Associations between a one-shot delay discounting measure and age,income, education and real-world impulsive behavior

There has been discussion over the extent to which delay discounting – as prototypically shown by a preference for a smaller-sooner sum of money over a larger-later sum – measures the same kind of impulsive preferences that drive non-financial behavior. To address this issue, a dataset was analyzed containing 42,863 participants’ responses to a single delay-discounting choice, along with self-report behaviors that can be considered as impulsive. Choice of a smaller-sooner sum was associated with several demographics: younger age, lower income, and lower education; and impulsive behaviors: earlier age of first sexual activity and recent relationship infidelity, smoking, and higher body mass index. These findings suggest that at least an aspect of delay discounting preference is associated with a general trait influencing other forms of impulsivity, and therefore that high delay discounting is another form of impulsive behavior.     

Associations Between Delay Discounting and Risk‐Related Behaviors,Traits, Attitudes,and Outcomes

Delay discounting—preference for immediate, smaller rewards over distal, larger rewards—has been argued to be part of the “generality of deviance”, which describes the co‐occurrence of various forms of impulsive and risky behaviors among individuals. Some studies have linked laboratory‐measured delay discounting to behaviors, traits, attitudes, and outcomes associated with risk, but these associations have been inconsistent. Furthermore, many of these studies have been conducted with exclusively undergraduate samples, or in samples offering low statistical power. In a large community sample (n = 328) diverse in age and socioeconomic status, we examined associations between two measures of behavioral delay discounting (single‐shot and canonical k‐parameter estimation) and behavioral risk‐taking, personality traits associated with risk, domain‐specific risk attitudes, gambling and problem gambling, antisocial behavior, and criminal outcomes. In addition, we explored whether a novel response time latency measure of delay discounting explained variance in these risk‐related outcomes. Results indicated that behavioral delay discounting was consistently associated with all variables related to impulse control: high trait impulsivity, low trait self‐control, risk‐averse attitudes toward financial investment, risk‐prone attitudes toward gambling and health/safety risks, gambling and problem gambling, antisocial conduct, and criminal outcomes. Latency‐measured delay discounting was inconsistently associated with behavioral delay discounting and risk‐related measures. Together, results suggest that delay discounting is associated with poor impulse control consistent with a generality of deviance account. Copyright © 2016 John Wiley & Sons, Ltd.     

Impulsive choice and pre‐exposure to delays: iv. effects of delay‐ and immediacy‐exposure training relative to maturational changes in impulsivity

Impulsive choice describes preference for smaller, sooner rewards over larger, later rewards. Excessive delay discounting (i.e., rapid devaluation of delayed rewards) underlies some impulsive choices, and is observed in many maladaptive behaviors (e.g., substance abuse, gambling). Interventions designed to reduce delay discounting may provide therapeutic gains. One such intervention provides rats with extended training with delayed reinforcers. When compared to a group given extended training with immediate reinforcers, delay‐exposed rats make significantly fewer impulsive choices. To what extent is this difference due to delay‐exposure training shifting preference toward self‐control or immediacy‐exposure training (the putative control group) shifting preference toward impulsivity? The current study compared the effects of delay‐ and immediacy‐exposure training to a no‐training control group and evaluated within‐subject changes in impulsive choice across 51 male Wistar rats. Delay‐exposed rats made significantly fewer impulsive choices than immediacy‐exposed and control rats. Between‐group differences in impulsive choice were not observed in the latter two groups. While delay‐exposed rats showed large, significant pre‐ to posttraining reductions in impulsive choice, immediacy‐exposed and control rats showed small reductions in impulsive choice. These results suggest that extended training with delayed reinforcers reduces impulsive choice, and that extended training with immediate reinforcers does not increase impulsive choice.     

Impulsivity in borderline personality disorder: reward-based decision-making and its relationship to emotional distress

Impulsivity in Borderline Personality Disorder (BPD) has been defined as rapid and unplanned action. However, a preference for immediate gratification and discounting of delayed rewards might better account for the impulsive behaviors that appear to regulate emotional distress in BPD. To investigate this, a delay discounting task was administered to 30 outpatients diagnosed with BPD and 28 healthy community controls (all aged 15-24) before and after a mood induction. Trait impulsivity was measured with the Barratt Impulsiveness Scale. The results showed that the BPD group had a greater preference for immediate gratification and higher rate of discounting the delayed reward than the control group. Although the mood induction resulted in increased feelings of rejection and anger in all participants, and the rate of delay discounting changed significantly in the control group, the rate of discounting did not change for the BPD group. There was no evidence of rapid decision-making in the BPD group as response times were similar between the two groups during both trials. Finally, greater general impulsiveness and nonplanning impulsiveness were associated with greater rates of discounting in the BPD group. Together these findings suggest that BPD is characterized by a preference for immediate gratification and tendency to discount longer-term rewards. This characteristic appears to exist independent of feelings of rejection and anger, rather than being reactive to this, and to be related to trait impulsivity.     

Commitment using punishment.

Experimental parameters were adjusted so that pigeons' pairwise choices among three alternatives reflected the following order of preference: (a) a smaller-sooner reinforcer, (b) a larger-later reinforcer, and (c) the smaller-sooner reinforcer followed by a punishment (consisting of an extended blackout period). After this order of preference was established, the pigeons were exposed to a two-link, concurrent-chain-like choice procedure. One terminal link consisted of a choice between the smaller-sooner and the larger-later reinforcer; the other terminal link was identical to the first except that the smaller-sooner reinforcer was followed by blackout punishment. The pigeons' preference (in their initial-link choice) for the terminal link with the punished smaller-sooner alternative increased as the delay between the initial and terminal links increased. By choosing this terminal link, the pigeons are said to have "committed" themselves to obtaining the larger-later reinforcer. However, unlike prior studies of commitment (e.g., Rachlin & Green, 1972), it was still possible after making the commitment for the pigeons to choose the smaller-sooner reinforcer and undergo the punishment. The pigeons did in fact occasionally make this highly deleterious choice.     

Delay discounting of different outcomes: Review and theory

Steep delay discounting is characterized by a preference for small immediate outcomes relative to larger delayed outcomes and is predictive of drug abuse, risky sexual behaviors, and other maladaptive behaviors. Nancy M. Petry was a pioneer in delay discounting research who demonstrated that people discount delayed monetary gains less steeply than they discount substances with abuse liability. Subsequent research found steep discounting for not only drugs, but other nonmonetary outcomes such as food, sex, and health. In this systematic review, we evaluate the hypotheses proposed to explain differences in discounting as a function of the type of outcome and explore the trait- and state-like nature of delay discounting. We found overwhelming evidence for the state-like quality of delay discounting: Consistent with Petry and others' work, nonmonetary outcomes are discounted more steeply than monetary outcomes. We propose two hypotheses that together may account for this effect: Decreasing Future Preference and Decreasing Future Worth. We also found clear evidence that delay discounting has trait-like qualities: People who steeply discount monetary outcomes steeply discount nonmonetary outcomes as well. The implication is that changing delay discounting for one outcome could change discounting for other outcomes.     

Delay, Probability, and Social Discounting in A Public Goods Game

A human social discount function measures the value to a person of a reward to another person at a given social distance. Just as delay discounting is a hyperbolic function of delay, and probability discounting is a hyperbolic function of odds-against, social discounting is a hyperbolic function of social distance. Experiment 1 obtained individual social, delay, and probability discount functions for a hypothetical $75 reward; participants also indicated how much of an initial $100 endowment they would contribute to a common investment in a public good. Steepness of discounting correlated, across participants, among all three discount dimensions. However, only social and probability discounting were correlated with the public-good contribution; high public-good contributors were more altruistic and also less risk averse than low contributors. Experiment 2 obtained social discount functions with hypothetical $75 rewards and delay discount functions with hypothetical $1,000 rewards, as well as public-good contributions. The results replicated those of Experiment 1; steepness of the two forms of discounting correlated with each other across participants but only social discounting correlated with the public-good contribution. Most participants in Experiment 2 predicted that the average contribution would be lower than their own contribution.     

Altering Impulsive Decision Making With an Acceptance-Based Procedure

Delay discounting is one facet of impulsive decision making and involves subjectively devaluing a delayed outcome. Steeply discounting delayed rewards is correlated with substance abuse and other problematic behaviors. To the extent that steep delay discounting underlies these clinical disorders, it would be advantageous to find psychosocial avenues for reducing delay discounting. Acceptance-based interventions may prove useful as they may help to decrease the distress that arises while waiting for a delayed outcome. The current study was conducted to determine if a 60–90 minute acceptance-based training would change delay discounting rates among 30 undergraduate university students in comparison to a waitlist control. Measures given at pre- and posttraining included a hypothetical monetary delay discounting task, the Acceptance and Action Questionnaire-II (AAQ-II), and the Distress Tolerance Scale. Those assigned to the treatment group decreased their discounting of delayed money, but not distress intolerance or psychological inflexibility when compared to the waitlist control group. After the waiting period, the control group received the intervention. Combining all participants’ pre- to posttreatment data, the acceptance-based treatment significantly decreased discounting of monetary rewards and increased distress tolerance. The difference in AAQ-II approached significance. Acceptance-based treatments may be a worthwhile option for decreasing delay discounting rates and, consequently, affecting the choices that underlie addiction and other problematic behaviors.     

Positive mood effects on delay discounting

Delay discounting is the process by which the value of an expected reward decreases as the delay to obtaining that reward increases. Individuals with higher discounting rates tend to prefer smaller immediate rewards over larger delayed rewards. Previous research has indicated that personality can influence an individual's discounting rates, with higher levels of Extraversion predicting a preference for immediate gratification. The current study examined how this relationship would be influenced by situational mood inductions. While main effects were observed for both Extraversion and cognitive ability in the prediction of discounting rates, a significant interaction was also observed between Extraversion and positive affect. Extraverted individuals were more likely to prefer an immediate reward when first put in a positive mood. Extraverts thus appear particularly sensitive to impulsive, incentive-reward-driven behavior by temperament and by situational factors heightening positive affect.     

Age‐related differences in delay discounting: Immediate reward,reward magnitude,and social influence

Delay discounting refers to the tendency of individuals to subjectively devalue rewards that are to be received in the future, with high rates of delay discounting being associated with a variety of maladaptive life outcomes (e.g., unhealthy dietary and exercise behaviors). The current study explored the psychological and social processes involved in adult age‐related differences in delay discounting of monetary rewards. Younger adults exhibited higher levels of delay discounting than older adults. This increased level of patience in older adults was found whether smaller‐sooner rewards were to be received immediately or in the future. However, there was an interaction with reward magnitude, whereby younger adults exhibited higher levels of delay discounting for smaller reward magnitudes but not larger reward magnitudes. Social influence on delay discounting was investigated by having participants complete three phases of the delay‐discounting task: an individual precollaboration phase, a collaboration phase in age‐group‐matched dyads, and an individual postcollaboration phase. A convergence effect was observed in that dyad members' postcollaboration choices were significantly more similar compared to their baseline choices during the precollaboration phase. Moreover, levels of convergence were comparable between younger and older adults, suggesting age invariance in social influence on delay discounting. The current results demonstrate a degree of malleability in delay discounting that extends into older adulthood, making interventions targeting the construct a promising avenue for future research.     

Adolescents' performance on delay and probability discounting tasks: contributions of age, intelligence, executive functioning, and self-reported externalizing behavior

Healthy adolescents, ages 9-23, completed delay and probability discounting tasks and measures of verbal and nonverbal intelligence, executive functioning, and self-reported internalizing and externalizing behavior. Delay but not probability discounting decreased with age. Delay discounting was also associated with verbal intelligence and Go-NoGo and Iowa Gambling Task performance. Probability discounting was associated only with externalizing behavior. Findings conform to an accumulation of evidence that while delay and probability discounting may have some overlapping components, they also reflect some fundamentally different processes in this age group.     

The neural mechanisms of inter-temporal decision-making: understanding variability

Humans and animals prefer immediate over delayed rewards (delay discounting). This preference for smaller-but-sooner over larger-but-later rewards shows substantial interindividual variability in healthy subjects. Moreover, a strong bias towards immediate reinforcement characterizes many psychiatric conditions such as addiction and attention-deficit hyperactivity disorder. We discuss the neural mechanisms underlying delay discounting and describe how interindividual variability (trait effects) in the neural instantiation of subprocesses of delay discounting (such as reward valuation, cognitive control and prospection) contributes to differences in behaviour. We next discuss different interventions that can partially remedy impulsive decision-making (state effects). Although the precise neural mechanisms underlying many of these modulating influences are only beginning to be unravelled, they point towards novel treatment approaches for disorders of impulse control.     

Delay discounting in Lewis and Fischer 344 rats: steady-state and rapid-determination adjusting-amount procedures

Lewis rats have been shown to make more impulsive choices than Fischer 344 rats in discrete-trial choice procedures that arrange fixed (i.e., nontitrating) reinforcement parameters. However, nontitrating procedures yield only gross estimates of preference, as choice measures in animal subjects are rarely graded at the level of the individual subject. The present study was designed to examine potential strain differences in delay discounting using an adjusting-amount procedure, in which distributed (rather than exclusive) choice is observed due to dynamic titration of reinforcer magnitude across trials. Using a steady-state version of the adjusting-amount procedure in which delay was manipulated between experimental conditions, steeper delay discounting was observed in Lewis rats compared to Fischer 344 rats; further, delay discounting in both strains was well described by the traditional hyperbolic discounting model. However, upon partial completion of the present study, a study published elsewhere (Wilhelm & Mitchell, 2009) demonstrated no difference in delay discounting between these strains with the use of a more rapid version of the adjusting-amount procedure (i.e., in which delay is manipulated daily). Thus, following completion of the steady-state assessment in the present study, all surviving Lewis and Fischer 344 rats completed an approximation of this rapid-determination procedure in which no strain difference in delay discounting was observed.     

Comparison of delay discounting of different outcomes in cigarette smokers,smokeless tobacco users,e-cigarette users,and non-tobacco users

Delay discounting is the process by which a commodity loses value as the delay to its receipt increases. Rapid discounting predicts various maladaptive behaviors including tobacco use. Typically, delay discounting of different outcomes has been compared between cigarette smokers and nonsmokers. To better understand the relationship of delay discounting to different modes of tobacco use, we examined the differences in delay discounting of different outcomes between cigarette smokers, smokeless tobacco users, e-cigarette users, and non-tobacco users. In the present study, all participants completed 8 titrating delay-discounting tasks: $100 gain, $500 gain, $500 loss, alcohol, entertainment, food, a temporary health gain, and a temporary cure from a disease. Non-tobacco users discounted most outcomes less than tobacco users overall; however, there were no differences in discounting among the different types of tobacco users. These results suggest that nicotine consumption of any kind is associated with a higher degree of impulsivity compared to non-tobacco users. Adoption of tobacco products that have been perceived as less harmful (e.g., e-cigarettes) is not associated with a baseline difference or decrease in delay discounting if adopted after a history of cigarette use.     

Building blocks of self-control: increased tolerance for delay with bundled rewards

Impulsive choice can be defined as temporary preference for a smaller-sooner reward (SS) over a larger-later reward (LL). Hyperbolic discounting implies that impulsive choices will occur less when organisms choose between a series of SSs versus LLs all at once than when they choose between single SS versus LL pairs. Eight rats were exposed to two conditions of an intertemporal choice paradigm using sucrose solution as reward. In both conditions, the LL was 150 microl delayed by 3 s, while the SS was an immediate reward that ranged from 25-150 microl across sessions. Preference for the LL was greater when the chosen reward was automatically delivered three times in succession (bundled) than when it was chosen singly and delivered after each choice. For each of the 8 rats, the estimated SS amount that produced indifference was higher in the bundled condition than in the single condition. Because bundling in humans may be based on the perception that one's current choice is predictive of future choices, the data presented here may demonstrate an important building block of self-control.     

Comparisons of women with high and low trait impulsivity using behavioral models of response-disinhibition and reward-choice

Two types of behavioral models of impulsive behavior, response-disinhibition/attentional and reward-choice response models, were used to compare women grouped by high (Impulse+, n=43) and low (Impulse−, n=43) self-reported impulsive behavior on the Eysenck I₇ Questionnaire. Two of the four different tasks tested were response-disinhibition/attentional models; these included the Immediate and Delayed Memory Task and the GoStop Task. The other two tasks were based on the reward-choice model of impulsivity and included the Single Key Impulsivity Paradigm and the Two-Choice Reward Task. Of particular interest was whether commission errors (response-disinhibition/attentional paradigms) or a preference for smaller–sooner rewards over larger–later rewards (reward-choice) would differ between the groups. Participants completed one session of each task in a single day. The most significant findings were that the Impulse+ group had: (1) elevated commission errors; (2) lower stimulus discriminability (between target and catch stimuli); and (3) poorer response inhibition to a stop signal. Responding on the response-disinhibition/attentional tasks distinguished between the impulsivity groups while the reward-choice tasks did not. These results demonstrate that women who report higher levels of trait impulsivity respond in a manner consistent with previous studies examining impulsive behavior.     

Changes in intertemporal choices in deviant behaviors

Delay discounting is the process of devaluing results that happen in the future. We present a comprehensive literature review of changes on intertemporal choices in deviant behaviors, namely in (a) substance-related and addictive disorders, (b) disruptive, impulse-control, and conduct disorders, and (c) eating disorders. We also present studies focused on differences in demographic characteristics of the populations by gender, age, and education/social class. Delay discounting is presented as a process of studying intertemporal choices, resulting from decades of empirical research. Studies indicate that this process may provide explanation as to why individuals will sometimes choose a smaller reward, available sooner, instead of a larger reward available later. When studying populations with the above-mentioned problems, they tend to exhibit more pronounced discounting functions than control groups. The association between discounting and gender is not clear. The relationship between delay discounting and age is relatively clear, where older individuals discount less markedly than younger individuals. Studies suggest that shallower discounting gradients are associated with higher levels of intelligence and academic success. We emphasize the need for more empirical research on delay discounting, especially in regard to deviant behavior that may be associated with impulse-control disorders.     

Personal relative deprivation, delay discounting, and gambling

Several lines of research have provided evidence for a relation between personal relative deprivation and gambling. Despite this knowledge, little is known about possible psychological mechanisms through which personal relative deprivation exerts its influence on gambling. The authors of this research sought to examine one such mechanism: the desire for immediate rewards. Using complementary approaches to studying psychological mechanisms, they tested in four studies the general hypothesis that personal relative deprivation translates into gambling urges and behavior in part via increased desires for immediate, even if smaller, rewards. Study 1 showed that an experimental manipulation of personal relative deprivation increased participants' preferences for smaller-sooner over larger-later rewards during a delay-discounting task. Studies 2 and 3 showed that a decreased willingness to delay gratification led to increased gambling behavior. Study 4 showed that preferences for smaller-sooner over larger-later rewards statistically mediated the relation between self-reported personal relative deprivation and gambling urges among a community sample of gamblers. The implications and potential applications of these findings are discussed.     

Sex differences in the effects of disinhibition,perceived peer drinking,and delay discounting on drinking among Japanese college students

Disinhibition, perceived peer drinking, and delay discounting are considered significant predictors of drinking in young adults. This study examined whether perceived peer drinking and delay discounting mediate the association between disinhibition and drinking for young men and women. In this study, 258 Japanese college students (109 men and 149 women, mean age 19.17 (SD = 1.20) years old) completed a self-administered questionnaire that included four measures—the disinhibition subscale of the Sensation Seeking Scale for Japanese Adolescents, the proportion of friends who drink as an index of perceived peer drinking behaviors, the Monetary Choice Questionnaire, and participants’ own drinking behavior. In the multiple mediator models analyzed using structural equation modeling, for both sexes, perceived peer drinking had the largest direct effect on participants’ drinking, followed by disinhibition and delay discounting. However, the results of mediation analyses indicated that perceived peer drinking mediated the association between disinhibition and drinking for only women. The results of this study imply that it is important to consider sex differences in the association between personality traits and peer influence to develop programs aiming to reduce drinking among young adults in Japan.     

Measurement of Impulsivity: Construct Coherence, Longitudinal Stability, and Relationship with Externalizing Problems in Middle Childhood and Adolescence

This study focused on the assessment of impulsivity in nonreferred school-aged children. Children had been participants since infancy in the Bloomington Longitudinal Study. Individual differences in impulsivity were assessed in the laboratory when children were 6 (44 boys, 36 girls) and 8 (50 boys, 39 girls) years of age. Impulsivity constructs derived from these assessments were related to parent and teacher ratings of externalizing problems across the school-age period (ages 7–10) and to parent and self-ratings of these outcomes across adolescence (ages 14–17). Consistent with prior research, individual measures of impulsivity factor-analyzed into subdimensions reflecting children's executive control capabilities, delay of gratification, and ability or willingness to sustain attention and compliance during work tasks. Children's performance on the main interactive task index, inhibitory control, showed a signficant level of stability between ages 6 and 8. During the school-age years, children who performed impulsively on the laboratory measures were perceived by mothers and by teachers as more impulsive, inattentive, and overactive than others, affirming the external validity of the impulsivity constructs. Finally, impulsive behavior in the laboratory at ages 6 and 8 predicted maternal and self-ratings of externalizing problem behavior across adolescence, supporting the longterm predictive value of the laboratory-derived impulsivity measures.