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Cited by 604Decision-Making and Behavioral EconomicsNeural and Behavioral Psychology StudiesGambling Behavior and Treatments

Excessive discounting of delayed reinforcers as a trans-disease process contributing to addiction and other disease-related vulnerabilities: Emerging evidence

Open access
Bickel, Warren K., Jarmolowicz, David P., Mueller, E. Terry, Koffarnus, Mikhail N., Gatchalian, Kirstin M.·2012·Pharmacology & Therapeutics
DOI 10.1016/j.pharmthera.2012.02.004PMC PMC3329584
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Abstract

Delay discounting describes the devaluation of a reinforcer as a function of the delay until its receipt. Although all people discount delayed reinforcers, one consistent finding is that substance-dependent individuals tend to discount delayed reinforcers more rapidly than do healthy controls. Moreover, these higher-than-normal discounting rates have been observed in individuals with other behavioral maladies such as pathological gambling, poor health behavior, and overeating. This suggests that high rates of delay discounting may be a trans-disease process (i.e., a process that occurs across a range of disorders, making findings from one disorder relevant to other disorders). In this paper, we argue that delay discounting is a trans-disease process, undergirded by an imbalance between two competing neurobehavioral decision systems. Implications for our understanding of, and treatment for, this trans-disease process are discussed.

AI snapshot

Written from the paper’s full text.

TL;DR

This review argues that excessive delay discounting is a trans-disease process cutting across addiction, gambling, obesity, risky health behaviors, and psychiatric disorders, with the competing neurobehavioral decision systems (CNDS) theory proposed as its neurobiological basis. It suggests that interventions restoring balance between impulsive and executive systems, such as working memory training, may reduce discounting and improve treatment across disorders.

Key findings

  • Excessive delay discounting is consistently higher in substance-dependent groups than controls; for example, Madden et al. (1997) reported opioid-dependent individuals with k = 0.220 versus controls with k = 0.027 for hypothetical $1,000 reinforcers, with replications across opioid, cigarette, alcohol, and cocaine dependence.
  • Excessive discounting extends beyond addiction to problem gambling, obesity/binge eating disorder, risky sexual behavior and HIV risk, poor health behaviors, ADHD, schizophrenia, borderline personality disorder, depression, social anxiety, and disruptive behavior disorder; comorbidity may be additive, as substance abusers with pathological gambling had higher discounting than substance abusers who seldom gambled, while controls had the lowest rates.
  • CNDS theory posits that choices reflect a regulatory balance between an evolutionarily older impulsive limbic/paralimbic system valuing immediate rewards and a more recently developed executive prefrontal system valuing delayed rewards; fMRI evidence links immediate choices to limbic activation and delayed choices to prefrontal activation, and addiction may involve a hyperactive impulsive and/or hypoactive executive system.
  • Working memory training in stimulant users with working memory deficits and excessive discounting reduced delay-discounting rates in the active training group while control-group rates remained unchanged (Bickel et al., 2011); cognitive enhancers, TMS, and real-time fMRI are proposed as potential complementary treatments.

Methods

  • Narrative review and conceptual synthesis; no new empirical data are reported. The paper reviews delay-discounting procedures, the hyperbolic discounting model V = A/(1 + kD), and the CNDS framework.
  • Evidence is drawn from prior human and animal studies, including clinical samples (opioid-, cocaine-, alcohol-, and nicotine-dependent individuals; gamblers; obese individuals; ADHD; schizophrenia; HIV/hepatitis C) and nonclinical/epidemiological samples such as n = 947 adolescents, n = 1042 adolescents, 467 college students, and 987 retirement-age adults.
  • Main analysis is qualitative integration of findings across disorders and across neuroimaging, pharmacological, and cognitive-training studies; no meta-analysis or systematic search strategy is described.

Limitations

  • The paper states that cross-sectional designs make it difficult to determine whether elevated discounting predisposes individuals to addiction or results from ongoing substance use; few longitudinal studies exist, acute drug effects on discounting are inconsistent and likely due to procedural differences, and animal-human inconsistencies complicate extrapolation.
  • The paper notes that some elevated discounting findings may be confounded by lower IQ/working memory or high smoking rates (e.g., ADHD, schizophrenia), that it is unknown whether brain structural differences predate or result from prolonged drug use, and that treatment potential depends on whether discounting is trait-like or state-like.
  • Evident from the text: as a narrative review, it does not systematically search or quantitatively synthesize the literature, and its treatment implications are largely preliminary or proposed rather than tested in this paper.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.pharmthera.2012.02.004

Cites

191 of 191 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 100 cited sources checked · 0 supported · 0 flagged

  • Interpretationreasoning

    Existing studies of situational drug deprivation provide qualified support for an association between abnormally high delay discounting and the extent to which a drug is reinforcing.

    “existing studies of situational drug deprivation provide qualified support for the association between abnormally high rates of delay discounting and the extent to which a drug is reinforcing.”
    Quote in the paperSubstantial claim
  • Interpretationcitation

    Greater severity of substance abuse may be associated with higher rates of delay discounting.

    “their findings suggest that the severity of substance abuse may be correlated with degree of delay discounting.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Vuchinich and Simpson (1998) source

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  • Premisecitation

    Mild opioid deprivation increased rates of delay discounting for heroin and for money.

    “mild opioid deprivation increased rates of delay discounting for heroin and for money.”
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    • cites Giordano et al. (2002) source

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  • Premisecitation

    Hyperbolic functions better describe existing delay-discounting data than exponential functions.

    “considerable data suggest that the hyperbolic functions favored in behavioral economics (Mazur, 1987) better describe existing data”
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  • Interpretationreasoning

    High rates of delay discounting may be a trans-disease process.

    “This suggests that high rates of delay discounting may be a trans-disease process”
    Quote in the paperSubstantial claim
  • May combine two claims. 26
  • Classified as probably not a substantial claim. 6

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    Premisecitation

    Delay discounting predicted entry into smoking and increases in smoking rates.

    “delay discounting predicted entry into smoking and increases in smoking rates.”
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    • cites Audrain-McGovern et al. (2009a)

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    Interpretationreasoning

    Delay discounting is a trans-disease process that co-occurs across a range of addictions.

    “The literature reviewed above suggests that delay discounting is a trans-disease process that co-occurs across a range of addictions.”
    Quote in the paperSubstantial claim

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    Premisecitation

    Discounting rates were highest in current smokers and did not differ between former and never smokers.

    “although discounting rates were highest in the current smokers, discounting rates did not differ between the former and never smokers.”
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    • cites Bickel et al. (1999) source

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    Premisecitation

    Deprivation increased discounting rate for cigarettes but not for money.

    “Mitchell (2004), however, found that deprivation increased discounting rate for cigarettes but not for money.”
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    Premisecitation

    The contemporary analysis of disease suggests that each disease has its own etiology.

    “the contemporary analysis of disease suggests that each disease has its own etiology.”
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    • cites Bickel & Mueller, 2009

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    Premisecitation

    Delay discounting rates are positively correlated with frequency of alcohol and cigarette use.

    “delay discounting rates are positively correlated with ones’ frequency of alcohol (Takahashi et al., 2009) and cigarette (Ohmura et al., 2005) use”
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    Premisecitation

    Similar findings to Bickel et al. (1999) were observed in smokers who cut down and in discounting of health outcomes in cigarette smokers.

    “There have been similar findings in a study wherein smokers were required not to quit smoking, but to cut down on the number of cigarettes they smoked (Yi et al., 2008), and in a study that assessed the discounting of health outcomes in cigarette smokers (Odum et al., 2002).”
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    Premisenone given

    Excessively high rates of delay discounting are characteristic of individuals with gambling problems, the obese, those engaging in unhealthy actions such as risky sexual behavior, and individuals diagnosed with ADHD or schizophrenia.

    “excessively high rates of delay discounting are characteristic of individuals with gambling problems, the obese, those who engage in unhealthy actions such as risky sexual behavior, and individuals diagnosed with ADHD or schizophrenia.”
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    Interpretationreasoning

    The presumption of distinctive etiologies combines with specialized research training to promote a reductionist approach to science.

    “The presumption of distinctive etiologies for each disease combines with the need for increasingly specialized research training of scientists to promote a reductionist approach to science”
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    Premisenone given

    Loss of control over drug-seeking behavior and excessive rates of discounting both characterize addiction.

    “Loss of control over drug-seeking behavior and excessive rates of discounting both characterize addiction.”
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    Premisecitation

    d-Amphetamine decreases delay-discounting rates in humans, while animal studies show increases, decreases, or no effect.

    “while d-amphetamine has been shown to decrease delay-discounting rates in humans (de Wit et al., 2002), animal studies show increases (e.g., Evenden & Ryan, 1996), decreases (e.g., van Gaalen et al., 2006) or no effect (e.g., Uslaner & Robinson, 2006) on discounting rates.”
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    Premisecitation

    Substance abusers who were pathological gamblers had higher delay discounting rates than substance abusers who seldom gambled, and controls who did not abuse substances or gamble had the lowest discounting rates.

    “Petry and Casarella (1999) found that substance abusers who were pathological gamblers had higher delay discounting rates than substance abusers who seldom gambled, and controls that did not abuse substances or gamble had the lowest discounting rates.”
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    • cites Petry and Casarella (1999) source

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    Premisecitation

    Acute alcohol administration has been shown to increase, decrease, or have no effect on discounting rates.

    “acute alcohol administration has been shown to increase (Reynolds et al., 2006), decrease (Ortner et al., 2003), or have no effect on (Richards et al., 1999) discounting rates.”
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    Premisecitation

    Individuals abuse and become addicted to drugs that have a rapid and powerful onset.

    “individuals abuse and become addicted to drugs that have a rapid and powerful onset”
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    • cites Bickel, Jarmolowicz et al., in press

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    • cites Schuster & Thompson, 1969

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    Interpretationreasoning

    Elevated discounting rates may predispose individuals to addiction, while ongoing use may result in even higher rates of discounting.

    “although elevated discounting rates may predispose individuals to addiction, ongoing use may result in even higher rates of discounting.”
    Quote in the paperSubstantial claim

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    Interpretationcitation

    Former addicts may discount at a lower rate than current addicts because addicts with lower discount rates are better able to utilize treatment resources.

    “former addicts may discount at a lower rate than current addicts (e.g., Bickel et al., 1999) because addicts with lower discount rates are better able to utilize treatment resources (Sheffer et al., in press).”
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    Premisecitation

    Individuals who use cocaine, methamphetamine, and heroin all discount delayed reinforcers at high rates.

    “individuals that use cocaine (Bickel, Landes et al., in press; Coffey et al., 2003; Heil et al., 2006), methamphetamine (Hoffman et al., 2006), and heroin (Kirby & Petry, 2004; Madden et al., 1997) all discount delayed reinforcers at high rates.”
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    Premisecitation

    Participants with diagnoses of both substance abuse and pathological gambling exhibited the highest discounting rates, controls with no diagnosis had the lowest, and those with only pathological gambling had intermediate rates.

    “participants with diagnoses of both substance abuse and pathological gambling exhibited the highest discounting rates, lowest discounting rates were seen for controls with no diagnosis, and intermediate discounting rates were observed for those with only the diagnosis of pathological gambling.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Petry (2001b)

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    Premisecitation

    Central serotonin depletion increases discounting rates in rats, but a similar manipulation had no effect in human subjects.

    “central serotonin depletion has been shown to increase discounting rates in rats (Mobini et al., 2000), but a similar (although smaller in magnitude) manipulation had no effect in human subjects (Crean et al., 2002).”
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    Premisecitation

    Higher rates of discounting than those of healthy controls are found in individuals who already have HIV or hepatitis C.

    “higher rates of discounting than those of healthy controls are found in individuals who already have HIV (Dierst-Davies et al., 2011) or hepatitis C (Huckans et al., 2011).”
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    Premisecitation

    Ledgerwood et al. replicated the difference between discounting rates of pathological gamblers and controls, but did not observe a difference between gamblers with and without a substance abuse disorder.

    “Ledgerwood et al. (2009) replicated Petry’s (2001b) observed difference between the discounting rates of pathological gamblers and controls, but Ledgerwood et al. (2009) did not observe a difference between gamblers with and without a substance abuse disorder.”
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  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Conceptualizing excessive discounting rates as a trans-disease process may fuel the development of treatments for a range of behavioral maladies.

    “Conceptualizing excessive discounting rates as a trans-disease process may fuel the development of treatments for a range of behavioral maladies.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    McClure et al. (2004) found that choices for the smaller more immediate reinforcer were associated with relatively high levels of activation in portions of the limbic system, whereas choices for the larger later reinforcer were associated with relatively high levels of activation in areas of the prefrontal cortex.

    “They found that choices for the smaller more immediate reinforcer were associated with relatively high levels of activation in portions of the limbic system (e.g., paralimbic cortex) whereas choices for the larger later reinforcer were associated with relatively high levels of activation in areas of the prefrontal cortex (e.g., lateral prefrontal cortex, posterior parietal cortex).”
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    Premisecitation

    The executive system, consisting of the prefrontal cortices, is involved in consideration of the future and the selection of delayed rewards.

    “By contrast, the more recently developed executive system, consisting of the prefrontal cortices, is involved in consideration of the future and the selection of delayed rewards.”
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    • cites Bickel, Jarmolowicz et al., in press

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    • cites Bickel et al., 2007 source

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  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Interpretationreasoning

    The dimensional view that the CNDS view promotes may allow for increased customization of an individual's treatment.

    “Moreover, the dimensional view that the CNDS view promotes may allow for increased customization of an individual’s treatment.”
    Quote in the paperNot a substantial claim

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    Premisecitation

    Bickel et al. (2011) found that delay-discounting rates of the active training group declined while those for the control group remained unchanged.

    “Pre- and post-training measures revealed that delay-discounting rates of the active training group declined while those for the control group remained unchanged.”
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    Interpretationreasoning

    The CNDS approach suggests restoring the balance between the two competing decision systems as a new target for intervention in addiction and other behavioral patterns or disorders associated with excessive discounting.

    “Specifically, the CNDS approach suggests restoring the balance between the two competing decision systems (i.e., the impulsive and executive systems) as a new target for intervention in addiction and other behavioral patterns or disorders associated with excessive discounting.”
    Quote in the paperNot a substantial claim

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    Premisecitation

    The evidence suggests that delay discounting rate has features of a personality trait and also of a mutable, situational state.

    “In sum, the evidence regarding this issue suggests that delay discounting rate has features of a personality trait and also of a mutable (i.e., changeable), situational state (Odum, 2011).”
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    • cites Odum, 2011 source

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    Premisecitation

    Bradford (2010) found that delay-discounting rates were negatively correlated with the probability of having a recent mammogram, Pap smear, prostate examination, dental visit, cholesterol testing, flu shot usage, and rates of vigorous exercise.

    “He found that delay-discounting rates were negatively correlated with the probability of having a recent mammogram, Pap smear, prostrate examination, dental visit, cholesterol testing, flu shot usage, and rates of vigorous exercise.”
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    Interpretationreasoning

    If excessive delay discounting is a trans-disease process that is observed across a broad range of diseases, disorders and problematic behaviors, treatments that effectively treat one malady may be effective for multiple maladies.

    “If excessive delay discounting is a trans-disease process that is observed across a broad range of diseases, disorders and problematic behaviors, treatments that effectively treat one malady may be effective for multiple maladies.”
    Quote in the paperSubstantial claim

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    Premisecitation

    Elevated discounting rates have been observed in those suffering from borderline personality disorder, depression, social anxiety, and disruptive behavior disorder.

    “For example, studies have found elevated rates of discounting in those suffering from borderline personality disorder (see Bornovalova et al., 2005 for a review and discussion), depression (Yoon et al., 2007), social anxiety (Rounds et al., 2007), and disruptive behavior disorder (Swann et al., 2002).”
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    Interpretationreasoning

    CNDS theory is consistent with excessive discounting seen across a wide range of disorders and with other findings from studies using diverse measures and approaches.

    “This theory is not only consistent with excessive discounting seen across a wide range of disorders (e.g., addiction) but also with other findings from studies using diverse measures and approaches.”
    Quote in the paperSubstantial claim
32 of 32

  • The paper relies on this without support.

    Delay discounting rates are comparable across different reinforcer types and study procedures when used to infer a trans-disease process.

    “The value of this free parameter has frequently been used as a marker of within-subject (e.g., between commodities) and between-group (e.g., drug users versus non-using controls) differences.”
1 of 1

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Cites

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Research works printed but not linked: 1

  1. Bickel, W. K., Mueller, E. T. & Jarmolowicz, D. P. (in press). What is addiction? In B. McCrady & E. Epstein (Eds.), Addictions: A Comprehensive Guidebook (2nd ed.). Oxford University Press.

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Related

Authors
Bickel, W. K., Jarmolowicz, D. P., Mueller, E. T., Koffarnus, M. N., & Gatchalian, K. M.
Affiliations
  • Carilion Clinic (US)
  • Virginia Tech (US)
Corresponding author
Bickel, Warren K.
ORCID
Venue
Pharmacology & Therapeutics
Publisher
Elsevier BV
Published
2012-06
Volume
134
Issue
3
Pages
287-297
ISSN
0163-7258 (ISSN-L)
DOI
10.1016/j.pharmthera.2012.02.004
PMC
PMC3329584
OpenAlex
W2049517076
Semantic Scholar
2a130c395adb73bbda35f85b1019c7a35bf1cd81
Cited by
604
References
191
Citations by year
2026: 32 · 2025: 25 · 2024: 36 · 2023: 32 · 2022: 37 · 2021: 44 · 2020: 87 · 2019: 54 · 2018: 60 · 2017: 48 · 2016: 46 · 2015: 46 · 2014: 29 · 2013: 18 · 2012: 10
FWCI
5.74
Type
journal article
Language
en
Open access
Licence
www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations
  • Pharmacology & Therapeutics (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
NIDA (R01DA030241, R01DA024080, R01DA012997, [NIAAA] R01DA024080-02S1)
Topics
  • Social Sciences › Decision Sciences › General Decision Sciences › Decision-Making and Behavioral Economics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Neural and Behavioral Psychology Studies
  • Social Sciences › Psychology › Clinical Psychology › Gambling Behavior and Treatments
Keywords
delay discounting, addiction, substance dependence, gambling addiction, health behavior, overeating, decision-making, impulsivity
MeSH terms
Mental Disorders, Decision Making, Gambling, Humans, Impulsive Behavior, Neural Pathways, Obesity, Reinforcement, Psychology, Illicit Drugs, Time Factors, Health Behavior, Substance-Related Disorders

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