title: The neural basis of impulsive discounting in pathological gamblers.
abstract: Pathological gambling is thought to result from a shift of balance between two competing neurobiological mechanisms: on the one hand the reward system involved in the regulation of the urge to get rewards and on the other hand the top-down control system. Fifteen pathological gamblers (PG) and fifteen healthy controls (HC) were studied in an event-related functional magnetic resonance imaging experiment where participants had to choose either a smaller, but immediately available monetary reward (SIR) or a larger delayed reward (LDR). We examined contrasts between LDR and SIR decisions. Additionally, we contrasted choices near the individual indifference point (indifferent decisions) and clear SIR or LDR choices (sure decisions). Behavioral data confirmed former results of steeper discount rates in PG. Contrasting choices of LDR vs. SIR showed widespread bilateral activations in PG, including postcentral gyrus, thalamus, superior/medial frontal gyrus and cingulate gyrus, whereas HC demonstrated only focal left-sided pre/postcentral activity. Forgoing an immediate reward thus recruits a widespread brain network including typical control areas. Indifferent vs. sure decisions were associated with widespread activation in PG, including the bilateral fronto-parietal cortex, insula, anterior cingulate gyrus, and striatum, whereas in HC, only bilateral frontal cortex and insula were activated. The reverse contrast demonstrated more activity for sure decisions in the cingulate gyrus, insula, and medial frontal gyrus in HC, whereas PG showed inferior parietal and superior temporal activity. The present study demonstrates that pathological gambling is associated with a shift in the interplay between a prefrontal-parietal control network and a brain network involved in immediate reward consumption.
authors: Department of Psychology, University of Salzburg, Salzburg, Austria.
authors: Stephan F
authors: SF
authors: Miedl
authors: Department of Neurology, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany.
authors: Daniel
authors: D
authors: Wiswede
authors: Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Barcelona, Spain.|Department of Basic Psychology, University of Barcelona, Barcelona, Germany.
authors: Josep
authors: J
authors: Marco-Pallarés
authors: Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
authors: Zheng
authors: Z
authors: Ye
authors: Department of Neuropsychology, University of Bremen, Bremen, Germany.
authors: Thorsten
authors: T
authors: Fehr
authors: Department of Neuropsychology, University of Bremen, Bremen, Germany.
authors: Manfred
authors: M
authors: Herrmann
authors: Department of Neurology, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany. thomas.muente@neuro.uni-luebeck.de.|Institute of Psychology II, University of Lübeck, Lübeck, Germany. thomas.muente@neuro.uni-luebeck.de.
authors: Thomas F
authors: TF
authors: Münte
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D003220:Conflict, Psychological; D065786:Delay Discounting / Q000502:physiology*; D005715:Gambling / Q000503:physiopathology* / Q000523:psychology; D006801:Humans; D007175:Impulsive Behavior / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000503:physiopathology; D009483:Neuropsychological Tests; D012201:Reward
keywords: Delay discounting; Intertemporal choice; Pathological gambling; Reward; fMRI