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result(s) for
"Discounting"
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Steep discounting of delayed monetary and food rewards in obesity: a meta-analysis
2016
An increasing number of studies have investigated delay discounting (DD) in relation to obesity, but with mixed findings. This meta-analysis synthesized the literature on the relationship between monetary and food DD and obesity, with three objectives: (1) to characterize the relationship between DD and obesity in both case-control comparisons and continuous designs; (2) to examine potential moderators, including case-control v. continuous design, money v. food rewards, sample sex distribution, and sample age (18 years); and (3) to evaluate publication bias.
From 134 candidate articles, 39 independent investigations yielded 29 case-control and 30 continuous comparisons (total n = 10 278). Random-effects meta-analysis was conducted using Cohen's d as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger tests, meta-regression of publication year and effect size, and imputation of missing studies.
The primary analysis revealed a medium effect size across studies that was highly statistically significant (d = 0.43, p < 10-14). None of the moderators examined yielded statistically significant differences, although notably larger effect sizes were found for studies with case-control designs, food rewards and child/adolescent samples. Limited evidence of publication bias was present, although the Begg-Mazumdar test and meta-regression suggested a slightly diminishing effect size over time.
Steep DD of food and money appears to be a robust feature of obesity that is relatively consistent across the DD assessment methodologies and study designs examined. These findings are discussed in the context of research on DD in drug addiction, the neural bases of DD in obesity, and potential clinical applications.
Journal Article
Behavioral trainings and manipulations to reduce delay discounting: A systematic review
by
Scheres, Anouk
,
Graf, Uta
,
Scholten, Hanneke
in
Behavioral Science and Psychology
,
Cognitive Behavioral Therapy
,
Cognitive Psychology
2019
In everyday decision-making, individuals make trade-offs between short-term and long-term benefits or costs. Depending on many factors, individuals may choose to wait for larger delayed reward, yet in other situations they may prefer the smaller, immediate reward. In addition to within-subject variation in the short-term versus long-term reward trade-off, there are also interindividual differences in delay discounting (DD), which have been shown to be quite stable. The extent to which individuals discount the value of delayed rewards turns out to be associated with important health and disorder-related outcomes: the more discounting, the more unhealthy or problematic choices. This has led to the hypothesis that DD can be conceptualized as trans-disease process. The current systematic review presents an overview of behavioral trainings and manipulations that have been developed to reduce DD in human participants aged 12 years or older. Manipulation studies mostly contain one session and measure DD directly after the manipulation. Training studies add a multiple session training component that is not per se related to DD, in between two DD task measurements. Ninety-eight studies (151 experiments) were identified that tested behavioral trainings and manipulations to decrease DD. Overall, results indicated that DD can be decreased, showing that DD is profoundly context dependent and changeable. Most promising avenues to pursue in future research seem to be acceptance-based/mindfulness-based trainings, and even more so manipulations involving a future orientation. Limitations and recommendations are discussed to identify the mechanistic processes that allow for changes in discount rate and behavior accordingly.
Journal Article
Validation of the Sexual Discounting Task for Use in Adolescents
by
Harris, Bethany
,
Ramos, Ashley
,
Johnson, Matthew W.
in
Adolescent
,
Adolescent Behavior - psychology
,
Adolescent girls
2024
The Sexual Discounting Task (SDT) was developed to evaluate the effects of delay on decision making as it relates to sexual risk-taking behaviors. Though previously validated with other populations, including urban emerging adults, the current study sought to validate the SDT with adolescents. A sample of adolescents (
N
= 155; 61% female) between ages 14 and 21 (
M
age
= 19.5 years) was recruited to complete the SDT (involving choices between immediate unprotected sex and delayed sex with a condom with hypothetical sexual partners) and the Delay Discounting Task (a delay discounting task for money outcomes). Additionally, they completed several self-report measures assessing demographics, sexual behavior, and sexual history. If the condom was readily available, respondents were more likely to use a condom for partners who were judged “most likely to have an STI” and for those that participants were “least likely to have sex with.” Moreover, when a condom was not immediately available, greater self-reported sexual risk-taking was related to greater sexual discounting (i.e., greater effects of delay on decreasing condom use). Furthermore, sexual discounting was greater among partners deemed more desirable and those judged “least likely to have an STI.” Differences in sexual discounting were significant after controlling for immediately available condom use. Findings from the current study suggest that the SDT is clinically meaningful for adolescents and is sensitive to factors that influence real-world decisions to use condoms. Future treatment and prevention should consider delay discounting as an important variable affecting sexual risk behavior.
Journal Article
Can delay discounting deliver on the promise of RDoC?
2019
The National Institute of Mental Health launched the Research Domain Criteria (RDoC) initiative to better understand dimensions of behavior and identify targets for treatment. Examining dimensions across psychiatric illnesses has proven challenging, as reliable behavioral paradigms that are known to engage specific neural circuits and translate across diagnostic populations are scarce. Delay discounting paradigms seem to be an exception: they are useful for understanding links between neural systems and behavior in healthy individuals, with potential for assessing how these mechanisms go awry in psychiatric illnesses. This article reviews relevant literature on delay discounting (or the rate at which the value of a reward decreases as the delay to receipt increases) in humans, including methods for examining it, its putative neural mechanisms, and its application in psychiatric research. There exist rigorous and reproducible paradigms to evaluate delay discounting, standard methods for calculating discount rate, and known neural systems probed by these paradigms. Abnormalities in discounting have been associated with psychopathology ranging from addiction (with steep discount rates indicating relative preference for immediate rewards) to anorexia nervosa (with shallow discount rates indicating preference for future rewards). The latest research suggests that delay discounting can be manipulated in the laboratory. Extensively studied in cognitive neuroscience, delay discounting assesses a dimension of behavior that is important for decision-making and is linked to neural substrates and to psychopathology. The question now is whether manipulating delay discounting can yield clinically significant changes in behavior that promote health. If so, then delay discounting could deliver on the RDoC promise.
Journal Article
On Four Types of Devaluation of Outcomes Due to Their Costs: Delay, Probability, Effort, and Social Discounting
2019
Discounting refers to decreases in the subjective value of an outcome with increases in some attribute of that outcome. The attributes most commonly studied are delay and probability, with far less research on effort and social discounting. Although these attributes all represent costs that reduce subjective value, it is as yet unclear how the extent to which they do so is related at the individual level. Accordingly, the present study examined the degree to which individual participants discounted hypothetical monetary rewards on each of four discounting tasks in which the delay, probability, effort, and number of people with whom the money was to be shared were manipulated. At the group level, larger amounts were discounted less steeply than smaller amounts when delay and effort were varied, whereas larger amounts were discounted more steeply when probability and number of people were varied. At the individual level, the correlational pattern was examined using exploratory factor analysis. A six-factor structure (with separate factors for delay and effort, and two factors each for social and probability discounting) described the relations among indifference points. At a more molar level, a two-factor structure, which corresponded to the direction of the observed magnitude effects, described the relations among area-under-the-curve measures of discounting in the eight conditions resulting from crossing two monetary amounts with the four cost factors. We conclude that despite sharing some similarities, individual and group differences in discounting involving the different types of costs reflect mostly separate processes and traits.
Journal Article
Neural substrates of impulsive decision making modulated by modafinil in alcohol-dependent patients
2014
Impulsive decision making is a hallmark of frequently occurring addiction disorders including alcohol dependence (AD). Therefore, ameliorating impulsive decision making is a promising target for the treatment of AD. Previous studies have shown that modafinil enhances cognitive control functions in various psychiatric disorders. However, the effects of modafinil on delay discounting and its underlying neural correlates have not been investigated as yet. The aim of the current study was to investigate the effects of modafinil on neural correlates of impulsive decision making in abstinent AD patients and healthy control (HC) subjects.
A randomized, double-blind, placebo-controlled, within-subjects cross-over study using functional magnetic resonance imaging (fMRI) was conducted in 14 AD patients and 16 HC subjects. All subjects participated in two fMRI sessions in which they either received a single dose of placebo or 200 mg of modafinil 2 h before the session. During fMRI, subjects completed a delay-discounting task to measure impulsive decision making.
Modafinil improved impulsive decision making in AD pateints, which was accompanied by enhanced recruitment of frontoparietal regions and reduced activation of the ventromedial prefrontal cortex. Moreover, modafinil-induced enhancement of functional connectivity between the superior frontal gyrus and ventral striatum was specifically associated with improvement in impulsive decision making.
These findings indicate that modafinil can improve impulsive decision making in AD patients through an enhanced coupling of prefrontal control regions and brain regions coding the subjective value of rewards. Therefore, the current study supports the implementation of modafinil in future clinical trials for AD.
Journal Article
Moderate Stability among Delay, Probability, and Effort Discounting in Humans
by
Santoyo, Carlos
,
Mitchell, Suzanne H
,
Escobar, Gisel G
in
Discounting
,
Mathematical functions
,
Probability
2023
The stability of delay discounting across time has been well-established. However, limited research has examined the stability of probability discounting, and no studies of the stability of effort discounting are available. The present study assessed the steady-state characteristics of delay, probability, and effort discounting tasks across time with hypothetical rewards in humans, as well as whether response characteristics suggested a common discounting equation. Participants completed delay, probability, and effort discounting tasks on three occasions. We found moderate relative stability of delay and probability tasks, and similar evidence for absolute stability across time for all tasks. The interclass correlations coefficient showed some correspondence across time points and tasks, and higher levels of between subject variability, especially for the effort discounting task, suggesting trait level variables has a stronger influence on performance than state level variables. Performance on the delay and probability tasks were moderately correlated and similar mathematical functions fit choice patterns on both tasks (hyperbolic), suggesting that delay and probability discounting processes shared some common elements. Lower correlations and different function fits suggested that effort discounting involves more unique features.
Journal Article
Enhancement in dopamine reduces generous behaviour in women
by
Burrasch, Caroline
,
Münte, Thomas F.
,
Strang, Sabrina
in
Agonists
,
Biology and Life Sciences
,
Blindness
2019
Generosity is a human behavior common in social contexts. However, humans are not equally generous to everyone alike. Instead, generosity decreases as a function of social distance, an effect called social discounting. Studies show that such social discounting effect depends on diverse factors including personality traits, cultures, stress or hormonal levels. Recently, the importance of the neurotransmitter dopamine in regulating social interactions has been highlighted. However, it remains unclear how exactly dopamine agonist administration modulates generous behavior as a function of social discounting. Here, we investigate the causal effect of dopamine agonist administration on social discounting in a pharmacological intervention study. We employ a randomized, double-blind, within-subject design to investigate the impact of the D2/D3 receptor agonist pramipexole on social discounting by keeping gender constant. We apply hyperbolic social discount model to the data and provide evidence that women under pramipexole become less generous in general, especially towards close others. Our results highlight the crucial role of dopamine in social decision making.
Journal Article
Approaching future rewards or waiting for them to arrive: Spatial representations of time and intertemporal choice
by
Spence, Alexa
,
Houghton, Robert
,
Fletcher, Daniel
in
Analysis
,
Cognition
,
Delay Discounting - physiology
2024
Our mental representation of the passage of time is structured by concepts of spatial motion, including an ego-moving perspective in which the self is perceived as approaching future events and a time-moving perspective in which future events are perceived as approaching the self. While previous research has found that processing spatial information in one’s environment can preferentially activate either an ego-moving or time-moving temporal perspective, potential downstream impacts on everyday decision-making have received less empirical attention. Based on the idea people may feel closer to positive events they see themselves as actively approaching rather than passively waiting for, in this pre-registered study we tested the hypothesis that spatial primes corresponding to an ego-moving (vs. time-moving) perspective would attenuate temporal discounting by making future rewards feel more proximal. 599 participants were randomly assigned to one of three spatial prime conditions (ego-moving, time-moving, control) resembling map-based tasks people may engage with on digital devices, before completing measures of temporal perspective, perceived wait time, perceived control over time, and temporal discounting. Partly consistent with previous research, the results indicated that the time-moving prime successfully activated the intended temporal perspective–though the ego-moving prime did not. Contrary to our primary hypotheses, the spatial primes had no effect on either perceived wait time or temporal discounting. Processing spatial information in a map-based task therefore appears to influence how people conceptualise the passage of time, but there was no evidence for downstream effects on intertemporal preferences. Additionally, exploratory analysis indicated that greater perceived control over time was associated with lower temporal discounting, mediated by a reduction in perceived wait time, suggesting a possible area for future research into individual differences and interventions in intertemporal decision-making.
Journal Article