title: Impulsive personality and the ability to resist immediate reward: an fMRI study examining interindividual differences in the neural mechanisms underlying self-control.
abstract: The ability to resist immediate rewards is crucial for lifetime success and individual well-being. Using functional magnetic resonance imaging, we assessed the association between trait impulsivity and the neural underpinnings of the ability to control immediate reward desiring. Low and high extreme impulsivity groups were compared with regard to their behavioral performance and brain activation in situations, in which they had to forego immediate rewards with varying value to achieve a superordinate long-term goal. We found that highly impulsive (HI) individuals, who successfully compensated for their lack in behavioral self-control, engaged two complementary brain mechanisms when choosing actions in favor of a long-term goal, but at the expense of an immediate reward. First, self-controlled decisions led to a general attenuation of reward-related activation in the nucleus accumbens, which was accompanied by an increased inverse connectivity with the anteroventral prefrontal cortex. Second, HI subjects controlled their desire for increasingly valuable, but suboptimal rewards through a linear reduction of activation in the ventromedial prefrontal cortex (VMPFC). This was achieved by an increased inverse coupling between the VMPFC and the ventral striatum. Importantly, the neural mechanisms observed in the HI group differed from those in extremely controlled individuals, despite similar behavioral performance. Collectively, these results suggest trait-specific neural mechanisms that allow HI individuals to control their desire for immediate reward.
authors.affiliation: Department of Psychiatry and Psychotherapy, Center for Translational Research in Systems Neuroscience and Psychiatry, Georg August University, Von-Siebold-Strasse 5,Goettingen, Germany. e.diekhof@gmx.de
authors.forename: Esther Kristina
authors.initials: EK
authors.lastname: Diekhof
authors.forename: Lesly
authors.initials: L
authors.lastname: Nerenberg
authors.forename: Peter
authors.initials: P
authors.lastname: Falkai
authors.forename: Peter
authors.initials: P
authors.lastname: Dechent
authors.forename: Jürgen
authors.initials: J
authors.lastname: Baudewig
authors.forename: Oliver
authors.initials: O
authors.lastname: Gruber
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology* / Q000503:physiopathology; D003657:Decision Making; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007175:Impulsive Behavior / Q000503:physiopathology*; D007206:Individuality; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009042:Motivation; D009415:Nerve Net / Q000502:physiology / Q000503:physiopathology; D009434:Neural Pathways / Q000502:physiology; D009483:Neuropsychological Tests; D010551:Personality / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012201:Reward; D012927:Social Control, Informal