Organization of cell assemblies in the hippocampus

  title={Organization of cell assemblies in the hippocampus},
  author={Kenneth D. Harris and Jozsef Csicsvari and Hajime Hirase and George Dragoi and Gy{\"o}rgy Buzs{\'a}ki},
Neurons can produce action potentials with high temporal precision. A fundamental issue is whether, and how, this capability is used in information processing. According to the ‘cell assembly’ hypothesis, transient synchrony of anatomically distributed groups of neurons underlies processing of both external sensory input and internal cognitive mechanisms. Accordingly, neuron populations should be arranged into groups whose synchrony exceeds that predicted by common modulation by sensory input… 

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These results demonstrate that distinct processing states arise from the engagement of rhythmically identifiable circuits, which have unique roles in organizing task-relevant processing in the hippocampus.

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Dual Coding with STDP in a Spiking Recurrent Neural Network Model of the Hippocampus

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Synchronization and assembly formation in the visual cortex.

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It is suggested that intrinsic properties of pyramidal cells have a key role in determining spike times, and that the interplay between the magnitude of dendritic excitation and rhythmic inhibition of the somatic region is responsible for the phase assignment of spikes.

Role of experience and oscillations in transforming a rate code into a temporal code

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Theta phase precession in hippocampal neuronal populations and the compression of temporal sequences

Large‐scale parallel recordings are made use of to clarify and extend the finding that a cell's spike activity advances to earlier phases of the theta cycle as the rat passes through the cell's place field, and to show Granule cells of the fascia dentata are also modulated by theta.

Oscillatory Coupling of Hippocampal Pyramidal Cells and Interneurons in the Behaving Rat

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The global record of memory in hippocampal neuronal activity

Training rats to perform the same recognition memory task in several distinct locations in a rich spatial environment found that the activity of many hippocampal neurons was related consistently to perceptual, behavioural or cognitive events, regardless of the location where these events occurred, indicating that non-spatial events are fundamental elements of hippocampal representation.

Dynamics of the hippocampal ensemble code for space.

Parallel recording methods outlined here make possible the study of the dynamics of neuronal interactions during unique behavioral events, which suggests that new spatial information creates conditions in the hippocampal circuitry that are conducive to the synaptic modification presumed to be involved in learning.

Phase relationship between hippocampal place units and the EEG theta rhythm

The phase was highly correlated with spatial location and less well correlated with temporal aspects of behavior, such as the time after place field entry, and the characteristics of the phase shift constrain the models that define the construction of place fields.

Independence of Firing Correlates of Anatomically Proximate Hippocampal Pyramidal Cells

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