Effects of visual inputs on neural dynamics for coding of location and running speed in medial entorhinal cortex
Abstract
Neuronal representations of spatial location and movement speed in the medial entorhinal cortex during the 'active' theta state of the brain are important for memory-guided navigation and rely on visual inputs. However, little is known about how visual inputs change neural dynamics as a function of running speed and time. By manipulating visual inputs in mice, we demonstrate that changes in spatial stability of grid cell firing correlate with changes in a proposed speed signal by local field potential theta frequency. In contrast, visual inputs do not alter the running speed-dependent gain in neuronal firing rates. Moreover, we provide evidence that sensory inputs other than visual inputs can support grid cell firing, though less accurately, in complete darkness. Finally, changes in spatial accuracy of grid cell firing on a 10 s time scale suggest that grid cell firing is a function of velocity signals integrated over past time.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Matlab code for Figure 4 is provided on the laboratory's GitHub page (https://github.com/hasselmonians/light-modulation and https://github.com/hasselmonians/mle_rhythmicity). Source data files have been provided for Figures 2, 3, 4, 5, and 6.
Article and author information
Author details
Funding
National Institutes of Health (R01MH60013)
- Holger Dannenberg
- Hallie Lazaro
- Pranav Nambiar
- Alec Hoyland
- Michael E. Hasselmo
National Institutes of Health (R01MH120073)
- Holger Dannenberg
- Hallie Lazaro
- Pranav Nambiar
- Alec Hoyland
- Michael E. Hasselmo
National Institutes of Health (R01MH052090)
- Holger Dannenberg
- Hallie Lazaro
- Pranav Nambiar
- Alec Hoyland
- Michael E. Hasselmo
National Institutes of Health (K99NS116129)
- Holger Dannenberg
Office of Naval Research (MURI N00014-16-1-2832)
- Holger Dannenberg
- Hallie Lazaro
- Pranav Nambiar
- Alec Hoyland
- Michael E. Hasselmo
Office of Naval Research (MURI N00014-19-1-2571)
- Holger Dannenberg
- Hallie Lazaro
- Pranav Nambiar
- Alec Hoyland
- Michael E. Hasselmo
Office of Naval Research (DURIP N00014-17-1-2304)
- Holger Dannenberg
- Hallie Lazaro
- Pranav Nambiar
- Alec Hoyland
- Michael E. Hasselmo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All handling of animals and experimental procedures were approved by the Institutional Animal Care and Use Committee (IACUC) for the Charles River Campus at Boston University under protocol #16-008 . All surgery was performed under isoflurane anesthesia and buprenorphine analgesia, and every effort was made to minimize suffering.
Copyright
© 2020, Dannenberg et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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