title: A Computational Analysis of Aberrant Delay Discounting in Psychiatric Disorders.
abstract: Impatience for reward is a facet of many psychiatric disorders. We draw attention to a growing literature finding greater discounting of delayed reward, an important aspect of impatience, across a range of psychiatric disorders. We propose these findings are best understood by considering the goals and motivation for discounting future reward. We characterize these as arising from either the opportunity costs of waiting or the uncertainty associated with delayed reward. We link specific instances of higher discounting in psychiatric disorder to heightened subjective estimates of either of these factors. We propose these costs are learned and represented based either on a flexible cognitive model of the world, an accumulation of previous experience, or through evolutionary specification. Any of these can be considered suboptimal for the individual if the resulting behavior results in impairments in personal and social functioning and/or in distress. By considering the neurochemical and neuroanatomical implementation of these processes, we illustrate how this approach can in principle unite social, psychological and biological conceptions of impulsive choice.
authors.affiliation: Max Planck University College London Centre for Computational Psychiatry and Ageing Research, University College LondonLondon, UK; Wellcome Trust Centre for Neuroimaging, University College LondonLondon, UK; Centre for Health Policy, Imperial College London, Institute of Global Health Innovation, St. Mary's HospitalLondon, UK.
authors.forename: Giles W
authors.initials: GW
authors.lastname: Story
authors.affiliation: Max Planck University College London Centre for Computational Psychiatry and Ageing Research, University College LondonLondon, UK; Wellcome Trust Centre for Neuroimaging, University College LondonLondon, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Moutoussis
authors.affiliation: Max Planck University College London Centre for Computational Psychiatry and Ageing Research, University College LondonLondon, UK; Wellcome Trust Centre for Neuroimaging, University College LondonLondon, UK.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Dolan
keywords: biopsychosocial; computational psychiatry; discounting; mental illness; psychiatric; time preference