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Synaptic input sequence discrimination on behavioral time-scales mediated by reaction-diffusion chemistry in dendrites

  1. Upinder Singh Bhalla  Is a corresponding author
  1. Tata Institute of Fundamental Research, India
Research Article
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Cite this article as: eLife 2017;6:e25827 doi: 10.7554/eLife.25827


Sequences of events are ubiquitous in sensory, motor, and cognitive function. Key computational operations, including pattern recognition, event prediction, and plasticity, involve neural discrimination of spatio-temporal sequences. Here we show that synaptically-driven reaction-diffusion pathways on dendrites can perform sequence discrimination on behaviorally relevant time-scales. We used abstract signaling models to show that selectivity arises when inputs at successive locations are aligned with, and amplified by, propagating chemical waves triggered by previous inputs. We incorporated biological detail using sequential synaptic input onto spines in morphologically, electrically, and chemically detailed pyramidal neuronal models based on rat data. Again, sequences were recognized, and local channel modulation downstream of putative sequence-triggered signaling could elicit changes in neuronal firing. We predict that dendritic sequence-recognition zones occupy 5 to 30 microns and recognize time-intervals of 0.2 to 5s. We suggest that this mechanism provides highly parallel and selective neural computation in a functionally important time range.

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Author details

  1. Upinder Singh Bhalla

    National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
    For correspondence
    Competing interests
    Upinder Singh Bhalla, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1722-5188


National Centre for Biological Sciences (Plan 4142)

  • Upinder Singh Bhalla

Department of Science and Technology, Ministry of Science and Technology (SR/CSI/66/2013)

  • Upinder Singh Bhalla

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Frances K Skinner, University Health Network, Canada

Publication history

  1. Received: February 7, 2017
  2. Accepted: April 17, 2017
  3. Accepted Manuscript published: April 19, 2017 (version 1)
  4. Accepted Manuscript updated: April 27, 2017 (version 2)
  5. Version of Record published: May 11, 2017 (version 3)


© 2017, Bhalla

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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