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  1. Article: Prioritizing replay when future goals are unknown.

    Sagiv, Yotam / Akam, Thomas / Witten, Ilana B / Daw, Nathaniel D

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Although hippocampal place cells replay nonlocal trajectories, the computational function of these events remains controversial. One hypothesis, formalized in a prominent reinforcement learning account, holds that replay plans routes to current goals. ... ...

    Abstract Although hippocampal place cells replay nonlocal trajectories, the computational function of these events remains controversial. One hypothesis, formalized in a prominent reinforcement learning account, holds that replay plans routes to current goals. However, recent puzzling data appear to contradict this perspective by showing that replayed destinations lag current goals. These results may support an alternative hypothesis that replay updates route information to build a "cognitive map." Yet no similar theory exists to formalize this view, and it is unclear how such a map is represented or what role replay plays in computing it. We address these gaps by introducing a theory of replay that learns a map of routes to candidate goals, before reward is available or when its location may change. Our work extends the planning account to capture a general map-building function for replay, reconciling it with data, and revealing an unexpected relationship between the seemingly distinct hypotheses.
    Language English
    Publishing date 2024-03-04
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.02.29.582822
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Proactive and reactive construction of memory-based preferences.

    Nicholas, Jonathan / Daw, Nathaniel D / Shohamy, Daphna

    bioRxiv : the preprint server for biology

    2023  

    Abstract: We are often faced with decisions we have never encountered before, requiring us to infer possible outcomes before making a choice. Computational theories suggest that one way to make these types of decisions is by accessing and linking related ... ...

    Abstract We are often faced with decisions we have never encountered before, requiring us to infer possible outcomes before making a choice. Computational theories suggest that one way to make these types of decisions is by accessing and linking related experiences stored in memory. Past work has shown that such memory-based preference construction can occur at a number of different timepoints relative to the moment a decision is made. Some studies have found that memories are integrated at the time a decision is faced (reactively) while others found that memory integration happens earlier, when memories are encoded (proactively). Here we offer a resolution to this inconsistency. We demonstrate behavioral and neural evidence for both strategies and for how they tradeoff rationally depending on the associative structure of memory. Using fMRI to decode patterns of brain responses unique to categories of images in memory, we found that proactive memory access is more common and allows more efficient inference. However, participants also use reactive access when choice options are linked to more numerous memory associations. Together, these results indicate that the brain judiciously conducts proactive inference by accessing memories ahead of time in conditions when this strategy is most favorable.
    Language English
    Publishing date 2023-12-11
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.12.10.570977
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Are we of two minds?

    Daw, Nathaniel D

    Nature neuroscience

    2018  Volume 21, Issue 11, Page(s) 1497–1499

    MeSH term(s) Corpus Striatum ; Uncertainty
    Language English
    Publishing date 2018-10-22
    Publishing country United States
    Document type Journal Article ; Comment
    ZDB-ID 1420596-8
    ISSN 1546-1726 ; 1097-6256
    ISSN (online) 1546-1726
    ISSN 1097-6256
    DOI 10.1038/s41593-018-0258-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Linear reinforcement learning in planning, grid fields, and cognitive control.

    Piray, Payam / Daw, Nathaniel D

    Nature communications

    2021  Volume 12, Issue 1, Page(s) 4942

    Abstract: It is thought that the brain's judicious reuse of previous computation underlies our ability to plan flexibly, but also that inappropriate reuse gives rise to inflexibilities like habits and compulsion. Yet we lack a complete, realistic account of either. ...

    Abstract It is thought that the brain's judicious reuse of previous computation underlies our ability to plan flexibly, but also that inappropriate reuse gives rise to inflexibilities like habits and compulsion. Yet we lack a complete, realistic account of either. Building on control engineering, here we introduce a model for decision making in the brain that reuses a temporally abstracted map of future events to enable biologically-realistic, flexible choice at the expense of specific, quantifiable biases. It replaces the classic nonlinear, model-based optimization with a linear approximation that softly maximizes around (and is weakly biased toward) a default policy. This solution demonstrates connections between seemingly disparate phenomena across behavioral neuroscience, notably flexible replanning with biases and cognitive control. It also provides insight into how the brain can represent maps of long-distance contingencies stably and componentially, as in entorhinal response fields, and exploit them to guide choice even under changing goals.
    MeSH term(s) Brain/physiology ; Cognition ; Decision Making/physiology ; Humans ; Learning/physiology ; Models, Neurological ; Reinforcement, Psychology
    Language English
    Publishing date 2021-08-16
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-021-25123-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Context-sensitive valuation and learning.

    Hunter, Lindsay E / Daw, Nathaniel D

    Current opinion in behavioral sciences

    2021  Volume 41, Page(s) 122–127

    Abstract: A variety of behavioral and neural phenomena suggest that organisms evaluate outcomes not on an absolute utility scale, but relative to some dynamic and context-sensitive reference or scale. Sometimes, as in foraging tasks, this results in sensible ... ...

    Abstract A variety of behavioral and neural phenomena suggest that organisms evaluate outcomes not on an absolute utility scale, but relative to some dynamic and context-sensitive reference or scale. Sometimes, as in foraging tasks, this results in sensible choices; in other situations, like choosing between options learned in different contexts, irrational choices can result. We argue that what unites and demystifies these various phenomena is that the brain's goal is not assessing utility as an end in itself, but rather comparing different options to choose the better one. In the presence of uncertainty, noise, or costly computation, adjusting options to the context can produce more accurate choices.
    Language English
    Publishing date 2021-06-09
    Publishing country Netherlands
    Document type Journal Article
    ISSN 2352-1546
    ISSN 2352-1546
    DOI 10.1016/j.cobeha.2021.05.001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: A model for learning based on the joint estimation of stochasticity and volatility.

    Piray, Payam / Daw, Nathaniel D

    Nature communications

    2021  Volume 12, Issue 1, Page(s) 6587

    Abstract: Previous research has stressed the importance of uncertainty for controlling the speed of learning, and how such control depends on the learner inferring the noise properties of the environment, especially volatility: the speed of change. However, ... ...

    Abstract Previous research has stressed the importance of uncertainty for controlling the speed of learning, and how such control depends on the learner inferring the noise properties of the environment, especially volatility: the speed of change. However, learning rates are jointly determined by the comparison between volatility and a second factor, moment-to-moment stochasticity. Yet much previous research has focused on simplified cases corresponding to estimation of either factor alone. Here, we introduce a learning model, in which both factors are learned simultaneously from experience, and use the model to simulate human and animal data across many seemingly disparate neuroscientific and behavioral phenomena. By considering the full problem of joint estimation, we highlight a set of previously unappreciated issues, arising from the mutual interdependence of inference about volatility and stochasticity. This interdependence complicates and enriches the interpretation of previous results, such as pathological learning in individuals with anxiety and following amygdala damage.
    MeSH term(s) Algorithms ; Animals ; Anxiety ; Anxiety Disorders ; Decision Making ; Haplorhini ; Humans ; Learning/physiology ; Uncertainty ; Volatilization
    Language English
    Publishing date 2021-11-15
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-021-26731-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Dynamic reinforcement learning reveals time-dependent shifts in strategy during reward learning.

    Venditto, Sarah Jo C / Miller, Kevin J / Brody, Carlos D / Daw, Nathaniel D

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Different brain systems have been hypothesized to subserve multiple "experts" that compete to generate behavior. In reinforcement learning, two general processes, one model-free (MF) and one model-based (MB), are often modeled as a mixture of agents (MoA) ...

    Abstract Different brain systems have been hypothesized to subserve multiple "experts" that compete to generate behavior. In reinforcement learning, two general processes, one model-free (MF) and one model-based (MB), are often modeled as a mixture of agents (MoA) and hypothesized to capture differences between automaticity vs. deliberation. However, shifts in strategy cannot be captured by a static MoA. To investigate such dynamics, we present the mixture-of-agents hidden Markov model (MoA-HMM), which simultaneously learns inferred action values from a set of agents and the temporal dynamics of underlying "hidden" states that capture shifts in agent contributions over time. Applying this model to a multi-step,reward-guided task in rats reveals a progression of within-session strategies: a shift from initial MB exploration to MB exploitation, and finally to reduced engagement. The inferred states predict changes in both response time and OFC neural encoding during the task, suggesting that these states are capturing real shifts in dynamics.
    Language English
    Publishing date 2024-03-05
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.02.28.582617
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: An item response theory analysis of the matrix reasoning item bank (MaRs-IB).

    Zorowitz, Samuel / Chierchia, Gabriele / Blakemore, Sarah-Jayne / Daw, Nathaniel D

    Behavior research methods

    2023  Volume 56, Issue 3, Page(s) 1104–1122

    Abstract: Matrix reasoning tasks are among the most widely used measures of cognitive ability in the behavioral sciences, but the lack of matrix reasoning tests in the public domain complicates their use. Here, we present an extensive investigation and ... ...

    Abstract Matrix reasoning tasks are among the most widely used measures of cognitive ability in the behavioral sciences, but the lack of matrix reasoning tests in the public domain complicates their use. Here, we present an extensive investigation and psychometric validation of the matrix reasoning item bank (MaRs-IB), an open-access set of matrix reasoning items. In a first study, we calibrate the psychometric functioning of the items in the MaRs-IB in a large sample of adult participants (N = 1501). Using additive multilevel item structure models, we establish that the MaRs-IB has many desirable psychometric properties: its items span a wide range of difficulty, possess medium-to-large levels of discrimination, and exhibit robust associations between item complexity and difficulty. However, we also find that item clones are not always psychometrically equivalent and cannot be assumed to be exchangeable. In a second study, we demonstrate how experimenters can use the estimated item parameters to design new matrix reasoning tests using optimal item assembly. Specifically, we design and validate two new sets of test forms in an independent sample of adults (N = 600). We find these new tests possess good reliability and convergent validity with an established measure of matrix reasoning. We hope that the materials and results made available here will encourage experimenters to use the MaRs-IB in their research.
    MeSH term(s) Adult ; Humans ; Reproducibility of Results ; Problem Solving ; Cognition ; Psychometrics ; Surveys and Questionnaires
    Language English
    Publishing date 2023-04-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 231560-9
    ISSN 1554-3528 ; 0743-3808 ; 1554-351X
    ISSN (online) 1554-3528
    ISSN 0743-3808 ; 1554-351X
    DOI 10.3758/s13428-023-02067-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Uncertainty alters the balance between incremental learning and episodic memory.

    Nicholas, Jonathan / Daw, Nathaniel D / Shohamy, Daphna

    eLife

    2022  Volume 11

    Abstract: A key question in decision making is how humans arbitrate between competing learning and memory systems to maximize reward. We address this question by probing the balance between the effects, on choice, of incremental trial-and-error learning versus ... ...

    Abstract A key question in decision making is how humans arbitrate between competing learning and memory systems to maximize reward. We address this question by probing the balance between the effects, on choice, of incremental trial-and-error learning versus episodic memories of individual events. Although a rich literature has studied incremental learning in isolation, the role of episodic memory in decision making has only recently drawn focus, and little research disentangles their separate contributions. We hypothesized that the brain arbitrates rationally between these two systems, relying on each in circumstances to which it is most suited, as indicated by uncertainty. We tested this hypothesis by directly contrasting contributions of episodic and incremental influence to decisions, while manipulating the relative uncertainty of incremental learning using a well-established manipulation of reward volatility. Across two large, independent samples of young adults, participants traded these influences off rationally, depending more on episodic information when incremental summaries were more uncertain. These results support the proposal that the brain optimizes the balance between different forms of learning and memory according to their relative uncertainties and elucidate the circumstances under which episodic memory informs decisions.
    Language English
    Publishing date 2022-12-02
    Publishing country England
    Document type Journal Article
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.81679
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: A simple model for learning in volatile environments.

    Piray, Payam / Daw, Nathaniel D

    PLoS computational biology

    2020  Volume 16, Issue 7, Page(s) e1007963

    Abstract: Sound principles of statistical inference dictate that uncertainty shapes learning. In this work, we revisit the question of learning in volatile environments, in which both the first and second-order statistics of observations dynamically evolve over ... ...

    Abstract Sound principles of statistical inference dictate that uncertainty shapes learning. In this work, we revisit the question of learning in volatile environments, in which both the first and second-order statistics of observations dynamically evolve over time. We propose a new model, the volatile Kalman filter (VKF), which is based on a tractable state-space model of uncertainty and extends the Kalman filter algorithm to volatile environments. The proposed model is algorithmically simple and encompasses the Kalman filter as a special case. Specifically, in addition to the error-correcting rule of Kalman filter for learning observations, the VKF learns volatility according to a second error-correcting rule. These dual updates echo and contextualize classical psychological models of learning, in particular hybrid accounts of Pearce-Hall and Rescorla-Wagner. At the computational level, compared with existing models, the VKF gives up some flexibility in the generative model to enable a more faithful approximation to exact inference. When fit to empirical data, the VKF is better behaved than alternatives and better captures human choice data in two independent datasets of probabilistic learning tasks. The proposed model provides a coherent account of learning in stable or volatile environments and has implications for decision neuroscience research.
    MeSH term(s) Algorithms ; Computer Simulation ; Humans ; Learning/physiology ; Models, Psychological ; Signal Processing, Computer-Assisted ; Task Performance and Analysis
    Language English
    Publishing date 2020-07-01
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1007963
    Database MEDical Literature Analysis and Retrieval System OnLINE

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