title: Behavioral and neuroimaging evidence for overreliance on habit learning in alcohol-dependent patients.
abstract: Substance dependence is characterized by compulsive drug-taking despite negative consequences. Animal research suggests an underlying imbalance between goal-directed and habitual action control with chronic drug use. However, this imbalance, and its associated neurophysiological mechanisms, has not yet been experimentally investigated in human drug abusers. The aim of the present study therefore was to assess the balance between goal-directed and habit-based learning and its neural correlates in abstinent alcohol-dependent (AD) patients. A total of 31 AD patients and 19 age, gender and education matched healthy controls (HC) underwent functional magnetic resonance imaging (fMRI) during completion of an instrumental learning task designed to study the balance between goal-directed and habit learning. Task performance and task-related blood oxygen level-dependent activations in the brain were compared between AD patients and healthy matched controls. Findings were additionally associated with duration and severity of alcohol dependence. The results of this study provide evidence for an overreliance on stimulus-response habit learning in AD compared with HC, which was accompanied by decreased engagement of brain areas implicated in goal-directed action (ventromedial prefrontal cortex and anterior putamen) and increased recruitment of brain areas implicated in habit learning (posterior putamen) in AD patients. In conclusion, this is the first human study to provide experimental evidence for a disturbed balance between goal-directed and habitual control by use of an instrumental learning task, and to directly implicate cortical dysfunction to overreliance on inflexible habits in AD patients.
authors.affiliation: 1] Department of Psychiatry, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands [2] Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Z
authors.initials: Z
authors.lastname: Sjoerds
authors.affiliation: 1] Department of Clinical Psychology, University of Amsterdam, Amsterdam, The Netherlands [2] Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: de Wit
authors.affiliation: Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: W
authors.initials: W
authors.lastname: van den Brink
authors.affiliation: Department of Experimental Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK.
authors.forename: T W
authors.initials: TW
authors.lastname: Robbins
authors.affiliation: Department of Psychiatry, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: A T F
authors.initials: AT
authors.lastname: Beekman
authors.affiliation: 1] Department of Psychiatry, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands [2] Department of Psychiatry, Leiden University Medical Center, Leiden, The Netherlands [3] Department of Psychiatry, University Medical Center of Groningen, Groningen, The Netherlands.
authors.forename: B W J H
authors.initials: BW
authors.lastname: Penninx
authors.affiliation: 1] Department of Psychiatry, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands [2] Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: D J
authors.initials: DJ
authors.lastname: Veltman
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000378:metabolism / Q000503:physiopathology*; D001921:Brain / Q000378:metabolism / Q000503:physiopathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D003216:Conditioning, Operant / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology*; D005260:Female; D059907:Functional Neuroimaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000378:metabolism / Q000503:physiopathology; D011699:Putamen / Q000378:metabolism / Q000503:physiopathology; D012720:Severity of Illness Index