Preference for Immediate over Delayed Rewards Is Associated with Magnitude of Ventral Striatal Activity

Abstract

Discounting future outcomes as a function of their deferred availability underlies much of human decision making. Discounting, or preference for immediate over delayed rewards of larger value, is often associated with impulsivity and is a risk factor for addictive disorders such as pathological gambling, cigarette smoking, and drug and alcohol abuse. The ventral striatum (VS) is involved in mediating behavioral responses and physiological states associated with reward, and dysregulation of the VS contributes to addiction, perhaps by affecting impulsive decision-making. Behavioral tests of delay discounting (DD), which index preference for smaller immediate over larger delayed rewards, covary with impulsive tendencies in humans. In the current study, we examined the relationship between individual differences in DD, measured in a behavioral assessment, and VS activity measured with blood oxygenation leveldependent functional magnetic resonance imaging, in 45 adult volunteers. VS activity was determined using a task involving positive and negative feedback with monetary reward. Analyses revealed that individual differences in DD correlate positively with magnitude of VS activation in response to both positive and negative feedback, compared with a no-feedback control condition. Variability in DD was also associated with differential VS activation in response to positive, compared with negative, feedback. Collectively, our results suggest that increased preference for smaller immediate over larger delayed rewards reflects both a relatively indiscriminate and hyper-reactive VS circuitry. They also highlight a specific neurocognitive mechanism that may contribute to increased risk for addiction.

Affect as a Decision-Making System of the Present

“…Using fMRI, McClure et al (2004) found that in intertemporal choice tasks, areas of the brain that are closely associated with emotions, such as the limbic area and the medial prefrontal cortex, become activated only in choices that involve immediate monetary outcomes (see also Hariri et al 2006). Similar results have been observed with nonmonetary rewards (McClure et al 2007).…”

The neural basis of cultural differences in delay discounting

“…This analysis localizes brain areas associated with emotional responsivity [7,24] and cognitive control [5,8], respectively. To perform this analysis, we combined both subject groups and conducted a voxel-wise, event related GLM analysis.…”

“…Neurally, these process are linked to brain reward areas (including the ventral striatum, VStr, and ventromedial prefrontal cortex, VMPFC) and regions associated with executive functions (dorsolateral prefrontal cortex, DLPFC, and posterior parietal cortex, PPC), respectively [4 -6]. Individual differences in either reward-or executive control-related brain responses both predict rates of delay discounting [7,8].…”

fMRI Evidence of a Hot-Cold Empathy Gap in Hypothetical and Real Aversive Choices

“…In public economics and political science, survey data are used to establish the dollar value of goods that are not traded in markets (such as clean air or the prevention of oil spills), and to poll likely voters before an election (Crespi, 1989;Diamond and Hausman, 1994;Carson et al, 1996;Mortimer and Segal, 2008). Hypothetical choices are also necessary in some types of psychology and neuroscience experiments in which measuring real choices is impractical or unethical, especially in the domain of distressing moral choices (Greene et al, 2001(Greene et al, , 2004Kühberger et al, 2002;Hariri et al, 2006;Monterosso et al, 2007).…”

“…In public economics and political science, survey data are used to establish the dollar value of goods that are not traded in markets (such as clean air or the prevention of oil spills), and to poll likely voters before an election (Crespi, 1989;Diamond and Hausman, 1994;Carson et al, 1996;Mortimer and Segal, 2008). Hypothetical choices are also necessary in some types of psychology and neuroscience experiments in which measuring real choices is impractical or unethical, especially in the domain of distressing moral choices (Greene et al, 2001(Greene et al, , 2004Kühberger et al, 2002;Hariri et al, 2006;Monterosso et al, 2007).The reliance on hypothetical choice data presumes either that hypothetical choices are a good and legitimate way to forecast real choices, or that there is some knowable relationship between the two types of choices, such that the hypothetical data can be adjusted to forecast real choice data accurately.Abbreviations: WTP, willingness-to-pay; CS, consumer surplus.However, many studies in behavioral economics have shown a substantial, systematic gap: typically, hypothetical valuations are greater than real valuations (Cummings et al, 1995;Johannesson et al, 1998;List and Gallet, 2001;Ariely and Wertenbroch, 2002;Little and Berrens, 2004;Murphy et al, 2005;Blumenschein et al, 2007;Tanner and Carlson, 2009). To remedy this typical upward "Yes" bias, in marketing research conjoint analysis using hypothetical preference data has been extended and improved through hybrid incentive-aligned methods in which an inferred choice will be implemented for real (Ding et al, 2005;Ding, 2007;Dong et al, 2010).…”