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Linking cellular mechanisms to behavior: entorhinal persistent spiking and membrane potential oscillations may underlie path integration, grid cell firing, and episodic memory.

Hasselmo ME, Brandon MP - Neural Plast. (2008)

Bottom Line: The entorhinal cortex plays an important role in spatial memory and episodic memory functions.This article reviews physiological data on persistent spiking and membrane potential oscillations in entorhinal cortex then presents models showing how both these cellular mechanisms could contribute to properties observed during unit recording, including grid cell firing, and how they could underlie behavioural functions including path integration.The interaction of oscillations and persistent firing could contribute to encoding and retrieval of trajectories through space and time as a mechanism relevant to episodic memory.

View Article: PubMed Central - PubMed

Affiliation: Center for Memory and Brain, Department of Psychology and Program in Neuroscience, Boston University, 2 Cummington Sreet, Boston, MA 02215, USA. hasselmo@bu.edu

ABSTRACT
The entorhinal cortex plays an important role in spatial memory and episodic memory functions. These functions may result from cellular mechanisms for integration of the afferent input to entorhinal cortex. This article reviews physiological data on persistent spiking and membrane potential oscillations in entorhinal cortex then presents models showing how both these cellular mechanisms could contribute to properties observed during unit recording, including grid cell firing, and how they could underlie behavioural functions including path integration. The interaction of oscillations and persistent firing could contribute to encoding and retrieval of trajectories through space and time as a mechanism relevant to episodic memory.

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Related in: MedlinePlus

Simulation of theta phase precession in grid cell model based onmembrane potential oscillations.  (a)Theta phase plotted on vertical axis as a simulated rat runs through a gridcell firing field in west to east and east to west directions.  (b) Theta phase during run from south tonorth.  (c) Spike times (filled circles)of summed oscillations in a neuron relative to oscillation in the soma of thatneuron (negative of network theta oscillation).
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fig4: Simulation of theta phase precession in grid cell model based onmembrane potential oscillations. (a)Theta phase plotted on vertical axis as a simulated rat runs through a gridcell firing field in west to east and east to west directions. (b) Theta phase during run from south tonorth. (c) Spike times (filled circles)of summed oscillations in a neuron relative to oscillation in the soma of thatneuron (negative of network theta oscillation).

Mentions: Plotting of theta phase precessionessentially involves plotting the timing of spikes (which occur when φsum = n2π) relative to the phase of the networkoscillations (which here correspond to the phase of the soma because the somais being driven by network oscillations with fixed frequency ω). Thus, the vertical axis of a plot of thetaphase precession shows the phase of the soma oscillation at the time of eachspike: φsoma = n2π − π f Bx plotted relative to location x on thehorizontal axis. Figure 4 shows theplotting of spikes in the simulation during runs on a linear track through thefiring field of the neuron. Note thatthe phase precession in this model resembles the phase precession found in experimental data [50] but only covers about 180 degrees of the network theta oscillationcycle.


Linking cellular mechanisms to behavior: entorhinal persistent spiking and membrane potential oscillations may underlie path integration, grid cell firing, and episodic memory.

Hasselmo ME, Brandon MP - Neural Plast. (2008)

Simulation of theta phase precession in grid cell model based onmembrane potential oscillations.  (a)Theta phase plotted on vertical axis as a simulated rat runs through a gridcell firing field in west to east and east to west directions.  (b) Theta phase during run from south tonorth.  (c) Spike times (filled circles)of summed oscillations in a neuron relative to oscillation in the soma of thatneuron (negative of network theta oscillation).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2480478&req=5

fig4: Simulation of theta phase precession in grid cell model based onmembrane potential oscillations. (a)Theta phase plotted on vertical axis as a simulated rat runs through a gridcell firing field in west to east and east to west directions. (b) Theta phase during run from south tonorth. (c) Spike times (filled circles)of summed oscillations in a neuron relative to oscillation in the soma of thatneuron (negative of network theta oscillation).
Mentions: Plotting of theta phase precessionessentially involves plotting the timing of spikes (which occur when φsum = n2π) relative to the phase of the networkoscillations (which here correspond to the phase of the soma because the somais being driven by network oscillations with fixed frequency ω). Thus, the vertical axis of a plot of thetaphase precession shows the phase of the soma oscillation at the time of eachspike: φsoma = n2π − π f Bx plotted relative to location x on thehorizontal axis. Figure 4 shows theplotting of spikes in the simulation during runs on a linear track through thefiring field of the neuron. Note thatthe phase precession in this model resembles the phase precession found in experimental data [50] but only covers about 180 degrees of the network theta oscillationcycle.

Bottom Line: The entorhinal cortex plays an important role in spatial memory and episodic memory functions.This article reviews physiological data on persistent spiking and membrane potential oscillations in entorhinal cortex then presents models showing how both these cellular mechanisms could contribute to properties observed during unit recording, including grid cell firing, and how they could underlie behavioural functions including path integration.The interaction of oscillations and persistent firing could contribute to encoding and retrieval of trajectories through space and time as a mechanism relevant to episodic memory.

View Article: PubMed Central - PubMed

Affiliation: Center for Memory and Brain, Department of Psychology and Program in Neuroscience, Boston University, 2 Cummington Sreet, Boston, MA 02215, USA. hasselmo@bu.edu

ABSTRACT
The entorhinal cortex plays an important role in spatial memory and episodic memory functions. These functions may result from cellular mechanisms for integration of the afferent input to entorhinal cortex. This article reviews physiological data on persistent spiking and membrane potential oscillations in entorhinal cortex then presents models showing how both these cellular mechanisms could contribute to properties observed during unit recording, including grid cell firing, and how they could underlie behavioural functions including path integration. The interaction of oscillations and persistent firing could contribute to encoding and retrieval of trajectories through space and time as a mechanism relevant to episodic memory.

Show MeSH
Related in: MedlinePlus