title: Intertemporal choice behavior is constrained by brain structure in healthy participants and pathological gamblers.
abstract: The steepness of the delay discounting function shows considerable interindividual differences. Moreover, faster devaluation of future rewards has been consistently observed in pathological gamblers (PGs). Here, we asked whether variability in delay discounting is at least partially driven by differences in the anatomy of gray and white matter. For 40 healthy young subjects (study 1) as well as 15 PG and 15 age-matched healthy controls (HCs, study 2), the individual discounting parameter k was obtained. Based on 3D T1-weighted high-resolution magnetic resonance scans and diffusion tensor imaging, we performed voxel-based morphometry and tract-based spatial statistics, respectively, to examine the relation of gray matter volume (GMV) and white matter properties (as indicated by fractional anisotropy, FA) to k. Healthy groups from both studies showed a negative correlation between k and FA for the superior longitudinal fascicle and inferior longitudinal fascicle, whereas a positive correlation was found in the PG group for the inferior longitudinal fascicle and left inferior fronto-occipital fascicle. The latter also was significantly different between HC and PG in the group statistics (albeit on the right side), thus suggesting that this is a significant structure for the development of pathological gambling. GMV of the right frontal orbital cortex, left insular cortex and right lateral occipital cortex showed a positive correlation to k HC (studies 1 and 2) and PG, whereas a negative correlation was found for the left frontal pole in all three groups. Group comparison of GMV (study 2) revealed a decrease in PG for several cortical and subcortical areas.
authors.affiliation: Department of Neurology, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany.|International Neuroscience Institute, Hannover, Germany.
authors.forename: Bahram
authors.initials: B
authors.lastname: Mohammadi
authors.affiliation: Department of Neurology, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany.|Department of Psychiatry, University of Erlangen, Erlangen, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Hammer
authors.affiliation: Institute of Psychology, University of Salzburg, Salzburg, Austria.|Department of Neuropsychology and Behavioral Neurobiology, University of Bremen, Bremen, Germany.
authors.forename: Stephan F
authors.initials: SF
authors.lastname: Miedl
authors.affiliation: Department of Neurology, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany.|Institute of Psychology II, University of Lübeck, Lübeck, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wiswede
authors.affiliation: Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Marco-Pallarés
authors.affiliation: Department of Neuropsychology and Behavioral Neurobiology, University of Bremen, Bremen, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Herrmann
authors.affiliation: 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.forename: Thomas F
authors.initials: TF
authors.lastname: Münte
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology*; D065786:Delay Discounting / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D005260:Female; D005715:Gambling / Q000473:pathology / Q000503:physiopathology*; D066128:Gray Matter / Q000473:pathology / Q000502:physiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D012201:Reward; D066127:White Matter / Q000473:pathology / Q000502:physiology / Q000503:physiopathology; D055815:Young Adult
keywords: Delay discounting; Diffusion tensor imaging; Intertemporal choice; Pathological gambling; Reward; Voxel-based morphometry; fMRI