Multiple decisions about one object involve parallel sensory acquisition but time-multiplexed evidence incorporation
Abstract
The brain is capable of processing several streams of information that bear on different aspects of the same problem. Here we address the problem of making two decisions about one object, by studying difficult perceptual decisions about the color and motion of a dynamic random dot display. We find that the accuracy of one decision is unaffected by the difficulty of the other decision. However, the response times reveal that the two decisions do not form simultaneously. We show that both stimulus dimensions are acquired in parallel for the initial ∼0.1 s but are then incorporated serially in time-multiplexed bouts. Thus there is a bottleneck that precludes updating more than one decision at a time, and a buffer that stores samples of evidence while access to the decision is blocked. We suggest that this bottleneck is responsible for the long timescales of many cognitive operations framed as decisions.
Data availability
The data is on figshare at: https://dx.doi.org/10.6084/m9.figshare.13607255The code is available at the following repository: https://github.com/yulkang/2D_DecisionThe figshare (allows deposition of big data) and github (suitable for maintenance of code) repositories refer to each other.
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Data for "Multiple decisions about one object involve parallel sensory acquisition but time-multiplexed evidence incorporation"Figshare, doi:10.6084/m9.figshare.13607255.
Article and author information
Author details
Funding
National Eye Institute (T32EY01393)
- Yul HR Kang
Simons Foundation (414196)
- Danique Jeurissen
Brain and Behavior Research Foundation (28476)
- Danique Jeurissen
Howard Hughes Medical Institute
- Michael N Shadlen
National Eye Institute (R01EY11378)
- Michael N Shadlen
National Institute of Neurological Disorders and Stroke (R01NS113113)
- Michael N Shadlen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The study was approved by the local ethics committee (Institutional Review Board of Columbia University Medical Center IRB-AAAL0658 & IRB-AAAR9148 ). Thirteen participants (5 male and 8 female, age 23-40, median = 26, IQR = 25-32, mean = 28.3, SD = 5.74) provided written informed consent and took part in the study
Reviewing Editor
- Kristine Krug, University of Oxford, United Kingdom
Version history
- Received: October 4, 2020
- Accepted: March 6, 2021
- Accepted Manuscript published: March 10, 2021 (version 1)
- Version of Record published: May 11, 2021 (version 2)
Copyright
© 2021, Kang et al.
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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