Delay Discounting Task Research Articles

Exposure to Nicotine Vapor Produced by an Electronic Nicotine Delivery System Causes Short-Term Increases in Impulsive Choice in Adult Male Rats.

Traditional cigarette use influences cost-benefit decision making by promoting impulsive choice. However, the impact of nicotine exposure via electronic nicotine delivery systems on impulsivity remains unclear. Hence, the present study examined the short- and long-term effects of nicotine vapor on impulsive choice. Twenty-four adult male rats were trained in the delay discounting task to choose between small immediate food rewards and large delayed food rewards. After 24 days of training in the task rats were exposed to vapor containing either 0, 12, or 24 mg/mL of nicotine for 10 days. To validate inhalation of nicotine vapor serum cotinine levels were analyzed on exposure days 1, 5, and 10 using enzyme-linked immunosorbent assay. Following vapor exposure, rats were retrained in the discounting task until rats displayed stable responding and the effects of nicotine vapor on choice preference were assessed. Rats exposed to 12 and 24 mg/mL nicotine vapor displayed higher serum cotinine levels than control rats exposed to 0 mg/mL vapor. There were no differences in impulsive choice between any vapor exposure groups when tested 15 days after exposure, across 6 days of stable responding, suggesting that nicotine vapor does not have long lasting effects on impulsive choice. Interestingly, a subsequent nicotine vapor challenge revealed short-term increases in impulsive choice immediately following a single exposure to 24 mg/mL nicotine vapor, relative to choice preference immediately following exposure to 0 mg/mL vapor. These results suggest that exposure to nicotine vapor causes immediate, short-term increases in impulsive choice. E-cigarette use is increasing at an alarming rate, particularly among adolescents and young adults. This is concerning given the lack of research into the effects of nicotine vapor exposure on the brain and behavior. The present study describes a viable rodent model of human e-cigarette use and suggests that exposure to nicotine vapor produces short-term increases in impulsive choice.

Altered effective connectivity of the reward network during an incentive-processing task in adults with alcohol use disorder.

Abnormalities of reward sensitivity and impulsivity are known to be correlated with each other and alcohol use disorder (AUD) risk, but the underlying aberrant neural circuitry involved is not clearly defined. We sought to extend the current knowledge of AUD pathophysiology by studying incentive processing in persons with AUD using functional neuroimaging data. We utilized functional MRI data from the Human Connectome Project Database obtained during performance of a number-guessing incentive-processing task with win, loss, and neutral feedback conditions in 78 participants with either DSM-IV alcohol abuse or dependence (combined as the AUD group) and 78 age- and sex-matched control (CON) participants. Within a network consisting of anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), insula, ventral striatum, and dorsal striatum (DS) in the right hemisphere, we performed dynamic causal modeling analysis to test group-level differences (AUD vs. CON) in effective directional connectivity (EC) as modulated by "win" and "loss" conditions. We used linear regression analyses to characterize the relations between each EC outcome and measures of cumulative alcohol exposure and impulsivity. During wins, AUD participants had lower ECs from ACC to the other four nodes, greater ECs from insula to the other four nodes, greater ECs from DLPFC to the other four nodes, and greater DS to DS self-connection EC than CON participants. In the total sample, EC from the insula to the DLPFC (insula→DLPFC) during wins was positively correlated with both impulsivity (as measured by the delay-discounting task) and cumulative alcohol exposure. The DS to DS self-connection EC during wins was positively correlated with impulsivity. Many of the altered ECs from the ACC and insula to other nodes were correlated with cumulative alcohol exposure. Individuals with AUD have disrupted EC in both instrumentally driven and automatized corticostriatal reward circuits during non-alcohol reward feedback. These results point to disrupted corticostriatal EC in both "top-down" and "bottom-up" pathways among individuals with AUD.

Decision Making and Impulsivity in Young Adult Cannabis Users.

Aims: Chronic cannabis users show impairments on laboratory measures of decision making which reflect risk factors for initiation and continued use of cannabis. However, the differential sensitivity of these tasks to cannabis use has not been established. Moreover, studies to date have often lacked assessment of psychiatric histories and use of other illicit substances, both of which may influence decision making outcomes. The current study aimed to address these limitations by (1) including multiple types of decision making tasks, (2) implementing the Probabilistic Reversal Learning Task, a measure of decision making under uncertainty, for the first time in cannabis users, (3) including young adult cannabis users with no other psychiatric disorders, and (4) conducting urinalysis to exclude users of other illicit drugs.Methods: Thirty-three current cannabis users without comorbid psychiatric disorders and 35 cannabis non-users completed behavioral measures of decision-making (Iowa Gambling Task), reward discounting (Delay Discounting Task), choice-outcome learning (the Probabilistic Reversal Learning Task) and a questionnaire assessment of impulsivity (Barratt Impulsiveness Scale).Results: Relative to non-users, cannabis users demonstrated greater preference for immediate vs. delayed rewards on the Delay Discounting Task, made fewer advantageous decisions on the Iowa Gambling Task, and endorsed greater impulsivity on the Barratt Impulsiveness Scale scales. Cannabis users and non-users showed comparable performance on the Probabilistic Reversal Learning Task. Frequency of past-month cannabis use and total years of use did not predict decision making or impulsivity.Conclusions: Young adult cannabis users demonstrated higher discounting rates and impairments in learning cost-benefit contingencies, while reversal learning was unaffected. Self-reported impulsivity was elevated as well. None of these measures correlated with current or lifetime estimates of cannabis use, arguing against a dose-relationship. Interventions that target improvement in affected components of decision making may be helpful in reducing cannabis use and relapse.

Development of a cortical delay discounting assay: a potential biomarker of externalizing disorders.

People who tend to impulsively choose smaller, sooner rewards over larger, later rewards are at increased risk for addiction and psychiatric disorders. A neurobiological measure of the tendency to overvalue immediate gratification could facilitate the study of individuals who are susceptible to these mental disorders. The objective of this research was to develop a cortical assay of impulsive choice for immediate rewards. A cortex-based assay of impulsive choice was developed using 1105 healthy adults from the Human Connectome Project, and then cross-validated in two independent samples of adults with elevated rates of psychiatric disorders. Study 1: Cortical delay discounting (C-DD) was developed using a multivariate additive model of gray matter thickness across both hemispheres. Higher C-DD corresponded to thinner cortex and greater impulsive choice for immediate rewards. It also predicted cannabis use beyond established risk factors for drug use, including familial substance use, childhood conduct problems, personality traits, and cognitive functioning. Study 2: C-DD replicated the association with delay discounting performance from study 1. Structural equation modeling showed C-DD covaried with symptoms of externalizing, but not internalizing disorders. Study 3: C-DD positively predicted future delay discounting behavior (6-34 months later). Across three studies, a cortical assay of impulsive choice evidenced consistent associations with drug use and delay discounting task performance. It was also uniquely associated with psychiatric disorders that share impulsivity as a core feature. Together, findings support the utility of C-DD as a neurobiological assay of impulsive decision-making and a possible biomarker of externalizing disorders.

Effects of Psychopathy on Neurocognitive Domains of Impulsivity in Abstinent Opiate and Stimulant Users.

Background: Psychopathy and substance use disorders (SUDs) are both characterized by neurocognitive impairments reflecting higher levels of impulsivity such as reward-driven decision-making and deficient inhibitory control. Previous studies suggest that psychopathy may exacerbate decision-making deficits, but it may be unrelated to other neurocognitive impairments among substance dependent individuals (SDIs). The aim of the present study was to examine the role of psychopathy and its interpersonal-affective and impulsive-antisocial dimensions in moderating the relationships between dependence on different classes of drugs and neurocognitive domains of impulsivity.Method: We tested 693 participants (112 heroin mono-dependent individuals, 71 heroin polysubstance dependent individuals, 115 amphetamine mono-dependent individuals, 76 amphetamine polysubstance dependent individuals, and 319 non-substance dependent control individuals). Participants were administered the Psychopathy Checklist: Screening Version (PCL:SV) and seven neurocognitive tasks measuring impulsive choice/decision-making (Iowa Gambling Task; Cambridge Gambling Task; Kirby Delay Discounting Task; Balloon Analog Risk Task), and impulsive action/response inhibition (Go/No-Go Task, Immediate Memory Task, and Stop Signal Task).Results: A series of hierarchical multiple regressions revealed that the interpersonal-affective dimension of psychopathy moderated the association between decision-making, response inhibition and both amphetamine and heroin dependence, albeit differently. For amphetamine users, low levels of interpersonal-affective traits predicted poor decision-making on the Iowa Gambling Task and better response inhibition on the Stop Signal task. In contrast, in heroin users high interpersonal-affective psychopathy traits predicted lower risk taking on the Cambridge Gambling Task and better response inhibition on the Go/No-Go task. The impulsive-antisocial dimension of psychopathy predicted poor response inhibition in both amphetamine and heroin users.Conclusions: Our findings reveal that psychopathy and its dimensions had both common and unique effects on neurocognitive function in heroin and amphetamine dependent individuals. Our results suggest that the specific interactions between psychopathy dimensions and dependence on different classes of drugs may lead to either deficient or superior decision-making and response inhibition performance in SDIs, suggesting that psychopathy may paradoxically play a protective role for some neurocognitive functions in specific subtypes of substance users.

The effects of COVID-19 on test-retest reliability in a behavioral measure for impulsivity

ABSTRACT Predictive power of many behavioral measures relies on high test-retest reliability, whereby a measure yields similar data when repeated measure administration occurs at spaced-out intervals. However, major environmental disruptions between measure administration may impact test-retest reliability. The novel coronavirus (COVID-19) pandemic caused just such a major environmental disruption. We collected impulsivity data via a delay discounting task before, during, and after this environmental disruption. Test-retest reliability was generally statistically significant throughout the study even as delay discounting rates changed in the expected direction between the two experimental groups. Importantly, non-significant correlation coefficients (i.e. poor test-retest reliability) typically occurred immediately after the environmental disruption. Participant’s anecdotal self-reports corroborated COVID-19’s temporary disruptive impact. Although not a planned manipulation, this data provides useful information about whether major environmental disruptions may impact test-retest reliability for events that may not be replicable during a controlled experiment. Social and behavioral scientists attempting behavioral measurement through well-validated measures should be aware of whether large environmental changes can affect measure reliability, and how long such a disruption may last.

A story to tell: the role of narratives in reducing delay discounting for people who strongly discount the future

ABSTRACT Delay Discounting (DD) or devaluing a future, larger reward in favour of a smaller, more immediate reward, has been linked to negative health behaviours. One intervention that reduces DD is Episodic Future Thinking (EFT). EFT has participants generate cues representing positive future events that correspond to temporal windows during the DD task. The current study examined if incorporating EFT cues into narratives would strengthen effects on DD. One hundred and sixty adults were recruited from Amazon Mechanical Turk and were randomised to traditional or narrative EFT. Results showed that participants in narrative EFT discounted the future less (p = 0.034) than participants who engaged in traditional EFT. This novel approach to EFT is well grounded in research and theory on the power of narratives to influence behaviour and can open a new window into ways to reduce DD to strengthen engagement in positive choices.

Appetite-Regulating Hormone Ghrelin Predicts Decision-Making in Healthy Controls but Not Individuals With Low-Weight Eating Disorders

Background: Ghrelin is an orexigenic hormone known to regulate appetite, glucose homeostasis, and other food-related functions. The potential role of ghrelin beyond energy homeostasis is not well understood. Ghrelin receptors are evident in the mesolimbic reward pathway, and preclinical research has shown that ghrelin administration increases impulsive behavior and choices in rats. However, little is known about whether and how ghrelin is associated with food-independent behavior and decision-making in humans. We investigated the relationship between ghrelin levels and monetary decision-making using a well-established behavioral paradigm in healthy individuals and individuals with a low-weight eating disorder (LWED), as patients with LWEDs have been shown to have high ghrelin levels and resistance to the effects of this hormone. We hypothesized that higher ghrelin levels would predict more impulsive choices of immediate rewards in healthy individuals, while this relationship would be less pronounced in individuals with LWEDs. Methods: Sixty-four female participants with a LWED and 34 healthy controls (HC), aged 10-22 years, presented after a 10-hour fast to undergo a standardized mixed meal followed by a delay discounting task. During this task, participants decided between smaller immediate and larger delayed monetary rewards. Based on their choices, the delay discounting parameter k was calculated as a marker of choice preferences with higher values indicating a stronger preference for the immediate smaller reward. Blood was drawn prior to and 30, 60, and 120 min after the meal for analysis of ghrelin, and area under the curve was calculated as a cumulative measurement of ghrelin levels. Results: As per study design, BMI was lower in the LWED group (17.3±1.5 kg/m2) compared to the HC group (mean±SD: 21.4±2.5 kg/m2; t[96]=11.33, p<0.0001, d=-1.99). Groups did not differ by age (LWED: 18.3±3.2 years, HC: 18.0±3.1 years; t[96]=-0.36, p=0.720, d=-0.10). Ghrelin levels were higher in the LWED compared to HC group (t[96]=-2.67, p=0.009, d=0.57). K was numerically lower in the LWED compared to the HC group, but the difference was not significant (t[96]=1.37, p=0.175, d=-0.30). Importantly, in HC higher ghrelin levels were associated with higher k values (r=0.37, p=0.032). This relationship was not observed in the LWED group (r=-0.13, p=0.304). Conclusions: In HC, higher levels of ghrelin predicted a stronger preference for smaller immediate rewards, which is consistent with increased impulsive choices shown in animal research. We did not observe this relationship in our LWED sample. Our results indicate that beyond energy homeostasis, ghrelin might play a broader role in reward-related behavior and decision-making, such as monetary choices. Future studies are required to further explore the role of ghrelin in human behavior in both clinical and non-clinical populations.

085 Effort Exertion and Good Sleep Interactively Increase the Subjective Value of the Future

Abstract Introduction The present study examined how habitual variation in sleep quality shapes reward responsivity following effort exertion. Behavioural and neuroscientific theory and research suggest that expending effort leads to compensatory increases in reward responsivity. Converging evidence links the preference for larger-but-delayed rewards to increases in reward sensitivity in psychophysiological, psychopharmacological, and animal studies. Accordingly, we hypothesized that exerting mental effort would increase the preference for larger-but-delayed rewards (i.e., the subjective value of the future) insofar as these preferences reflect elevated reward responsivity. Furthermore, given that sleep shapes perceptions of effort and preferences for larger-but-delayed rewards, we hypothesized that this finding would be moderated by habitual variation in sleep quality, with the strongest effects apparent among participants reporting habitually good sleep. Methods To test these hypotheses, we recruited 79 participants to complete a 10-minute effortful (vs. control) writing task followed by a delay discounting task and the Pittsburgh Sleep Quality Index. Results As hypothesized, the effortful writing task (vs. control) participants demonstrated a greater preference for larger-but-delayed rewards (vs. smaller-but-immediate rewards). This effect was moderated by sleep quality with those high but not low in sleep quality showing the hypothesized effect. Conclusion Ultimately, we found that exerting mental effort increases the subjective value of the future, particularly among participants who habitually report good sleep. These results suggest that good sleep quality helps us contend with the effortful demands of daily life in a way that promotes long-term goal pursuit. Support (if any):

Sex differences in economic decision-making: Exogenous estradiol has opposing effects on fairness framing in women and men

Burgeoning evidence indicates that women are more sensitive to the context of an offer and show a stronger propensity to adjust their behavior with changing fairness frames. We evaluated whether the sex hormone estradiol and associated stereotypical beliefs contribute to fairness framings by administering topical estradiol (2 mg) to 108 healthy women and 104 heathy men in a randomized, double-blind, placebo-controlled between-subject study design. Participants played the role of the responder in a modified version of the Ultimatum Game (UG), in which identical offers for the division of a given amount of money were framed as either fair or unfair. Furthermore, participants completed an unframed UG and a delayed discounting task to probe possible effects of estradiol on altruistic preferences and delay gratification. Our results show that women were more sensitive to fairness frames than men. Intriguingly, however, estradiol had sex-specific effects on fairness sensitivity by increasing the acceptance rate of proposals with a fair frame in men and reducing it in women. Furthermore, the mere belief of receiving estradiol treatment significantly increased the acceptance of unfair-framed offers in both sexes, but estradiol did not significantly alter the response to unframed offers and impulsive decision-making. Collectively, our findings indicate that estradiol has opposing effects on the sensitivity to the perceived fairness of economic offers in women and men. The profound effects of estradiol treatment and stereotypical beliefs provide support for the notion that sex differences in fairness framing are rooted in both biological and environmental factors.

Personality and media multitasking in the college classroom: Context-dependent implications of conscientiousness and agreeableness

Both personality and contexts may account for media multitasking in the college classroom. As this area of research was lacking, the present study examined which personality traits would be associated with in-class media multitasking in different contexts of text messaging. Undergraduate students (83 males and 65 females; average age: 20.0 [SD = 4.3]) completed a questionnaire on demographic characteristics, general text-messaging behavior, and Big Five personality traits as well as a delay-discounting task. This task had two hypothetical scenarios in which participants received either an urgent text message from their significant other (Significant Other condition) or a non-urgent message from a casual friend (Casual Friend condition), and they rated their likelihood of immediately replying to the message during the class versus waiting to reply until the class was over. For each of the conditions, hierarchical regression analyses were conducted to examine whether personality traits predicted the likelihood of waiting, after controlling for demographic characteristics and general text-messaging behavior. Whereas only conscientiousness independently predicted the likelihood of waiting in the Significant Other condition (β = .20, p = .033), only agreeableness independently predicted the likelihood in the Casual Friend condition (β = .27, p = .002). These findings contribute to the sparse literature on links of personality traits and in-class media multitasking by highlighting the possible context-dependent aspects of these links. The findings also indicate potential directions of future research including exploring approaches to reducing media multitasking in the college classroom while taking both personality and specific contexts into consideration.

Written or drawn episodic future thinking cues improves delay discounting in adults

Delay discounting (DD) describes choices between small, immediate rewards and larger, delayed rewards. Individuals who are high in DD favor small, immediate rewards, and this preference is related to health behaviors including higher energy intake, smoking and less physical activity. Episodic future thinking (EFT) is an intervention in which one thinks about personal positive future events and this decreases DD in adults and children. In previous studies episodic events have been presented as written or auditory cues. Episodic future images are also imagined visually, but the impact of personal visual cues has not been tested. Research examining sensory modality and semantic memory has shown drawn items are associated with better recall than writing or viewing provided images. This study compared drawn versus written episodic future or recent cues on DD. Sixty-nine adults were randomized to one of three groups; EFT-written, EFT-drawn or Episodic recent thinking (ERT)-written cues, and completed a computerized adjusting amount DD task cued with episodic events. Results showed both written and drawn EFT cues had a larger effect on DD than ERT-written cues and individual differences in immediate time perspective moderated this effect. This suggests that drawn and written cues can have similar effects on DD, providing future clinical work flexibility in how to present cues in the field. In addition, presenting drawn cues may improve DD for individuals who have an immediate time perspective.

Executive Functions in Tobacco Use Disorder: New Challenges and Opportunities.

There is increasing evidence that executive functions have significative effects on nicotine abuse. An unresolved challenge for smoking cessation interventions is the detection of factors associated with nicotine use. In order to understand how cognition is affected by nicotine abuse, this study was designed to determine the relationship between years of smoking addiction and several variables of executive functions. The sample was composed of 174 smokers, whose age ranged between 27 and 69 years old (M = 47.44; SD = 8.48). Smokers were assessed at baseline with measures of cognitive inhibition [Go/No Go Task and Five Digit Test (FDT)], updating [Visual Search and Attention Test (VSAT) and Letter-Number Sequencing (WAIS IV)] and shifting [Delay Discounting Task (DDT) and Iowa Gambling Task (IGT)] while the outcome measure was years of smoking. The linear regression and correlation analysis highlighting that the variable which has the strongest association with years of smoking is updating. Multivariate analysis of variance (MANCOVA) followed by Tukey post-hoc tests revealed significant differences such that heavy smoking indicated worse performance than light smoking on updating tasks. These findings report the ability of working memory to predict years of smoking and suggest that cigarette packaging warning may experience a loss of effectiveness in heavy smokers.

Impact of neuropsychological disorders on clinical aspects of smoking.

Studies examining associations between cognitive measures and clinical aspects of smoking are scarce and generally limited to predicting risk profiles or relapses. However, it is essential to understand the influence of several measures of executive function in nicotine addiction in order to investigate factors associated with smoking maintenance. This study examined the ability of working memory and delay discount to predict years of smoking. The sample consisted of 180 smokers who were assessed at baseline with measures of cognitive impulsivity (Delay Discounting Task) and working memory [Visual Search and Attention Test (VSAT) and Letter-Number Sequencing (WAIS III)] while the outcome measure was years of smoking. Consistent with predictions, working memory evaluated with Visual Search and Attention Test was a statistically significant factor in predicting years of nicotine addiction. These findings suggest that working memory is clinically relevant in nicotine dependence and proposes a pattern of executive functioning associated with smoking.

Delay discounting and neurocognitive correlates among inner city adolescents with and without family history of substance use disorder

Adolescents with a family history (FH+) of substance use disorder (SUD) are at a greater risk for SUD, suggested to be partly due to the transmission of behavioral impulsivity. We used a delay discounting task to compare impulsivity in decision-making and its associated brain functioning among FH+ and FH - minority adolescents. Participants chose between Smaller Sooner (SS) and Larger Later (LL) rewards. The SS was available immediately (Now trials) or in the future (Not-Now trials), allowing for greater differentiation between impulsive decisions. The FH+ group showed greater impatience by responding SS more frequently than the FH - group, only on the Now trials, and even when the relative reward differences (RRD) increased. Surprisingly, there were no differences in brain activity between the groups. Combined, the groups showed greater reward activity during the Now vs. Not-Now trials in medial prefrontal/anterior cingulate, posterior cingulate, precuneus, and inferior frontal gyrus (i.e., an immediacy effect). As the RRD increased activation in the reward network decreased, including the striatum, possibly reflecting easy decision-making. These results indicate that risk for SUD, seen behaviorally among FH+ adolescents, may not yet be associated with discernable brain changes, suggesting that early intervention has the potential to reduce this risk.

Role of temporal discounting in a conditional cash transfer (CCT) intervention to improve engagement in the prevention of mother-to-child transmission (PMTCT) cascade

BackgroundTemporal discounting, the tendency of individuals to discount future costs and benefits relative to the present, is often associated with greater engagement in risky behaviors. Incentives such as conditional cash transfers (CCTs) have the potential to counter the effects of high discount rates on health behaviors.MethodsWith data from a randomized trial of a CCT intervention among 434 HIV-positive pregnant women in the Democratic Republic of Congo, we used binomial models to assess interactions between discount rates (measured using a delay-discounting task) and the intervention. The analysis focused on two outcomes: 1) retention in HIV care, and 2) uptake of prevention of mother-to-child transmission (PMTCT) services.ResultsThe effect of high discount rates on retention was small, and we did not observe evidence of interaction between high discount rates and CCT on retention. However, our findings suggest that CCT may mitigate the negative effect of high discount rates on uptake of PMTCT services (interaction contrast (IC): 0.18, 95% CI: − 0.09, 0.44).ConclusionsOur findings provide evidence to support the continued use of small, frequent incentives, to motivate improved uptake of PMTCT services, especially among women exhibiting high rates of temporal discounting.Trial registrationClinicaltrials.gov number NCT01838005, April 23, 2013.

More Later: Delay of Gratification and Thought About the Future in Children.

We investigated whether individual differences in future time perception and the detail with which future events are imagined are related to children's delay of gratification. We administered a delay choice task (real rewards), a delay discounting task (hypothetical rewards), a novel future time perception measure, an episodic future thinking (EFT) interview and IQ measures to a sample of 7- to 11-year-olds (N=132) drawn from a urban predominately white population in N. Ireland. We found a strong correlation between delay choice and delay discounting. Future time perception and EFT were related to delay discounting, however only the relation with future time perception survived controlling for age and IQ. Children who showed greater compression of future time periods were the steepest discounters.

93132 Relationship between Level of Response to Alcohol and Body Weight Status in Individuals across the Spectrum of Alcohol Use and Misuse

ABSTRACT IMPACT: Improved understanding of the relationship between level of response to alcohol and body weight in the context of other contributing factors will help inform prevention and intervention efforts regarding obesity. OBJECTIVES/GOALS: We evaluated the association between level of response to alcohol and weight status across the spectrum of alcohol misuse. We hypothesized that lower level of response to alcohol would be associated with heavier weight, after controlling for obesity risk factors like food addiction, impulsivity, and low socioeconomic status. METHODS/STUDY POPULATION: Adult participants (N=587) enrolled in NIAAA’s natural history study completed Self-Rating of the Effects of Alcohol (SRE), a retrospective measure of level of response to alcohol, along with Lifetime Drinking History (LDH); Yale Food Addiction (FA) Scale; Barratt Impulsiveness Scale (BIS); Delayed Discounting Task (DDT). Structured Clinical Interviews for DSM disorders were conducted to identify individuals with current alcohol use disorder (AUD). Body mass index (BMI), computed from height and weight measured during the study, and used to stratify participants into 3 groups: normal weight (N=222), overweight (N=219), or obese (N=146). RESULTS/ANTICIPATED RESULTS: SRE scores during heaviest drinking period were lowest in the heavier weight group, after accounting for FA, impulsivity, alcohol-related, and demographic variables (ê•2=238.5, p=0.002, Cox and Snell Pseudo R2=0.43). Compared to the obese group, normal weight and overweight groups had fewer FA symptoms and higher BIS cognitive complexity (p values&lt;0.01) but similar rates of current AUD. Relative to the obese group, the normal weight group was more likely to be White, and to have lower household incomes but more education, more years of heavy drinking (LDH), and steeper delayed discounting, p values ≤0.03. The overweight group had a higher proportion of males than did the obese group, p&lt;0.001. DISCUSSION/SIGNIFICANCE OF FINDINGS: Lower level of response during heaviest drinking period was significantly associated with current weight status, suggesting a relationship between alcohol sensitivity and BMI. Future work will explore pharmacokinetic-pharmacodynamic and additional risk factors underlying this relationship.

High impulsive choice is accompanied by an increase in dopamine release in rat dorsolateral striatum

Dopamine neurotransmission has been consistently associated with individual differences in impulsive choice. Clinical and preclinical evidence suggests that low striatal dopamine D2 signaling predisposes to engage in impulsive behaviors. Although dopamine D2 signaling controls dopamine (DA) extracellular levels, the relationship between striatal dopamine extracellular levels and impulsive choice remains poorly understood. Using quantitative microdialysis, we investigated whether extracellular DA levels in rat dorsolateral striatum (DLS) correlates with preference for an immediate small reward or for a delayed larger reward. Rats were tested in a delay-discounting task and classified as high impulsive (HI) or low impulsive (LI) according to the area under the discounting curve (AUC). No-net flux microdialysis experiments, assessing basal DA release, DA-uptake, and DA extracellular concentration (DA Cext), were carried out in dorsolateral striatum (DLS) of urethane-anesthetized rats. Rats classified as HI showed a higher DA release compared with LI rats. Differences in DLS DA-uptake and DA Cext were non-significant. Importantly, a significant negative correlation was observed between AUC and DA release, indicating that the lower the AUC, the higher the DLS DA release. This finding shows that DA release is augmented in the DLS of rats classified as HI, suggesting that a hyper-activated nigro-striatal pathway contributes to impulsive choice.

Attachment security, verbal ability, and inhibitory control in middle childhood

BackgroundThe relationship between parent–child attachment and executive function (EF) in middle childhood remains relatively poorly studied. Very little is known about the role that the child’s verbal ability might play in these relationships. Therefore, in the present study, we explored the concurrent links between perceived attachment security with parents and hot and cool inhibitory control (IC)—a core component of EF—as well as the potential mediating role of verbal ability in those links.MethodsThe participants were 160 children aged 8 to 12 (51% girls). They completed the Attachment Security Scale, the computerised version of the go/no-go task, the delay discounting task, and the vocabulary subtest from the Wechsler Intelligence Scale for Children. Pearson’s correlations were conducted to test relationships between the study variables. A hierarchical multiple linear regression analysis was performed to examine whether attachment security uniquely contributed to the outcomes after accounting for covariates. The indirect effects were tested using a non-parametric resampling bootstrap approach.ResultsThe results showed that, after accounting for the child’s age and sex, there was a direct relationship between attachment security with the father and cool, but not hot, IC. However, there were no significant links between attachment security with the mother and both aspects of IC. We also found that children’s verbal ability played a mediating role in the associations between both child–father and child–mother attachment security and hot, but not cool, IC above and beyond the child’s age.ConclusionsThe current study extends previous work on executive functions in middle childhood. The results highlight the role of attachment in explaining individual differences in IC in middle childhood as well as the different mechanisms through which attachment with parents might explain cool vs. hot IC. The findings have potential implications for therapeutic interventions using the family context as a target to improve IC in middle childhood.