changed their responses to odor stimuli, increasing the distance in neural representations between stimuli, responding more to the conditioned and less to the unconditioned odorant. Thus, with learning, DG GCs amplify the decodability of cortical representations of important stimuli, which may facilitate information storage to guide behavior.

Keywords: 2-photon imaging; dentate gyrus; hippocampus; lateral entorhinal cortex; learning; olfaction.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Animals
Association Learning / physiology*
Dentate Gyrus / physiology*
Male
Mice
Mice, Inbred C57BL
Neurons / physiology*
Olfactory Perception / physiology*

Abstract

Publication types

MeSH terms

Grants and funding