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Updated: Jun 21, 2026
10:59
Investigations on Alterations of Hippocampal Circuit Function Following Mild Traumatic Brain Injury
Published on: November 19, 2012
A phase code for memory could arise from circuit mechanisms in entorhinal cortex
Michael E Hasselmo1, Mark P Brandon, Motoharu Yoshida
1Center for Memory and Brain, Department of Psychology and Program in Neuroscience, Boston University, 2 Cummington Street, Boston, MA 02215, USA. hasselmo@bu.edu
Summary
Entorhinal cortical neurons may encode memory through their firing phase. This mechanism could explain grid cell activity and neural replay during rest and sleep.
Area of Science:
- Neuroscience
- Computational Neuroscience
Background:
- Entorhinal cortex (EC) neurons play a crucial role in memory formation and spatial navigation.
- Intrinsic cellular properties of neurons are fundamental to understanding neural coding.
Purpose of the Study:
- To explore how intrinsic cellular properties of entorhinal cortical neurons facilitate memory coding via firing phase.
- To review potential cellular mechanisms for phase coding in computational models of entorhinal function.
Main Methods:
- Review of neurophysiological data and computational models of entorhinal cortex function.
- Analysis of cellular mechanisms underlying neural firing phase.
- Discussion of implications for modeling grid cell responses and neural replay.
Main Results:
- Intrinsic cellular properties suggest a mechanism for entorhinal cortical neurons to code memory by firing phase.
- Phase coding provides a basis for modeling entorhinal grid cell responses.
- This mechanism supports modeling of neural spiking activity replay during waking and sleep.
Conclusions:
- Phase coding by entorhinal cortical neurons offers a plausible mechanism for memory representation.
- Further research in biophysical simulations and large-scale population models is warranted to explore inhibition's role.
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