1. Neuroscience

The representational dynamics of task and object processing in humans

  1. Martin N Hebart  Is a corresponding author
  2. Brett B Bankson
  3. Assaf Harel
  4. Chris I Baker
  5. Radoslaw M Cichy
  1. National Institute of Mental Health, United States
  2. Wright State University, United States
  3. Free University of Berlin, Germany
https://doi.org/10.7554/eLife.32816
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  1. Martin N Hebart
  2. Brett B Bankson
  3. Assaf Harel
  4. Chris I Baker
  5. Radoslaw M Cichy
(2018)
The representational dynamics of task and object processing in humans
eLife 7:e32816.
https://doi.org/10.7554/eLife.32816
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Abstract

Despite the importance of an observer's goals in determining how a visual object is categorized, surprisingly little is known about how humans process the task context in which objects occur and how it may interact with the processing of objects. Using magnetoencephalography (MEG), functional magnetic resonance imaging (fMRI) and multivariate techniques, we studied the spatial and temporal dynamics of task and object processing. Our results reveal a sequence of separate but overlapping task-related processes spread across frontoparietal and occipitotemporal cortex. Task exhibited late effects on object processing by selectively enhancing task-relevant object features, with limited impact on the overall pattern of object representations. Combining MEG and fMRI data, we reveal a parallel rise in task-related signals throughout the cerebral cortex, with an increasing dominance of task over object representations from early to higher visual areas. Collectively, our results reveal the complex dynamics underlying task and object representations throughout human cortex.

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Author details

  1. Martin N Hebart

    Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, United States
    For correspondence
    martin.hebart@nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7257-428X

  2. Brett B Bankson

    Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7663-3918

  3. Assaf Harel

    Department of Psychology, Wright State University, Dayton, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Chris I Baker

    Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6861-8964

  5. Radoslaw M Cichy

    Department of Education and Psychology, Free University of Berlin, Berlin, Germany
    Competing interests
    The authors declare that no competing interests exist.

Funding

National Institutes of Health

  • Martin N Hebart
  • Brett B Bankson
  • Chris I Baker

Deutsche Forschungsgemeinschaft

  • Radoslaw M Cichy

Alexander von Humboldt-Stiftung

  • Martin N Hebart

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

Ethics

Human subjects: All participants gave written informed consent as part of the study protocol (93-M-0170, NCT00001360) prior to participation in the study. The study was approved by the Institutional Review Board of the National Institutes of Health and was conducted according to the Declaration of Helsinki.

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Martin N Hebart
  2. Brett B Bankson
  3. Assaf Harel
  4. Chris I Baker
  5. Radoslaw M Cichy
(2018)
The representational dynamics of task and object processing in humans
eLife 7:e32816.
https://doi.org/10.7554/eLife.32816

Share this article

https://doi.org/10.7554/eLife.32816

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