One-shot learning and behavioral eligibility traces in sequential decision making
Abstract
In many daily tasks we make multiple decisions before reaching a goal. In order to learn such sequences of decisions, a mechanism to link earlier actions to later reward is necessary. Reinforcement learning theory suggests two classes of algorithms solving this credit assignment problem: In classic temporal-difference learning, earlier actions receive reward information only after multiple repetitions of the task, whereas models with eligibility traces reinforce entire sequences of actions from a single experience (one-shot). Here we show one-shot learning of sequences. We developed a novel paradigm to directly observe which actions and states along a multi-step sequence are reinforced after a single reward. By focusing our analysis on those states for which RL with and without eligibility trace make qualitatively distinct predictions, we find direct behavioral (choice probability) and physiological (pupil dilation) signatures of reinforcement learning with eligibility trace across multiple sensory modalities.
Data availability
The datasets generated during the current study are available on Dryad, at the following address https://dx.doi.org/10.5061/dryad.j7h6f69
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Data from: One-shot learning and behavioral eligibility traces in sequential decision makingDryad Digital Repository, doi:10.5061/dryad.j7h6f69.
Article and author information
Author details
Funding
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (CRSII2 147636 (Sinergia))
- Marco P Lehmann
- He A Xu
- Vasiliki Liakoni
- Michael H Herzog
- Wulfram Gerstner
- Kerstin Preuschoff
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (CRSII2 200020 165538)
- Marco P Lehmann
- Vasiliki Liakoni
- Wulfram Gerstner
Horizon 2020 Framework Programme (Human Brain Project (SGA2) 785907)
- Michael H Herzog
- Wulfram Gerstner
H2020 European Research Council (268 689 MultiRules)
- Wulfram Gerstner
Horizon 2020 Framework Programme (Human Brain Project (SGA1) 720270)
- Michael H Herzog
- Wulfram Gerstner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Experiments were conducted in accordance with the Helsinki declaration and approved by the ethics commission of the Canton de Vaud (164/14 Titre: Aspects fondamentaux de la reconnaissance des objets : protocole général). All participants were informed about the general purpose of the experiment and provided written, informed consent. They were told that they could quit the experiment at any time they wish.
Copyright
© 2019, Lehmann 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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