Tracking subjects' strategies in behavioural choice experiments at trial resolution
Abstract
Investigating how, when, and what subjects learn during decision-making tasks requires tracking their choice strategies on a trial-by-trial basis. Here we present a simple but effective probabilistic approach to tracking choice strategies at trial resolution using Bayesian evidence accumulation. We show this approach identifies both successful learning and the exploratory strategies used in decision tasks performed by humans, non-human primates, rats, and synthetic agents. Both when subjects learn and when rules change the exploratory strategies of win-stay and lose-shift, often considered complementary, are consistently used independently. Indeed, we find the use of lose-shift is strong evidence that subjects have latently learnt the salient features of a new rewarded rule. Our approach can be extended to any discrete choice strategy, and its low computational cost is ideally suited for real-time analysis and closed-loop control.
Data availability
Source data from the rat Y-maze task data are available from crcns.org at http://dx.doi.org/10.6080/K0KH0KH5. Source data from the rat lever-press task (32 rats), the human gain/loss task (20 participants) and the primate stimulus-to-action task (one session) are available from the Nottingham Research Data Management Service at http://doi.org/10.17639/nott.7274.Processed data and analysis code to replicate all figures are available in our GitHub repository https://github.com/Humphries-Lab/Bayesian_strategy_analysis_Paper. Our copies of the source data for the Y-maze task, lever-press task, gain/loss task, and stimulus-to-action task are also freely available from the same repository.
Article and author information
Author details
Funding
Medical Research Council (MR/J008648/1)
- Mark D Humphries
Medical Research Council (MR/P005659/1)
- Mark D Humphries
Medical Research Council (MR/S025944/1)
- Mark D Humphries
Medical Research Council (MR/K005480/1)
- Mark Buckley
Biotechnology and Biological Sciences Research Council (BB/T00598X/1)
- Mark Buckley
- Mark D Humphries
Biotechnology and Biological Sciences Research Council (BB/M008770/1)
- Rebecca M Hock
- Paula M Moran
- Tobias Bast
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Rat - lever-press task: All experimental procedures were conducted in accordance with the requirements of the United Kingdom (UK) Animals (Scientific Procedures) Act 1986, approved by the University of Nottingham's Animal Welfare and Ethical Review Board (AWERB) and run under the authority of Home Office project license 30/3357.Non-human primate task: All animal training and experimental procedures were performed in accordance with the guidelines of the UK Animals (Scientific Procedures) Act of 1986, licensed by the UK Home Office, and approved by Oxford University's Committee on Animal Care and Ethical Review.
Human subjects: The human gain/loss task study was approved by Research Ethics Committee (Stanmore London REC 17/LO/0577). All participants were read a participation information leaflet and undertook informed consent.
Copyright
© 2024, Maggi 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.