{ "abstract": "The successor representation (SR) is a reinforcement learning strategy which has been suggested to underlie nuanced forms of habitual behavior, rendering it a candidate mechanism for mental health conditions thought to involve habitual control, such as addiction. However, paradigms used to assess habits in humans cannot detect SR use. Together with the fact that they are usually conducted in disorder-irrelevant contexts, this may explain why the evidence for a hypothesized shift from goal-directed to habitual behavior in addiction is inconsistent. Here, we tested whether individuals with high-risk (n = 260) compared to low-risk drinking behavior (n = 260) rely more on SR or a rigid goal-based dimension-reduced SR variant (redSR), particularly in alcohol-related contexts. An online multi-stage decision-making task performed in either a virtual bar or apartment context allowed us to dissociate (red)SR from model-based and model-free learning strategies by testing how well participants adapted their choices to different types of distal changes in the environment. Findings suggest that a particular type of SR, namely a (reduced) random-policy SR-like strategy, contributes to human behavior, but that high-risk drinkers do not differ from low-risk drinkers in their use of this strategy. Instead, both groups seem to rely less on what is likely a (reduced) random-policy SR strategy in alcohol-related contexts – and instead more on model-free control. Results suggest that the use of an adaptive, resource-efficient decision-making strategy is selectively downregulated in substance-related contexts. This study highlights the importance of considering contextual modulation and nuanced decision strategies in understanding habitual and goal-directed behavior in mental health conditions such as addiction. Author summary: Humans can behave in more habitual or more goal-directed ways, like when routinely brushing our teeth versus planning how to circumvent a construction site. Mental health conditions such as addiction have been suggested to involve a shift from goal-directed to habitual behavior, but the evidence is inconsistent. This might be due to how habits have been assessed in the laboratory: tasks usually take place in contexts unrelated to the disorder and cannot detect the use of strategies with subtle characteristics of habitual behavior. Here, we set out to determine the role of one such strategy, the successor representation, in high-risk drinking and alcohol-related contexts. While we found no increased use of this strategy in high-risk drinking, individuals likely relied less on a successor representation-based strategy in a virtual bar environment compared to a non-alcohol-related context. Drug-associated settings thus seem to be associated with diminished reliance on a generally adaptive, efficient behavioral strategy. Our findings highlight that, to understand the role of habits in mental health conditions, we need to consider decision-making strategies along a continuum between goal-directed and habitual control and, importantly, disorder-relevant contexts.", "abstract_shown": true, "affiliations": [ "Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Psychiatry and Neurosciences | CCM, NeuroCure Clinical Research Center, Berlin, Germany", "Humboldt-Universität zu Berlin, Faculty of Life Sciences, Department of Psychology, Berlin, Germany", "Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Einstein Center for Neurosciences Berlin, Berlin, Germany", "Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Bernstein Center for Computational Neuroscience, Berlin, Germany", "Department of Psychology and Center for Brain Science, Harvard University, Cambridge, Massachusetts, United States of America", "Graduate School of Education, The University of Tokyo, Tokyo, Japan", "Japan Society for the Promotion of Science, Tokyo, Japan", "Department of Information Medicine, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan", "Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America", "Department of Psychiatry and Behavioral Sciences, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, Japan", "Well-Vitality Visionary Initiative, Institute of Science Tokyo, Tokyo, Japan", "Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany", "International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, Tokyo, Japan" ], "article_type": "Research Article", "arxiv": null, "author_total": 11, "authors": [ { "affs": [ 0, 1, 2, 3 ], "name": "Milena P. M. Musial", "orcid": "0000-0002-8365-5111" }, { "affs": [ 4 ], "name": "Sam Hall-McMaster" }, { "affs": [ 5, 6, 7 ], "name": "Kanji Shimomura" }, { "affs": [ 8, 9, 10 ], "name": "Ayaka Kato" }, { "affs": [ 0, 1, 2 ], "name": "Erik L. Bode", "orcid": "0009-0001-6138-8040" }, { "affs": [ 11 ], "name": "Clarissa C. Grundmann" }, { "affs": [ 0 ], "name": "Claudia Ebrahimi" }, { "affs": [ 5, 12 ], "name": "Kenji Morita", "orcid": "0000-0003-2192-4248" }, { "affs": [ 4 ], "name": "Samuel J. Gershman" }, { "affs": [ 11 ], "name": "Tanja Endrass" }, { "affs": [ 0, 2, 3 ], "name": "Florian Schlagenhauf" } ], "bibtex": "https://research.draconitic.com/paper/e9cpvxdr2jmcf.bib", "cited_by": 0, "doi": "10.1371/journal.pcbi.1014873", "fulltext_url": "https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1014873", "id": "e9cpvxdr2jmcf", "issns": [ "1553-7358", "1553-734X" ], "landing_url": "https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1014873", "language": "en", "licence": "CC-BY-4.0", "licence_label": "CC BY 4.0", "licence_source": "article", "licence_url": "https://creativecommons.org/licenses/by/4.0/", "metadata_licence": null, "native_subjects": [ [ "heading", "Addiction" ], [ "heading", "Alcohol Consumption" ], [ "heading", "Algorithms" ], [ "heading", "Applied Mathematics" ], [ "heading", "Behavior" ], [ "heading", "Behavioral Addiction" ], [ "heading", "Biology and Life Sciences" ], [ "heading", "Cognition" ], [ "heading", "Cognitive Psychology" ], [ "heading", "Cognitive Science" ], [ "heading", "Decision Making" ], [ "heading", "Diet" ], [ "heading", "Drug Addiction" ], [ "heading", "Habits" ], [ "heading", "Human Performance" ], [ "heading", "Learning" ], [ "heading", "Learning and Memory" ], [ "heading", "Mathematics" ], [ "heading", "Medicine and Health Sciences" ], [ "heading", "Mental Health and Psychiatry" ], [ "heading", "Neuroscience" ], [ "heading", "Nutrition" ], [ "heading", "Physical Sciences" ], [ "heading", "Psychology" ], [ "heading", "Public and Occupational Health" ], [ "heading", "Research Article" ], [ "heading", "Research and Analysis Methods" ], [ "heading", "Simulation and Modeling" ], [ "heading", "Social Sciences" ], [ "heading", "Substance-Related Disorders" ], [ "openalex", "2805|Neural and Behavioral Psychology Studies" ], [ "plos", "/Biology and life sciences/Neuroscience/Cognitive science/Cognition/Decision making" ], [ "plos", "/Biology and life sciences/Neuroscience/Cognitive science/Cognitive psychology/Decision making" ], [ "plos", "/Biology and life sciences/Neuroscience/Cognitive science/Cognitive psychology/Learning" ], [ "plos", "/Biology and life sciences/Neuroscience/Learning and memory/Learning" ], [ "plos", "/Biology and life sciences/Nutrition/Diet/Alcohol consumption" ], [ "plos", "/Biology and life sciences/Psychology/Addiction/Behavioral addiction" ], [ "plos", "/Biology and life sciences/Psychology/Addiction/Drug addiction" ], [ "plos", "/Biology and life sciences/Psychology/Behavior/Habits" ], [ "plos", "/Biology and life sciences/Psychology/Behavior/Human performance" ], [ "plos", "/Biology and life sciences/Psychology/Cognitive psychology/Decision making" ], [ "plos", "/Biology and life sciences/Psychology/Cognitive psychology/Learning" ], [ "plos", "/Medicine and health sciences/Mental health and psychiatry/Substance-related disorders/Drug addiction" ], [ "plos", "/Medicine and health sciences/Nutrition/Diet/Alcohol consumption" ], [ "plos", "/Medicine and health sciences/Public and occupational health/Substance-related disorders/Drug addiction" ], [ "plos", "/Physical sciences/Mathematics/Applied mathematics/Algorithms" ], [ "plos", "/Research and analysis methods/Simulation and modeling/Algorithms" ], [ "plos", "/Social sciences/Psychology/Addiction/Behavioral addiction" ], [ "plos", "/Social sciences/Psychology/Addiction/Drug addiction" ], [ "plos", "/Social sciences/Psychology/Behavior/Habits" ], [ "plos", "/Social sciences/Psychology/Behavior/Human performance" ], [ "plos", "/Social sciences/Psychology/Cognitive psychology/Decision making" ], [ "plos", "/Social sciences/Psychology/Cognitive psychology/Learning" ] ], "openalex": "W7223116929", "pdf_url": "https://journals.plos.org/ploscompbiol/article/file?id=10.1371/journal.pcbi.1014873&type=printable", "pmcid": "PMC13716319", "pmid": "42905773", "published": "2026-10-21", "publisher": "Public Library of Science", "ris": "https://research.draconitic.com/paper/e9cpvxdr2jmcf.ris", "sources": [ { "first_seen": "2026-10-30T12:17:23Z", "native_id": "10.1371/journal.pcbi.1014873", "source": "plos", "url": "https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1014873" }, { "first_seen": "2026-11-01T12:23:21Z", "native_id": "PMC13716319", "source": "pmc", "url": "https://doi.org/10.1371/journal.pcbi.1014873" } ], "subjects": [ { "field": "biology", "origin": "plos:neuroscience", "subfield": "neuroscience" }, { "field": "mathematics", "origin": "heading:Mathematics", "subfield": "general" }, { "field": "medicine", "origin": "heading:Public and Occupational Health", "subfield": "epidemiology-public-health" }, { "field": "medicine", "origin": "plos:nutrition", "subfield": "nutrition" }, { "field": "medicine", "origin": "heading:Mental Health and Psychiatry", "subfield": "psychiatry" } ], "title": "The successor representation in high-risk drinking and alcohol-related contexts", "title_text": "The successor representation in high-risk drinking and alcohol-related contexts", "type": "peer-reviewed", "updated_at": "2026-11-01T12:23:21Z", "url": "https://research.draconitic.com/paper/e9cpvxdr2jmcf", "venue": "PLOS Computational Biology", "versions": [] }