Using Demand Curves to Quantify the Reinforcing Value of Social and Solitary Drinking

Contextual and psychosocial factors influencing drug reward in humans: The importance of non-drug reinforcement

The reinforcing efficacy, or behavior-strengthening effect, of a substance is a critical determinant of substance use typically quantified by measuring behavioral allocation to the substance under schedules of reinforcement with escalating response requirements. Although responses on these tasks are often used to indicate stable reinforcing effects or trait-level abuse potential for an individual, task designs often demonstrate within-person variability across varying degrees of a constraint within experimental procedures. As a result, quantifying behavioral allocation is an effective approach for measuring the impact of contextual and psychosocial factors on substance reward. We review studies using laboratory self-administration, behavioral economic purchase tasks, and ambulatory assessments to quantify the impact of various contextual and psychosocial factors on behavioral allocation toward consumption of a substance. We selected these assessment approaches because they cover the translational spectrum from experimental control to ecological relevance, with consistent support across these approaches representing greater confidence in the effect. Conceptually, we organized factors that influence substance value into two broad categories: factors that influence the cost/benefit ratio of the substance (social context, stress and affect, cue exposure), and factors that influence the cost/benefit ratio of an alternative (alternative non-drug reinforcers, alternative drug reinforcers, and opportunity costs). We conclude with an overview of future research directions and considerations for clinical application.

Correspondence between the alcohol-P3 event-related potential and alcohol reward phenotypes among young adults

BACKGROUND

Behavioral economic theory suggests that the value of alcohol depends upon elements of the choice context, such that increasing constraints on alternatives (e.g., price) or increasing the benefits of alcohol (e.g., social context) may result in greater likelihood of heavy drinking. The P3 event-related potential elicited by alcohol-related cues, a proposed marker of incentive salience, may be an electrophysiological parallel for behavioral economic alcohol demand. However, these indices have not been connected in prior research, and studies typically do not disaggregate social influences in the context of alcohol cue reactivity.

METHOD

The current study recruited heavy drinking young adults (N = 81) who completed measures of alcohol use and alcohol demand, in addition to a 2 (social/nonsocial) × 2 (alcohol/nonalcohol) visual oddball task to elicit the P3.

RESULTS

In multilevel models controlling for demographic characteristics, P3 reactivity was greater to alcohol (p < 0.001) and social (p < 0.001) cues than to nonalcohol and nonsocial cues, but without a significant interaction. Higher alcohol consumption (p = 0.02) and lower elasticity of demand (p = 0.01) were associated with greater P3 response to alcohol than nonalcohol cues.

CONCLUSIONS

The results highlight a brain-behavior connection that may be an important marker for alcohol reward across units of analysis and may be sensitive to changes in the economic choice contexts that influence the likelihood of alcohol use.

Alcohol cues increase behavioral economic demand and craving for alcohol in nontreatment-seeking and treatment-seeking heavy drinkers

BACKGROUND

Behavioral economic research has revealed significant increases in alcohol demand following exposure to alcohol-related cues. Prior research has focused exclusively on nontreatment-seeking heavy drinkers, included only male participants, or used heterogeneous methods. The current studies sought to replicate and extend existing findings in treatment-seeking and nontreatment-seeking heavy drinkers while also examining sex effects and moderation by alcohol use disorder (AUD) severity.

METHODS

Study 1 included 117 nontreatment-seeking heavy drinkers (51.5% women; M age 34.69; 56.4% AUD+), and Study 2 included 89 treatment-seeking heavy drinkers with AUD (40.4% women; M age = 41.35). In both studies, alcohol demand was measured using a hypothetical alcohol purchase task (APT), and subjective alcohol craving was measured using visual analog scales. Measures were collected following exposure to neutral (water) cues in a standard room and alcohol cues in a bar lab.

RESULTS

Alcohol demand (intensity, Omax , breakpoint, and elasticity) and craving were significantly increased following alcohol cues compared to neutral cues (ps < 0.005) with effect sizes ranging from small to large (ηp 2  = 0.074-0.480). Participants with AUD (Study 1) or with higher AUD severity (Study 2) reported higher craving and higher demand for most indices (i.e., main effects; ps < 0.032, ηp 2  = 0.043-0.239). A larger alcohol cue increase in Omax was found for AUD+ participants in Study 1 compared to non-AUD participants (p = 0.028, ηp 2  = 0.041) but not for any other indices in Study 1 or Study 2. There were no significant sex effects.

CONCLUSIONS

These findings replicate and extend prior research by offering additional insight into alcohol cue effects on the reinforcing value of alcohol and subjective motivation to drink. The results also suggest that sex and AUD severity do not meaningfully impact cue effects across most indices of demand.

Role of social context in addiction etiology and recovery

While social context has long been considered central to substance use disorder prevention and treatment and many drug-taking events occur in social settings, experimental research on social context has historically been limited. Recent years have seen an emergence of concerted preclinical and human laboratory research documenting the direct impact of social context on substance use, delineating behavioral and neurobiological mechanisms underlying social influence's role. We review this emerging preclinical and human laboratory literature from a theoretical lens that considers distinct stages of the addiction process including drug initiation/acquisition, escalation, and recovery. A key conclusion of existing research is that the impact of the social environment is critically moderated by the drug-taking behavior and drug use history of a social peer. Specifically, while drug-free social contexts can reduce the likelihood of drug use initiation and act as a competitive non-drug alternative preventing escalation, drug-using peers can equally facilitate initiation and escalation through peer modeling as a contingent reward of use. Likewise, social context may facilitate recovery or serve as a barrier that increases the chances of a return to regular use. We conclude by discussing evidence-based treatments and recovery support services that explicitly target social mechanisms or that have identified social context as a mechanism of change within treatment. Ultimately, new areas for research including the expansion of drug classes studied and novel human laboratory designs are needed to further translate emerging findings into clinical practice.

The Role of Environmental Context and Physical Activity in Prescribed Opioid Use and Pain in Daily Life among Patients With Chronic Low Back Pain

BACKGROUND

Prescription opioids remain a primary treatment option for patients with chronic low back pain. However, little research has examined how patients take opioids in daily life. Behavioral economics suggest that the environmental context may contribute to patients' decisions around opioid use.

PURPOSE

This study examined the association of self-reported environmental factors and physical activity with likelihood of taking opioids, opioid dosage, and physical pain.

METHOD

Patients with chronic low back pain on long-term opioid therapy (n = 34) without significant past-year opioid-related problems completed a two-week ecological momentary assessment protocol (nobservations = 1,714).

RESULTS

Initial multilevel models revealed multiple associations for different specific contexts with opioid use and pain. In models that collapsed specific contexts into categories (where, with whom, doing what), greater occasion-level physical activity was associated with a greater likelihood of taking opioids and greater pain, and being somewhere (v. at home) was associated with taking a smaller opioid dose. At any given occasion, being with someone (v. alone) was associated with taking a larger opioid dose, but patients who spent more time with others over the entire study took fewer opioids overall. Multilevel mediation found that pain did not mediate the association of physical activity and opioid use.

CONCLUSION

Results suggest that prescribed opioid use in patients with chronic low back pain is not solely determined by pain, but influenced by environmental factors, including physical activity. Psychoeducation regarding environmental factors, including how factors may be associated with both increased and decreased use of opioids, may help patients take fewer opioids more effectively.

A contextualized reinforcer pathology approach to addiction

Behavioural economic accounts of addiction conceptualize harmful drug use as an operant reinforcer pathology, emphasizing that a drug is consumed because of overvaluation of smaller immediate rewards relative to larger delayed rewards (delay discounting) and high drug reinforcing value (drug demand). These motivational processes are within-individual determinants of behaviour. A third element of learning theory posits that harmful drug use depends on the relative constraints on access to other available activities and commodities in the choice context (alternative reinforcers), reflecting the substantial influence of environmental factors. In this Perspective, we integrate alternative reinforcers into the contemporary behavioural economic account of harmful drug use - the contextualized reinforcer pathology model - and review empirical literature across the translational spectrum in support of this model. Furthermore, we consider how increases in drug-related mortality and health disparities in addiction can be understood and potentially ameliorated via a contextualized reinforcer pathology model in which lack of alternative reinforcement is a major risk factor for addiction.

The effects of social context and opportunity cost on the behavioral economic value of cannabis

OBJECTIVE

Behavioral economics suggest that cannabis reinforcing value (cannabis demand) may be influenced by external, contextual factors such as the social reward that might accompany cannabis use and the presence of opportunity costs (e.g., a next-day responsibility that cannabis use might adversely impact). The present study examined the effect of social context and opportunity cost on cannabis demand and explored whether relations were moderated by cannabis use severity.

METHOD

Adults with past-week cannabis use recruited from Amazon's Mechanical Turk (N = 310; 53.5% female, 79.4% White) completed four purchase tasks, in which participants reported how much cannabis they would purchase across escalating prices, to index cannabis demand under varying contexts: (a) solitary, typical responsibilities; (b) social, typical responsibilities; (c) solitary, substantial responsibilities; and (d) social, substantial responsibilities.

RESULTS

The presence of peers significantly increased demand intensity (consumption at zero price) and Omax (maximum expenditure) relative to the solitary conditions. Substantial responsibilities significantly decreased intensity, breakpoint (price at which consumption is fully suppressed), and Pmax (price at which maximum expenditure occurs) and increased elasticity (greater price sensitivity). Demand was most inelastic in the social, typical responsibilities condition relative to other conditions. Cannabis use severity was associated with less elastic demand in the solitary, typical responsibilities condition. Those with higher cannabis use severity reported larger differences in demand intensity and Omax between solitary and social conditions, and in demand elasticity between typical and substantial responsibility conditions.

CONCLUSIONS

Results are consistent with previous research illustrating social and opportunity costs as determinants of cannabis use behavior. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Reinforcer pathology of internet-related behaviors among college students: Data from six countries

Research has demonstrated that repeated engagement in low-effort behaviors that are associated with immediate reward, such as Internet use, can result in a pathological reinforcement process in which the behavior is increasingly selected over other activities due, in part, to a low availability of alternative activities and to a strong preference for immediate rather than delayed rewards (delay discounting). However, this reinforcer pathology model has not been generalized to other Internet-related behaviors, such as online gaming or smartphone use. Given the widespread availability of these technologies, it is also important to examine whether reinforcer pathology of Internet-related behaviors is culturally universal or culture-specific. The current study examines relations between behavioral economic constructs (Internet demand, delay discounting, and alternative reinforcement) and Internet-related addictive behaviors (harmful Internet use, smartphone use, online gaming, and Internet sexual behavior) in a cross-sectional sample of college students (N = 1,406) from six different countries (Argentina, Australia, India, Malaysia, the United Kingdom, and the United States). Using structural equation modeling, Internet demand was associated with harmful Internet use, smartphone use, and online gaming; delay discounting was associated with harmful smartphone use; and alternative reinforcement was associated with harmful Internet and smartphone use. The models were partially invariant across countries. However, mean levels of behavioral economic variables differed across countries, country-level gross domestic product, person-level income, and sex at birth. Results support behavioral economic theory and highlight the importance of considering both individual and country-level sociocultural contextual factors in models for understanding harmful engagement with Internet-related behaviors. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

(Non-) impact of task experience on behavioral economic decision-making

Behavioral economic research has been widely conducted via crowdsourcing resources to evaluate novel task designs or pilot interventions. One under recognized and yet-to-be tested concern is the impact of non-naïvety (i.e., prior task exposure) on behavioral economic task performance. We evaluated the influence of non-naïvety on task performance in two popular areas of behavioral economic research: behavioral economic demand and delay discounting. Participants (N = 485) recruited using Amazon Mechanical Turk (mTurk) completed alcohol and soda purchase tasks and delay discounting tasks for monetary and alcohol outcomes. Equivalence of responding and effect sizes with clinical variables were compared based on prior task experience. Over one quarter of participants reported demand task experience (26.9%) and nearly half endorsed delay discounting task experience (48.6%). Statistically equivalent responding was observed for alcohol purchase task data with less-than-small effect size differences based on task experience (d = 0.01-0.13). Similar results were observed for a soda purchase task thereby supporting generalization to a non-alcohol commodity. Measures of convergent and discriminant validity for behavioral economic demand indicated medium-to-large and stimulus-specific effect sizes with little variation based on prior task exposure. Delay discounting for money and alcohol showed some sensitivity to prior task experience (i.e., less steep discounting for non-naïve participants), however these effects were attenuated after accounting for group differences in alcohol use. These findings support the fidelity of behavioral economic task outcomes and emphasize that participant non-naïvety in crowdsourcing settings may minimally impact performance on behavioral economic assays commonly used in behavioral and addiction science. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Behavioral economics of substance use: Understanding and reducing harmful use during the COVID-19 pandemic

Behavioral economic research demonstrates that alcohol and drug consumption is (a) an inverse function of constraints on access to the substance and (b) a direct function of constraints on access to alternative rewards. Physical distancing interventions and economic consequences of the COVID-19 pandemic have resulted in unprecedented reductions in many of the constraints on substance use and in critical evolutionarily salient sources of alternative reward, such as social interaction, physical activity, leisure activities and hobbies, and academic and occupational pursuits. Thus, behavioral economics suggests that the pandemic and necessary public health response have created a "perfect storm" for exacerbation of individual-level and population-level substance use problems and also points to multilevel intervention strategies. We summarize this perspective and research by highlighting 3 critical behavioral processes that will influence drug and alcohol consumption. First, the sudden absence of many effective constraints on substance use (work, school, community, or service obligations) will reduce the actual and perceived cost of use. Second, physical distancing measures will reduce the availability, and increase the cost, of many rewarding substance-free activities and commodities. Third, increased uncertainty around current and future events increases discounting of delayed rewards. These effects will be especially pernicious among populations with existing health disparities. Next, we outline interventions suggested by behavioral economics to mitigate the impact of COVID-19 on substance use that are aimed at increasing perceived costs of use; increasing access to substance-free activities, including treatment; and lengthening the timeframe for behavioral allocation and altering environmental contexts to promote healthy choices. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

At-Risk Drinking, Operant Demand, and Cross-Commodity Discounting as Predictors of Drunk Driving in Underage College Women

Behavioral economics offers unique tools for assessing value and motivation associated with college drinking. Tasks that model changes in consumption as a function of price (operant demand) or the decline in an outcome's subjective value as a function of time-to-occurrence (delay discounting) provide valuable information that may efficiently supplement clinical screening instruments when characterizing alcohol use severity. The first aim of this investigation was to examine the extent to which at-risk drinking, operant demand for alcohol, and single- and cross-commodity discounting of money and alcohol predict adverse consequences of past-month drinking in underage college women (N = 72). The second aim was to determine whether these clinical and behavioral economic measures could significantly predict the odds of past-month drunk driving, a serious public health concern due to the increasing prevalence of heavy episodic drinking among women in their first 1 - 2 years of college. Results showed that higher scores on the consumption factor of the Alcohol Use Disorder Identification Test (AUDIT-C), greater Persistence (consumption amidst constraint) and Amplitude (maximum consumption) of demand, as well as lower rates of discounting for choices between receiving alcohol now or double the amount after a delay (choosing the larger amount of alcohol even when it is delayed) significantly predicted adverse consequences of past-month drinking. Moreover, scores on the AUDIT-C, Amplitude of demand, and higher rates of discounting for choices between receiving alcohol now and money later (choosing immediately available alcohol at the expense of double the equivalent in delayed money) significantly predicted past-month drunk driving. We contend that operant demand along with single- and cross-commodity discounting can be viewed as intersecting measures of reinforcer value with clinical relevance to college women.

Concurrent validity of the Alcohol Purchase Task for measuring the reinforcing efficacy of alcohol: an updated systematic review and meta-analysis

BACKGROUND AND AIMS

An early meta-analysis testing the concurrent validity of the Alcohol Purchase Task (APT), a measure of alcohol's relative reinforcing value, reported mixed associations, but predated a large number of studies. This systematic review and meta-analysis sought to: (1) estimate the relationships between trait-based alcohol demand indices from the APT and multiple alcohol indicators, (2) test several moderators and (3) analyze small study effects.

METHODS

A meta-analysis of 50 cross-sectional studies in four databases (n = 18 466, females = 43.32%). Sex, year of publication, number of APT prices and index transformations (logarithmic, square root or none) were considered as moderators. Small study effects were examined by using the Begg-Mazumdar, Egger's and Duval & Tweedie's trim-and-fill tests. Alcohol indicators were quantity of alcohol use, number of heavy drinking episodes, alcohol-related problems and hazardous drinking. APT indices were intensity (i.e. consumption at zero cost), elasticity (i.e. sensitivity to increases in costs), O_max (i.e. maximum expenditure), P_max (i.e. price associated to O_max ) and breakpoint (i.e. price at which consumption ceases).

RESULTS

All alcohol demand indices were significantly associated with all alcohol-related outcomes (r = 0.132-0.494), except P_max , which was significantly associated with alcohol-related problems only (r = 0.064)_. The greatest associations were evinced between intensity in relation to alcohol use, hazardous drinking and heavy drinking and between O_max and alcohol use. All the tested moderators emerged as significant moderators. Evidence of small-study effects was limited.

CONCLUSIONS

The Alcohol Purchase Task appears to have concurrent validity in alcohol research. Intensity and O_max are the most relevant indices to account for alcohol involvement.

Behavioral economics and the aggregate versus proximal impact of sociality on heavy drinking

BACKGROUND

Behavioral economic theory predicts decisions to drink are cost benefit analyses, and heavy episodic drinking occurs when benefits outweigh costs. Social interaction is a known benefit associated with alcohol use. Although heavy drinking is typically considered more likely during more social drinking events, people who drink heavily in isolation tend to report greater severity of use. This study explicitly disaggregates between-person and within-person effects of sociality on heavy episodic drinking and examines behavioral economic moderators.

METHODS

We used day-level survey data over an 18-week period in a community adult sample recruited through crowdsourcing (mTurk; N = 223). Behavioral economic indices were examined to determine if macro person-level variables (alcohol demand, delay discounting, proportionate alcohol-related reinforcement [R-ratio]) interact with event-level social context to predict heavy drinking episodes.

RESULTS

Mixed effect models indicated significant between-person and within-person social context associations. Specifically, people with a higher proportion of total drinking occasions in social contexts had decreased odds of heavy drinking, whereas being in a social context for a specific drinking occasion was associated with increased odds of heavy drinking. Person-level R-Ratio, demand elasticity, and breakpoint variables interacted with social context to predict heavy episodic drinking, such that the event-level social context association was stronger when R-Ratios, alcohol price insensitivity, and demand breakpoints were high.

CONCLUSIONS

These results demonstrate an ecological fallacy, in which the size and direction of effects were divergent at different levels of analysis, and highlight the potential for merging behavioral economic variables with proximal contextual effects to predict heavy drinking.

Associations between the Brief Assessment of Alcohol Demand (BAAD) questionnaire and alcohol use disorder severity in UK samples of student and community drinkers

Value based choice and compulsion theories of addiction offer distinct explanations for the persistence of alcohol use despite harms. Choice theory argues that problematic drinkers ascribe such high value to alcohol that costs are outweighed, whereas compulsion theory argues that problematic drinkers discount costs in decision making. The current study evaluated these predictions by testing whether alcohol use disorder (AUD) symptom severity (indexed by the AUDIT) was more strongly associated with the intensity item (maximum alcohol consumption if free, indexing alcohol value) compared to the breakpoint item (maximum expenditure on a single drink, indexing sensitivity to monetary costs) of the Brief Assessment of Alcohol Demand (BAAD) questionnaire, in student (n = 579) and community (n = 120) drinkers. The community sample showed greater AUD than the student sample (p = .004). In both samples, AUD severity correlated with intensity (students, r = 0.63; community, r = 0.47), but not with breakpoint (students, r = -0.01; community, r = 0.12). Similarly, multiple regression analyses indicated that AUD severity was independently associated with intensity (student, ΔR² < 0.20, p < .001; community, ΔR² = 0.09, p = .001) but not breakpoint (student, ΔR² = 0.003, p = .118; community ΔR² = 0.01, p = .294). There was no difference between samples in the strength of these associations. The value ascribed to alcohol may play a more important role in AUD severity than discounting of alcohol-associated costs (compulsivity), and there is no apparent difference between student and community drinkers in the contribution of these two mechanisms.

Depression, Environmental Reward, Coping Motives and Alcohol Consumption During the COVID-19 Pandemic

Background: Increases in the incidence of psychological distress and alcohol use during the COVID-19 pandemic have been predicted. Behavioral theories of depression and alcohol self-medication theories suggest that greater social/environmental constraints and increased psychological distress during COVID-19 could result in increases in depression and drinking to cope with negative affect. The current study had two goals: (1) to examine self-reported changes in alcohol use and related outcomes after the introduction of COVID-19 social distancing requirements, and; (2) to test hypothesized mediation models to explain individual differences in self-reported changes in depression and alcohol use during the early weeks of the COVID-19 pandemic. Methods: Participants (n = 833) were U.S. residents recruited for participation in a single online survey. The cross-sectional survey included questions assessing environmental reward, depression, COVID-19-related distress, drinking motives, and alcohol use outcomes. Outcomes were assessed via retrospective self-report for two timeframes in the single survey: the 30 days prior to state-mandated social distancing ("pre-social-distancing"), and the 30 days after the start of state-mandated social distancing ("post-social-distancing"). Results: Depression severity, coping motives, and some indices of alcohol consumption (e.g., frequency of binge drinking, and frequency of solitary drinking) were significantly greater post-social-distancing relative to pre-social-distancing. Conversely, environmental reward and other drinking motives (social, enhancement, and conformity) were significantly lower post-social distancing compared to pre-social-distancing. Behavioral economic indices (alcohol demand) were variable with regard to change. Mediation analyses suggested a significant indirect effect of reduced environmental reward with drinking quantity/frequency via increased depressive symptoms and coping motives, and a significant indirect effect of COVID-related distress with alcohol quantity/frequency via coping motives for drinking. Discussion: Results provide early cross-sectional evidence regarding the relation of environmental reward, depression, and COVID-19-related psychological distress with alcohol consumption and coping motives during the early weeks of the COVID-19 pandemic. Results are largely consistent with predictions from behavioral theories of depression and alcohol self-medication frameworks. Future research is needed to study prospective associations among these outcomes.

Relative expected value of drugs versus competing rewards underpins vulnerability to and recovery from addiction

Behavioural economic theories of addiction contend that greater expected value of drug relative to alternative non-drug rewards is the core mechanism underpinning vulnerability to and recovery from addiction. To evaluate this claim, we exhaustively review studies with human drug users that have measured concurrent choice between drugs vs. alternative rewards, and explored individual differences. These studies show that drug choice can be modulated by drug cues, drug devaluation, imposition of costs/punishment and negative mood induction. Regarding individual differences, dependence severity was reliably associated with overall drug preference, and self-reported drug use to cope with negative affect was reliably associated with greater sensitivity to mood induced increases in drug choice. By contrast, there were no reliable individual differences in sensitivity to the effect of drug cues, drug devaluation or punishment on drug choice. These findings provide insight into the mechanisms that underpin vulnerability to dependence: vulnerability is conferred by greater relative value ascribed to drugs, and relative drug value is further augmented by negative affective states in those who report drug use coping motives. However, dependence does not appear to be characterised by abnormal cue-reactivity, habit learning or compulsion. We then briefly review emerging literature which demonstrates that therapeutic interventions and recovery from addiction might be attributed to changes in the expected relative value of drug versus alternative rewards. Finally, we outline a speculative computational account of the distortions in decision-making that precede action selection in addiction, and we explain how this account provides a blueprint for future research on the determinants of drug choice, and mechanisms of treatment and recovery from addiction. We conclude that a unified economic decision-making account of addiction has great promise in reconciling diverse addiction theories, and neuropsychological evaluation of the underlying decision mechanisms is a fruitful area for future research and treatment.