Strategy-dependent effects of working-memory limitations on human perceptual decision-making
Abstract
Deliberative decisions based on an accumulation of evidence over time depend on working memory, and working memory has limitations, but how these limitations affect deliberative decision-making is not understood. We used human psychophysics to assess the impact of working-memory limitations on the fidelity of a continuous decision variable. Participants decided the average location of multiple visual targets. This computed, continuous decision variable degraded with time and capacity in a manner that depended critically on the strategy used to form the decision variable. This dependence reflected whether the decision variable was computed either: 1) immediately upon observing the evidence, and thus stored as a single value in memory; or 2) at the time of the report, and thus stored as multiple values in memory. These results provide important constraints on how the brain computes and maintains temporally dynamic decision variables.
Data availability
All analysis code is available on GitHub (https://github.com/TheGoldLab/Memory_Diffusion_Task). Data used for figures will be made available on Dryad.
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Memory Diffusion Task DataDryad Digital Repository, doi:10.5061/dryad.w3r2280rm.
Article and author information
Author details
Funding
National Institute of Mental Health (R01 MH115557)
- Kresimir Josic
- Zachary P Kilpatrick
- Joshua I Gold
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 task was created with PsychoPy3 and distributed to participants via Pavlovia.com, which allowed participants to perform the task on their home computers after providing informed consent. These protocols were reviewed by the University of Pennsylvania Institutional Review Board (IRB) and determined to meet eligibility criteria for IRB review exemption authorized by 45 CFR 46.104, category 2.
Copyright
© 2022, Schapiro 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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