Differentiating between integration and non-integration strategies in perceptual decision making
Abstract
Many tasks used to study decision-making encourage subjects to integrate evidence over time. Such tasks are useful to understand how the brain operates on multiple samples of information over prolonged timescales, but only if subjects actually integrate evidence to form their decisions. We explored the behavioral observations that corroborate evidence-integration in a number of task-designs. Several commonly accepted signs of integration were also predicted by non-integration strategies. Furthermore, an integration model could fit data generated by non-integration models. We identified the features of non-integration models that allowed them to mimic integration and used these insights to design a motion discrimination task that disentangled the models. In human subjects performing the task, we falsified a non-integration strategy in each and confirmed prolonged integration in all but one subject. The findings illustrate the difficulty of identifying a decision-maker's strategy and support solutions to achieve this goal.
Data availability
The data generated during this study are included in the source data file for Figure 6.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Ariel Zylberberg
- Michael N Shadlen
National Eye Institute (EY011378)
- Gabriel M Stine
- Ariel Zylberberg
- Michael N Shadlen
National Eye Institute (EY013933)
- Gabriel M Stine
National Institute of Neurological Disorders and Stroke (NS113113)
- Gabriel M Stine
- Ariel Zylberberg
- Michael N Shadlen
Israel Institute for Advanced Studies
- 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: Human subjects: The institutional review board of Columbia University (protocol #IRB-AAAL0658) approved the experimental protocol, and subjects gave written informed consent.
Copyright
© 2020, Stine 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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