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Neural signatures of cell assembly organization

Nature Reviews Neuroscience volume 6, pages 399–407 (2005)Cite this article

Abstract

Cortical neurons show irregular but structured spike trains. This has been interpreted as evidence for 'temporal coding', whereby stimuli are represented by precise spike-timing patterns. Here, we suggest an alternative interpretation based on the older concept of the cell assembly. The dynamic evolution of assembly sequences, which are steered but not deterministically controlled by sensory input, is the proposed substrate of psychological processes beyond simple stimulus–response associations. Accordingly, spike trains show a temporal structure that is stimulus-dependent and more variable than would be predicted by strict sensory control. We propose four signatures of assembly organization that can be experimentally tested. We argue that many observations that have been interpreted as evidence for temporal coding might instead reflect an underlying assembly structure.

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Figure 1: The cell assembly hypothesis.
Figure 2: Assembly structure analysis.
Figure 3: Spike timing of hippocampal neurons.
Figure 4: Peer prediction analysis of assembly organization in the hippocampus.
Figure 5: Stimulus reconstruction and peer prediction paradigms.
Figure 6: Timescales of synchronization.

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Acknowledgements

I thank G. Buzsaki, S. Montgomery and E. Ludvig for comments on the manuscript. K.D.H. is supported by NIH and an Alfred P. Sloan research fellowship.

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  1. the Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, 197 University Avenue, Newark, 07102, New Jersey, USA

    Kenneth D. Harris

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Harris, K. Neural signatures of cell assembly organization. Nat Rev Neurosci 6, 399–407 (2005). https://doi.org/10.1038/nrn1669

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