Competing neural representations of choice shape evidence accumulation in humans
Abstract
Making adaptive choices in dynamic environments requires flexible decision policies. Previously, we showed how the evidence accumulation process that drives decisions shifts when outcome contingencies change (1). Using in silico experiments, here we show how the cortico-basal ganglia-thalamic (CBGT) circuits can feasibly implement shifts in the evidence accumulation process. When action contingencies change, dopaminergic plasticity redirects the balance of power, both within and between action representations, to divert the flow of evidence from one option to another. This model predicts that when competition between action representations is highest, the rate of evidence accumulation is lowest. This prediction was validated in in vivo experiments on human subjects, using fMRI, which showed that 1) evoked hemodynamic responses can reliably predict trialwise choices and 2) competition between action representations, measured using a classifier model, tracked with changes in the rate of evidence accumulation. These results paint a holistic picture of how CBGT circuits manage and adapt the evidence accumulation process in mammals.
Data availability
Behavioral data and computational derivatives are publically available here: https://github.com/kalexandriabond/competing-representations-shape-evidence-accumulation. Raw and preprocessed hemodynamic data, in addition to physiological measurements collected for quality control, are available here: https://openneuro.org/datasets/ds004283/versions/1.0.3.
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neurolokiOpenNeuro; doi:10.18112/openneuro.ds004283.v1.0.3.
Article and author information
Author details
Funding
Air Force Research Laboratory (180119)
- Timothy Verstynen
National Institutes of Health (CRCNS: R01DA053014)
- Timothy Verstynen
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 procedures were approved by the Carnegie Mellon University Institutional Review Board (Approval Code: 2018_00000195).All research participants provided informed consent to participate in the study and consent to publish any research findings based on their provided data.
Copyright
© 2023, Bond 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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