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Multiple Running Speed Signals in Medial Entorhinal Cortex.

ABSTRACT: Grid cells in medial entorhinal cortex (MEC) can be modeled using oscillatory interference or attractor dynamic mechanisms that perform path integration, a computation requiring information about running direction and speed. The two classes of computational models often use either an oscillatory frequency or a firing rate that increases as a function of running speed. Yet it is currently not known whether these are two manifestations of the same speed signal or dissociable signals with potentially different anatomical substrates. We examined coding of running speed in MEC and identified these two speed signals to be independent of each other within individual neurons. The medial septum (MS) is strongly linked to locomotor behavior, and removal of MS input resulted in strengthening of the firing rate speed signal, while decreasing the strength of the oscillatory speed signal. Thus, two speed signals are present in MEC that are differentially affected by disrupted MS input.

SUBMITTER: Hinman JR

PROVIDER: S-EPMC4976037 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Multiple Running Speed Signals in Medial Entorhinal Cortex.

Hinman James R JR Brandon Mark P MP Climer Jason R JR Chapman G William GW Hasselmo Michael E ME

Neuron 20160714 3

Grid cells in medial entorhinal cortex (MEC) can be modeled using oscillatory interference or attractor dynamic mechanisms that perform path integration, a computation requiring information about running direction and speed. The two classes of computational models often use either an oscillatory frequency or a firing rate that increases as a function of running speed. Yet it is currently not known whether these are two manifestations of the same speed signal or dissociable signals with potential ...[more]

PMID: 27427460

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