Differences in Discounting Behavior and Brain Responses for Food and Money Reward.

Most neuroeconomic research seeks to understand how value influences decision-making. The influence of reward type is less well understood. We used functional magnetic resonance imaging (fMRI) to investigate delay discounting of primary (i.e., food) and secondary rewards (i.e., money) in 28 healthy, normal-weighted participants (mean age = 26.77; 18 females). To decipher differences in discounting behavior between reward types, we compared how well-different option-based statistical models (exponential, hyperbolic discounting) and attribute-wise heuristic choice models (intertemporal choice heuristic, dual reasoning and implicit framework theory, trade-off model) captured the reward-specific discounting behavior. Contrary to our hypothesis of different strategies for different rewards, we observed comparable discounting behavior for money and food (i.e., exponential discounting). Higher k values for food discounting suggest that individuals decide more impulsive if confronted with food. The fMRI revealed that money discounting was associated with enhanced activity in the right dorsolateral prefrontal cortex, involved in executive control; the right dorsal striatum, associated with reward processing; and the left hippocampus, involved in memory encoding/retrieval. Food discounting, instead, was associated with higher activity in the left temporoparietal junction suggesting social reinforcement of food decisions. Although our findings do not confirm our hypothesis of different discounting strategies for different reward types, they are in line with the notion that reward types have a significant influence on impulsivity with primary rewards leading to more impulsive choices.

Approaching future rewards or waiting for them to arrive: Spatial representations of time and intertemporal choice.

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.

Child inhibited temperament and caregiver distraction encouragement jointly predict children's delay of gratification competencies.

A cool attentional focus during the classic delay of gratification (DG) task involves shifting attention away from the emotion-arousing features and is a key mechanism that underlies children's ability to resist temptation and wait. Yet, we know relatively little about what gives rise to individual differences in cool focus in the first place. The current study (N = 162, Mage = 6.86 years) addressed this question by focusing on key aspects of child temperament (i.e., behavioral inhibition, BI) and caregiver emotion socialization (i.e., distraction encouragement) as joint predictors of cool focus. We theorized that because children are left alone in an unfamiliar environment for an undefined duration, the DG task would be especially taxing for children higher in BI, hindering their ability to deploy a cool focus and wait. We also reasoned that caregiver encouragement of distraction would serve as a protective factor by allowing children higher in BI to more easily activate a cool focus even when experiencing a taxing task. Results were partially consistent with these hypotheses, shedding new light on precursors to a central ingredient of DG ability.

Developmental deviation in delay discounting as a transdiagnostic indicator of risk for child psychopathology.

BACKGROUND: The tendency to prefer smaller, immediate rewards over larger, delayed rewards is known as delay discounting (DD). Developmental deviations in DD may be key in characterizing psychiatric and neurodevelopmental disorders. Recent work empirically supported DD as a transdiagnostic process in various psychiatric disorders. Yet, there is a lack of research relating developmental changes in DD from mid-childhood to adolescence to psychiatric and neurodevelopmental disorders. Additionally, examining the interplay between socioeconomic status/total household income (THI) and psychiatric symptoms is vital for a more comprehensive understanding of pediatric pathology and its complex relationship with DD. METHODS: The current study addresses this gap in a robust psychiatric sample of 1843 children and adolescents aged 5-18 (M = 10.6, SD = 3.17; 1,219 males, 624 females). General additive models (GAMs) characterized the shape of age-related changes in monetary and food reward discounting for nine psychiatric disorders compared with neurotypical youth (NT; n = 123). Over 40% of our sample possessed a minimum of at least three psychiatric or neurodevelopmental disorders. We used bootstrap-enhanced Louvain community detection to map DD-related comorbidity patterns. We derived five subtypes based on diagnostic categories present in our sample. DD patterns were then compared across each of the subtypes. Further, we evaluated the effect of cognitive ability, emotional and behavioral problems, and THI in relation to DD across development. RESULTS: Higher discounting was found in six of the nine disorders we examined relative to NT. DD was consistently elevated across development for most disorders, except for depressive disorders, with age-specific DD differences compared with NTs. Community detection analyses revealed that one comorbidity subtype consisting primarily of Attention-Deficit/Hyperactivity Disorder (ADHD) Combined Presentation and anxiety disorders displayed the highest overall emotional/behavioral problems and greater DD for the food reward. An additional subtype composed mainly of ADHD, predominantly Inattentive Presentation, learning, and developmental disorders, showed the greatest DD for food and monetary rewards compared with the other subtypes. This subtype had deficits in reasoning ability, evidenced by low cognitive and academic achievement performance. For this ADHD-I and developmental disorders subtype, THI was related to DD across the age span such that participants with high THI showed no differences in DD compared with NTs. In contrast, participants with low THI showed significantly worse DD trajectories than all others. Our results also support prior work showing that DD follows nonlinear developmental patterns. CONCLUSIONS: We demonstrate preliminary evidence for DD as a transdiagnostic marker of psychiatric and neurodevelopmental disorders in children and adolescents. Comorbidity subtypes illuminate DD heterogeneity, facilitating the identification of high-risk individuals. Importantly, our findings revealed a marked link between DD and intellectual reasoning, with children from lower-income households exhibiting lower reasoning skills and heightened DD. These observations underscore the potential consequences of compromised self-regulation in economically disadvantaged individuals with these disorders, emphasizing the need for tailored interventions and further research to support improved outcomes.

Evidence accumulation is not essential for generating intertemporal preference: A comparison of dynamic cognitive models of matching tasks.

Intertemporal preference has been investigated mainly with a choice paradigm. However, a matching paradigm might be more informative for a proper inference about intertemporal preference and a deep understanding of the underlying cognitive mechanisms. This research involved two empirical studies using the matching paradigm and compared various corresponding dynamic models. These models were developed under either the framework of decision field theory, an exemplar theory assuming evidence accumulation, or a non-evidence-accumulation framework built upon the well-established notions of random utility and discrimination threshold (i.e., the RUDT framework). Most of these models were alternative-based whereas the others were attribute-based ones. Participants in Study 1 were required to fill in the amount of an immediate stimulus to make it as attractive as a delayed stimulus, whereas those in Study 2 needed to accomplish a more general matching task in which either the payoff amount or delay length of one stimulus was missing. Consistent behavioral regularities regarding both matching values and response times were revealed in these studies. The results of model comparison favored in general the RUDT framework as well as an attribute-based perspective on intertemporal preference. In addition, the predicted matching values and response times of the best RUDT model were also highly correlated with the observed data and replicated most observed behavioral regularities. Together, this research and previous modeling work on intertemporal choice suggest that evidence accumulation is not essential for generating intertemporal preference. Future research should examine the validity of the new framework in other preferential decisions for a more stringent test of the framework.

The Phenotype of Recovery X: Associations between delay discounting, regulatory flexibility, and remission from substance use disorder.

INTRODUCTION: Delay discounting (DD) and self-regulation are important predictors of substance use disorder (SUD) outcomes. Further, regulatory flexibility (RF; i.e., selecting, monitoring, and adapting coping techniques based on contextual demands) is related to psychological resilience. However, studies have yet to examine associations among DD, RF, and remission from SUDs among individuals in recovery. METHODS: Individuals (N = 148) in SUD recovery completed the Context Sensitivity Index (CSI), the Flexible Regulation of Emotional Expression (FREE) Scale, and the Perceived Ability to Cope with Trauma (PACT) Scale to assess RF and, an $1000 hypothetical reward Adjusting Amount Delay Discounting Task. The study considered individuals to be in remission from SUD if they did not endorse any SUD DSM-5 symptom other than craving (except tobacco use disorder) in the past three months. The study team used t-tests to examine differences in RF and DD by remission status. Univariate linear regressions were used to examine the relationship between RF and DD. Finally, mediation models examined the dynamic relationship among DD, RF, and remission status. RESULTS: Remitted individuals (n = 82) had significantly lower DD (i.e., greater preference for larger, later rewards) rates (p < .001) and higher context sensitivity (p < .001) and coping flexibility (p < .001). The study found significant negative associations between DD and context sensitivity (p = .008), coping flexibility (p = .002), and emotion regulation flexibility (p < .001). Finally, context sensitivity (p = .023) and coping flexibility (p = .009) mediated the relationship between DD and SUD remission. CONCLUSIONS: Results suggest that individuals in recovery with broader temporal windows can better identify contextual demands and flexibly cope, contributing to improved SUD recovery outcomes.

Sex differences in atypical fronto-subcortical structural connectivity among children with attention-deficit/hyperactivity disorder: Associations with delay discounting.

PURPOSE: Atypical fronto-subcortical neural circuitry has been implicated in the pathophysiology of attention-deficit/hyperactivity disorder (ADHD), including connections between prefrontal cortical regions involved in top-down cognitive control and subcortical limbic structures (striatum and amygdala) involved in bottom-up reward and emotional processing. The integrity of fronto-subcortical connections may also relate to interindividual variability in delay discounting, or a preference for smaller, immediate over larger, delayed rewards, which is associated with ADHD, with recent evidence of ADHD-related sex differences. METHODS: We applied diffusion tensor imaging to compare the integrity of the white matter connections within fronto-subcortical tracts among 187 8-12 year-old children either with ADHD ((n = 106; 29 girls) or typically developing (TD) controls ((n = 81; 28 girls). Analyses focused on diagnostic group differences in fractional anisotropy (FA) within fronto-subcortical circuitry implicated in delay discounting, connecting subregions of the striatum (dorsal executive and ventral limbic areas) and amygdala with prefrontal regions of interest (dorsolateral [dlPFC], orbitofrontal [OFC] and anterior cingulate cortex [ACC]), and associations with two behavioral assessments of delay discounting. RESULTS: Children with ADHD showed reduced FA in tracts connecting OFC with ventral striatum, regardless of sex, whereas reduced FA in the OFC-amygdala and ventral ACC-amygdala tracts were specific to boys with ADHD. Across diagnostic groups and sex, reduced FA in the dorsal ACC-executive striatum tract correlated with greater game time delay discounting. CONCLUSIONS: These results suggest a potential neurobiological substrate of heightened delay discounting in children with ADHD and support the need for additional studies including larger sample sizes of girls with ADHD to further elucidate ADHD-related sex differences in these relationships.

Reliability and validity of behavioral-economic measures: A review and synthesis of discounting and demand.

This review sought to synthesize the literature on the reliability and validity of behavioral-economic measures of demand and discounting in human research, introduce behavioral-economic research methodologies for studying addictive behaviors, discuss gaps in the current literature, and review areas for future research. A total of 34 studies was included in this review. The discounting literature showed similar responding regardless of whether hypothetical or actual outcomes were used, though people tended to discount the outcome presented first more steeply, suggesting order effects. Although delay-discounting measures seem to show temporal stability, exceptions were found for probability- and experiential-discounting tasks. The demand literature also demonstrated similar responding regardless of outcome type; however, some demand indices showed exceptions. Randomized price sequences tended to show modest increases in Omax and α and modestly higher rates of inconsistent or nonsystematic responses compared with sequential price sequences. Demand indices generally showed temporal stability, although the stability was weaker the larger the time interval between test sessions. Future studies would benefit by examining addictive commodities beyond alcohol, nicotine, and money; examining temporal stability over longer time intervals; using larger delays in discounting tasks; and using larger sample sizes.

Neural correlates of decreased impulsivity during delay discounting task after laparoscopic sleeve gastrectomy.

OBJECTIVE: The goal of this study was to investigate laparoscopic sleeve gastrectomy (LSG)-induced changes in choice impulsivity and the neural correlates in individuals with obesity (OB). METHODS: The study employed functional magnetic resonance imaging with a delay discounting task in 29 OB tested before and 1 month after LSG. Thirty participants with normal weight matched to OB with gender and age were recruited as the control group and underwent an identical functional magnetic resonance imaging scan. Alterations in activation and functional connectivity between pre- and post-LSG were investigated and compared with participants with normal weight. RESULTS: OB exhibited significantly reduced discounting rate after LSG. During the delay discounting task, hyperactivation in dorsolateral prefrontal cortex, right caudate, and dorsomedial prefrontal cortex decreased in OB after LSG. LSG additionally engaged compensatory effects through increased activation in bilateral posterior insula and functional connectivity between caudate and dorsomedial prefrontal cortex. Those changes were associated with decreased discounting rate and BMI as well as improved eating behaviors. CONCLUSIONS: These findings indicate that decreased choice impulsivity following LSG was associated with the changes in regions involved in executive control, reward evaluation, interoception, and prospection. This study may provide neurophysiological support for the development of nonoperative treatments such as brain stimulation for individuals with obesity and overweight.

"Ten euros now" temporal discounting in Huntington disease.

BACKGROUND: When making decisions, one often faces a trade-off between immediate and long-term rewards. In these situations, people may prefer immediate over later rewards, even if immediate rewards are smaller than later ones; a phenomenon known as temporal discounting. In this study, we, for the first time, assessed temporal discounting in three populations: participants with manifest Huntington disease (HD), participants with premanifest HD, and control participants. METHODS: Using the temporal discounting task, we invited participants to choose between small immediate amount of money vs. delayed, but larger amount of money (e.g., "Which do you prefer: you get 10 euros right now or 50 euros in a month?"). We also measured inhibition in order to test if it impacts discounting performance. RESULTS: Analysis demonstrated higher temporal discounting (i.e., a preference for the immediate rewards) in participants with manifest HD compared to those with premanifest HD or control participants, but no significant differences were observed in participants with premanifest HD and control participants. Analysis also demonstrated significant correlations between temporal discounting and scores on an inhibition test in participants with manifest HD, but not in those with premanifest HD or in control participants. DISCUSSION: We suggest that, when making decisions, patients with manifest HD may have difficulties with suppressing the temptation of smaller, but immediate, rewards.

"Ten dollars today or 50 dollars after one month?" Temporal discounting in Korsakoff syndrome.

OBJECTIVE: Little research has investigated decision making in patients with Korsakoff syndrome (KS). Specifically, to our knowledge, there is a lack of research investigating whether patients with KS may tend to prefer immediate over future rewards (i.e., temporal discounting). Further, we investigated the relationship between temporal discounting and inhibition. METHODS: We, for the first time, invited patients with KS and control participants to perform a temporal discounting task, in which they answered questions probing preferences between an immediate, but smaller amount of money, and a delayed, but larger amount of money (e.g., "would you prefer 10 dollars today or 50 dollars after one month?"). Furthermore, inhibition was measured using the Stroop Colour Word Test. RESULTS: Analysis demonstrated higher temporal discounting in patients with KS than in control participants. Temporal discounting in both populations was significantly correlated with inhibition. CONCLUSIONS: Patients with KS may have difficulties to suppress the temptation of smaller, but immediate, rewards.

Optogenetic disruption of the prelimbic cortex alters long-term decision strategy but not valuation on a spatial delay discounting task.

Rats demonstrate a preference for smaller, immediate rewards over larger, delayed ones, a phenomenon known as delay-discounting (DD). Behavior arises from the interaction of multiple decision-making systems, and the medial prefrontal cortex (mPFC) has been identified as a central component in the mediation between these decision systems. To investigate the role of the prelimbic (PL) subregion of mPFC on decision strategy interaction, we compared two cohorts of rats (ChR2-opsin-expressing 'Active' and opsin-absent 'Control') on a spatial delay-discounting task while delivering in-vivo light stimulation into PL at the choice point of select trials. By analyzing the overall delay-adjustment along with deliberative and procedural behavioral strategy markers, our study revealed differences in the decision strategies used between the active and control animals despite both groups showing similar valuations. Control animals developed the expected shift from deliberative to procedural decision strategy on this task (indicated by reaching delay-stability, particularly during late-session laps); however, active-virus animals repeatedly over-adjusted around their preferred delay throughout the entire session, suggesting a significant deficit in procedural decision-making on this task. Active animals showed a significant decrease in proportion of vicarious trial and error events (VTE, a behavior correlated with deliberative processes) on delay adjustment laps relative to control animals. This points to a more nuanced role for VTE, not just in executing deliberation, but in shifting from deliberative to procedural processes. This opto-induced change in VTE was especially pronounced for late-session adjustment laps. We found no other session-by-session or lap-by-lap effects, leaving a particular role for PL in the long-term development of procedural strategies on this task.

An fMRI-Based Brain Marker of Individual Differences in Delay Discounting.

Individual differences in delay discounting-how much we discount future compared to immediate rewards-are associated with general life outcomes, psychopathology, and obesity. Here, we use machine learning on fMRI activity during an intertemporal choice task to develop a functional brain marker of these individual differences in human adults. Training and cross-validating the marker in one dataset (Study 1, N = 110 male adults) resulted in a significant prediction-outcome correlation (r = 0.49), generalized to predict individual differences in a completely independent dataset (Study 2: N = 145 male and female adults, r = 0.45), and predicted discounting several weeks later. Out-of-sample responses of the functional brain marker, but not discounting behavior itself, differed significantly between overweight and lean individuals in both studies, and predicted fasting-state blood levels of insulin, c-peptide, and leptin in Study 1. Significant predictive weights of the marker were found in cingulate, insula, and frontoparietal areas, among others, suggesting an interplay among regions associated with valuation, conflict processing, and cognitive control. This new functional brain marker is a step toward a generalizable brain model of individual differences in delay discounting. Future studies can evaluate it as a potential transdiagnostic marker of altered decision-making in different clinical and developmental populations.SIGNIFICANCE STATEMENT People differ substantially in how much they prefer smaller sooner rewards or larger later rewards such as spending money now versus saving it for retirement. These individual differences are generally stable over time and have been related to differences in mental and bodily health. What is their neurobiological basis? We applied machine learning to brain-imaging data to identify a novel brain activity pattern that accurately predicts how much people prefer sooner versus later rewards, and which can be used as a new brain-based measure of intertemporal decision-making in future studies. The resulting functional brain marker also predicts overweight and metabolism-related blood markers, providing new insight into the possible links between metabolism and the cognitive and brain processes involved in intertemporal decision-making.

The relationship between nonsystematic delay discounting and low-quality survey responses in a sample of smokers: ROC curve analysis.

Delay discounting (DD), the decrease of the subjective value of a reward as the delay to its receipt increases, is a crucial aspect of decision-making processes. As evidence continues to mount, additional attention needs to be given to nonsystematic DD, a response pattern that has been reported in the literature but rarely investigated. We noticed in our recent online research an increase in the proportion of nonsystematic DD responses across samples, consistent with the so-called Amazon Mechanical Turk (MTurk) data quality crisis. The significant proportion of nonsystematic responses created an opportunity to investigate its association with data quality in the present study. In a sample of smokers recruited from MTurk (n = 210), three independent quality check indexes evaluated participants' response quality. The degree of nonsystematic DD was quantified by the algorithms developed by Johnson and Bickel (2008). The area under the receiver operating characteristic curve (AUC) predicting response quality by nonsystematic DD was obtained. The observed AUC values were at the extreme of the null distributions (ps < .001) in a permutation test. Furthermore, the nonsystematic DD cutoffs provided in Johnson and Bickel (2008) showed good sensitivity (0.77-0.93), albeit low-moderate specificity (0.42-0.74), in detecting low-quality responses. The findings showed that nonsystematic DD was associated with low-quality responses, although other factors contributing to the nonsystematic responses remain to be identified. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Sequential delay and probability discounting tasks in mice reveal anchoring effects partially attributable to decision noise.

Delay discounting and probability discounting decision making tasks in rodent models have high translational potential. However, it is unclear whether the discounted value of the large reward option is the main contributor to variability in animals' choices in either task, which may limit translation to humans. Male and female mice underwent sessions of delay and probability discounting in sequence to assess how choice behavior adapts over experience with each task. To control for "anchoring" (persistent choices based on the initial delay or probability), mice experienced "Worsening" schedules where the large reward was offered under initially favorable conditions that became less favorable during testing, followed by "Improving" schedules where the large reward was offered under initially unfavorable conditions that improved over a session. During delay discounting, both male and female mice showed elimination of anchoring effects over training. In probability discounting, both sexes of mice continued to show some anchoring even after months of training. One possibility is that "noisy", exploratory choices could contribute to these persistent anchoring effects, rather than constant fluctuations in value discounting. We fit choice behavior in individual animals using models that included both a value-based discounting parameter and a decision noise parameter that captured variability in choices deviating from value maximization. Changes in anchoring behavior over time were tracked by changes in both the value and decision noise parameters in delay discounting, but by the decision noise parameter in probability discounting. Exploratory decision making was also reflected in choice response times that tracked the degree of conflict caused by both uncertainty and temporal cost, but was not linked with differences in locomotor activity reflecting chamber exploration. Thus, variable discounting behavior in mice can result from changes in exploration of the decision options rather than changes in reward valuation.

Delay discounting and alcohol consumption correlate with dorsal anterior insula activation during choice in nontreatment-seeking heavy drinkers.

BACKGROUND: The anterior insular cortex (AIC), a prominent salience network node, integrates interoceptive information and emotional states into decision making. While AIC activation during delay discounting (DD) in alcohol use disorder (AUD) has been previously reported, the associations between AIC activation, impulsive choice, alcohol consumption, and connectivity remain unknown. We therefore tested AIC brain responses during DD in heavy drinkers and their association with DD performance, alcohol drinking, and task-based connectivity. METHODS: Twenty-nine heavy drinkers (12 females; mean (SD) age=31.5 ± 6.1 years; mean (SD)=40.8 ± 23.4 drinks/week) completed a DD task during functional MRI. Regions activated during DD decision making were tested for correlation with DD behavior and alcohol drinking. Psychophysiological interaction (PPI) models assessed the task-dependent functional connectivity (FC) of activation during choice. RESULTS: Delay discounting choice activated bilateral anterior insular cortex, anterior cingulate cortex, and left precentral gyrus. Right dorsal (d) AIC activation during choice negatively correlated withdiscounting of delayed rewards and alcohol consumption. PPI analysis revealed FC of the right dAIC to both the anterior and posterior cingulate cortices-key nodes in the midline default mode network. CONCLUSIONS: Greater dAIC involvement in intertemporal choice may confer more adaptive behavior (lower impulsivity and alcohol consumption). Moreover, salience network processes governing discounting may require midline default mode (precuneus/posterior cingulate cortex) recruitment. These findings supporta key adaptive role for right dAIC in decision making involving future rewards and risky drinking.

Delay of gratification dissociates cognitive control and valuation brain regions in healthy young adults.

Delay of gratification (DofG) refers to an inter-temporal choice phenomenon that is of great interest in many domains, including animal learning, cognitive development, economic decision-making, and executive control. Yet experimental tools for investigating DofG in human adults are almost non-existent, and as a consequence, very little is known regarding the brain basis of core DofG behaviors. Here, we utilize a novel DofG paradigm, adapted for use in neuroimaging contexts, to examine event-related changes in neural activity as healthy young adult participants made repeated choices to continue waiting for a delayed reward, rather than take an immediately available one of lesser value. On DofG trials, choose-to-wait events were associated with increased activation in fronto-parietal and cingulo-opercular regions associated with cognitive control. Activity in the right lateral prefrontal cortex (PFC) was also associated with individual variability in task performance and strategy. Fronto-parietal activity was clearly dissociable from that observed in ventromedial PFC, as this latter region exhibited a ramping-up pattern of activity during the waiting period prior to reward delivery. Ventromedial PFC ramping activity dynamics were further selective to DofG trials associated with increased future reward rate, consistent with the involvement of this region in subjective reward valuation that incorporates higher-order task structure. These results provide important initial validation of this experimental paradigm as a useful tool for investigating and isolating unique DofG neural mechanisms, which can now be utilized to study a wide-variety of populations and task factors.

More than meets the eye: Examining physiological and behavioral regulation during delay of gratification task.

Children continually encounter situations where they must regulate impulsive responses to achieve a goal, requiring both self-control (SC) and delay of gratification. We examined concurrent behavioral SC strategies (fidgeting, vocalizations, anticipation) and physiological regulation (heart rate [HR], respiratory sinus arrhythmia [RSA]) in 126 children (M (SD) = 5.4 (0.29) years) during a standard delay of gratification task. Latent variable models derived latent SC classes and examined the moderating role of HR/RSA on SC and delay ability. Three classes of SC were identified: passive: low fidgeting and vocalizations, moderate anticipation; active: moderate fidgeting, low vocalizations, and high anticipation; and disruptive: moderate fidgeting, high vocalizations, and high anticipation. Children in the active class had the lowest odds of delaying full task time, compared to children in the passive (OR = 0.67, z = -5.25, p < .001) and disruptive classes (OR = 0.76, z = -2.03, p = .04). RSA changes during the task moderated the relationship between SC class and delay ability for children in the active class (aOR = 0.92, z = -3.1, p < .01). Within the group who struggled to delay gratification (active class), a subset exhibiting appropriate autonomic regulation was able to delay. The findings suggest probing congruency of observed behavioral and unobserved physiological regulation.

Testing delay of gratification in rats using a within-session increasing-delay task.

In delay discounting, preference reversals refer to shifts in preference from a larger-later reward to a smaller-sooner reward. Steep hyperbolic discounting predicts a preference reversal when a smaller-sooner and larger-later reward both become temporally proximal; prior research is consistent with this prediction. Hyperbolic discounting does not predict a preference reversal, however, after an individual chooses a larger-later reward over a smaller-immediate reward; prior research is inconsistent with this prediction. We sought to replicate and extend these findings using a delay of gratification task in rats. The task included a defection response which allowed rats to reverse their preference after choosing a larger-later sucrose reinforcer to instead obtain a smaller-immediate sucrose reinforcer. In Experiment 1, we found that rats would defect on their choice of the larger-later reinforcer, systematically replicating prior research. We also found that experience on the delay of gratification task led to decreases in defection responses. In Experiment 2, we found that prior experience on an intertemporal choice task, with no opportunity to defect, also led to few defection responses on the delay of gratification task. We discuss our findings in the context of whether inhibitory control or temporal learning could be involved in delay of gratification.