Effects of Medial Orbitofrontal Cortex Lesions on Self-Control in Intertemporal Choice.
Many decisions involve a trade-off between the temporal proximity of a reward and its magnitude. A range of clinical conditions are associated with poor self-control during such intertemporal choices, such that smaller rewards that are received sooner are preferred over larger rewards that are received later to a greater extent [1, 2]. According to a prominent neural model of self-control [3-6], subjective reward values are represented in the medial orbitofrontal cortex (mOFC) at the time of choice [7-9]. Successful self-control in this model is then thought to depend on a modulation of these mOFC value representations via the lateral prefrontal cortex (lPFC) [3, 6]. Here we directly tested three key predictions of this model in patients with lesions to the mOFC (n = 9) and matched controls (n = 19). First, we show that mOFC lesions disrupt choice-free valuation ratings. This finding provides causal evidence for a role of the mOFC in reward valuation and contrasts with the effects of lPFC disruption [6]. Second, we show that mOFC damage indeed decreases self-control during intertemporal choice, replicating previous findings [10]. Third, extending these previous observations, we show that the effect of mOFC damage on intertemporal choice depends on the actual self-control demands of the task. Our findings thus provide causal evidence for a role of mOFC in reward valuation and are compatible with the idea that mOFC damage affects self-control specifically under conditions that might normally require a modulation of mOFC value representations, e.g., by the lPFC.
Department of Psychology, Biological Psychology, University of Cologne, Albertus-Magnus-Platz, 50923 Cologne, Germany; Institute of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany. Electronic address: jan.peters@uni-koeln.de.
Jan
J
Peters
Helen Wills Neuroscience Institute, 132 Barker Hall, University of California, Berkeley, Berkeley, CA 94720, USA. Electronic address: despo@berkeley.edu.
Mark
M
D'Esposito
D000328:Adult; D000368:Aged; D000070642:Brain Injuries, Traumatic / Q000473:pathology; D001932:Brain Neoplasms / Q000473:pathology / Q000601:surgery; D002755:Choice Behavior; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000473:pathology*; D012201:Reward; D000068356:Self-Control