1. Neuroscience
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Sequential sensory and decision processing in posterior parietal cortex

  1. Guilhem Ibos  Is a corresponding author
  2. David J Freedman
  1. The University of Chicago, United States
Research Article
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Cite this article as: eLife 2017;6:e23743 doi: 10.7554/eLife.23743


Decisions about the behavioral significance of sensory stimuli often require comparing sensory inference of what we are looking at to internal models of what we are looking for. Here, we test how neuronal selectivity for visual features is transformed into decision-related signals in posterior parietal cortex (area LIP). Monkeys performed a visual matching task that required them to detect target stimuli composed of conjunctions of color and motion-direction. Neuronal recordings from area LIP revealed two main findings. First, the sequential processing of visual features and the selection of target-stimuli suggest that LIP is involved in transforming sensory information into decision-related signals. Second, the patterns of color and motion selectivity and their impact on decision-related encoding suggest that LIP plays a role in detecting target stimuli by comparing bottom-up sensory inputs (what the monkeys were looking at) and top-down cognitive encoding inputs (what the monkeys were looking for).

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Author details

  1. Guilhem Ibos

    Department of Neurobiology, The University of Chicago, Chicago, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9280-1280
  2. David J Freedman

    Department of Neurobiology, The University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2485-5981


National Institutes of Health (R01 EY019041)

  • David J Freedman

National Science Foundation (955640)

  • David J Freedman

McKnight Endowment Fund for Neuroscience

  • David J Freedman

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


Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All experimental procedures were in accordance with the University of Chicago Animal Care and Use Committee (IACUC), protocol #71887, of the University of Chicago and National Institutes of Health guidelines.

Reviewing Editor

  1. Tatiana Pasternak, University of Rochester, United States

Publication history

  1. Received: November 29, 2016
  2. Accepted: April 16, 2017
  3. Accepted Manuscript published: April 18, 2017 (version 1)
  4. Accepted Manuscript updated: April 24, 2017 (version 2)
  5. Version of Record published: May 8, 2017 (version 3)


© 2017, Ibos & Freedman

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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