title: Action-value comparisons in the dorsolateral prefrontal cortex control choice between goal-directed actions.
abstract: It is generally assumed that choice between different actions reflects the difference between their action values yet little direct evidence confirming this assumption has been reported. Here we assess whether the brain calculates the absolute difference between action values or their relative advantage, that is, the probability that one action is better than the other alternatives. We use a two-armed bandit task during functional magnetic resonance imaging and modelled responses to determine both the size of the difference between action values (D) and the probability that one action value is better (P). The results show haemodynamic signals corresponding to P in right dorsolateral prefrontal cortex (dlPFC) together with evidence that these signals modulate motor cortex activity in an action-specific manner. We find no significant activity related to D. These findings demonstrate that a distinct neuronal population mediates action-value comparisons, and reveals how these comparisons are implemented to mediate value-based decision-making.
authors: 1] Brain & Mind Research Institute, University of Sydney, Sydney, 2021 New South Wales, Australia [2].
authors: Richard W
authors: RW
authors: Morris
authors: 1] Brain & Mind Research Institute, University of Sydney, Sydney, 2021 New South Wales, Australia [2].
authors: Amir
authors: A
authors: Dezfouli
authors: Brain & Mind Research Institute, University of Sydney, Sydney, 2021 New South Wales, Australia.
authors: Kristi R
authors: KR
authors: Griffiths
authors: Brain & Mind Research Institute, University of Sydney, Sydney, 2021 New South Wales, Australia.
authors: Bernard W
authors: BW
authors: Balleine
mesh_terms: D000293:Adolescent; D000328:Adult; D001499:Bayes Theorem; D001931:Brain Mapping; D002755:Choice Behavior / Q000502:physiology*; D003657:Decision Making / Q000502:physiology*; D005260:Female; D006040:Goals; D006801:Humans; D007858:Learning / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D015233:Models, Statistical; D017397:Prefrontal Cortex / Q000033:anatomy & histology* / Q000502:physiology*; D013647:Task Performance and Analysis; D055815:Young Adult