Validation of a brief behavioral economic assessment of demand among cigarette smokers

Prefrontal-Limbic Circuitry Is Associated With Reward Sensitivity in Nonhuman Primates

BACKGROUND

Abnormal reward sensitivity is a risk factor for psychiatric disorders, including eating disorders such as overeating and binge-eating disorder, but the brain structural mechanisms that underlie it are not completely understood. Here, we sought to investigate the relationship between multimodal whole-brain structural features and reward sensitivity in nonhuman primates.

METHODS

Reward sensitivity was evaluated through behavioral economic analysis in which monkeys (adult rhesus macaques; 7 female, 5 male) responded for sweetened condensed milk (10%, 30%, 56%), Gatorade, or water using an operant procedure in which the response requirement increased incrementally across sessions (i.e., fixed ratio 1, 3, 10). Animals were divided into high (n = 6) or low (n = 6) reward sensitivity groups based on essential value for 30% milk. Multimodal magnetic resonance imaging was used to measure gray matter volume and white matter microstructure. Brain structural features were compared between groups, and their correlations with reward sensitivity for various stimuli was investigated.

RESULTS

Animals in the high sensitivity group had greater dorsolateral prefrontal cortex, centromedial amygdaloid complex, and middle cingulate cortex volumes than animals in the low sensitivity group. Furthermore, compared with monkeys in the low sensitivity group, high sensitivity monkeys had lower fractional anisotropy in the left dorsal cingulate bundle connecting the centromedial amygdaloid complex and middle cingulate cortex to the dorsolateral prefrontal cortex, and in the left superior longitudinal fasciculus 1 connecting the middle cingulate cortex to the dorsolateral prefrontal cortex.

CONCLUSIONS

These results suggest that neuroanatomical variation in prefrontal-limbic circuitry is associated with reward sensitivity. These brain structural features may serve as predictive biomarkers for vulnerability to food-based and other reward-related disorders.

Behavioral economic analysis of legal and illegal cannabis demand in Spanish young adults with hazardous and non-hazardous cannabis use

BACKGROUND

In October 2021, a legal framework that regulates cannabis for recreational purposes in Spain was proposed, but research on its potential impacts on cannabis use is currently limited. This study examined the reliability and discriminant validity of two Marijuana Purchase Tasks (MPTs) for measuring hypothetical legal and illegal cannabis demand, and to examine differences in demand of both commodities in young adults at hazardous vs. non-hazardous cannabis use risk levels.

METHODS

A total of 171 Spanish young adults [Mage = 19.82 (SD = 1.81)] with past-month cannabis use participated in a cross-sectional study from September to November 2021. Two 27-item MPTs were used to estimate hypothetical demand for legal and illegal cannabis independently. The Cannabis Use Disorder Identification Test (CUDIT-R) was used to assess hazardous cannabis use and test for discriminant validity of the MPTs. Reliability analyses were conducted using Classical Test Theory (Cronbach's alpha) and Item Response Theory (Item Information Functions).

RESULTS

The MPT was reliable for measuring legal (α = 0.94) and illegal (α = 0.90) cannabis demand. Breakpoint (price at which demand ceases), and Pmax (price associated with maximum expenditure) were the most sensitive indicators to discriminate participants with different levels of the cannabis reinforcing trait. No significant differences between legal and illegal cannabis demand in the whole sample were observed, but hazardous vs. non-hazardous users showed higher legal and illegal demand, and decreased Breakpoint and Pmax if cannabis were legal vs illegal.

CONCLUSION

The MPT exhibits robust psychometric validity and may be useful to inform on cannabis regulatory science in Spain.

Presentation matters: Effects of cigarette purchase task design on systematic data and purchasing behavior

Hypothetical purchase tasks (HPTs) are effective tools for evaluating participants' demand for substances. The present study evaluated the effect of task presentation on producing unsystematic data and purchasing behavior in a sample of individuals who smoke cigarettes. Participants (n = 365) were recruited from Amazon Mechanical Turk and randomly assigned to complete two of three HPT presentations: List (prices on one page in an increasing order), Ascending (one price per page in an increasing order), or Random (one price per page in a random order). We evaluated outcomes using a mixed model regression with a random effect for participants. We observed a significant effect of task presentation on passing the criterion assessing consistency in effects of contiguous prices (i.e., Bounce; X²(2) = 13.31, p = .001). A significant effect of task presentation on Trend or Reversals from Zero was not observed. For purchasing behavior, we observed a significant effect of task presentation on R², X²(2) = 17.89, p < .001; BP₁, X²(2) = 13.64, p = .001; ln(α), X²(2) = 332.94, p < .001; and ln(Omax), X²(2) = 20.26, p < .001; we did not observe a significant effect of task presentation on ln(Q₀) or ln(Pmax). We recommend against using the Random HPT presentation to avoid unsystematic data. While the List and Ascending presentations do not differ across unsystematic criteria or purchasing behavior, the List presentation may be preferred due to participant experience. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Initial development and validation of a brief assessment of marijuana demand among young adult college students

Hypothetical purchase tasks assess substance demand, but the length of purchase tasks makes repeated assessment of state-dependent changes in demand difficult, often limiting clinical utility. Although brief assessments of alcohol and cigarette demand exist, brief measures of cannabis demand do not. College students (N = 209, Mage = 19.92, SD = 1.45; 63% female; 56.9% non-Hispanic Caucasian) who reported using cannabis at least 3 days in the past month, completed an online survey including the full-length marijuana purchase task (MPT), a three-item brief assessment of marijuana demand (BAMD) assessing intensity, Omax and breakpoint, and cannabis use outcomes. Convergent and divergent validity were examined. Independent samples t tests compared demand on the BAMD and MPT based on presence or absence of cannabis use disorder (CUD) symptoms, and one-way between-subject analyses of variance compared effects of CUD severity (mild/moderate/severe) on BAMD indices. All indices were significantly correlated across both assessment measures (ps < .01). Similarly, all indices on both demand measures were significantly correlated with craving, CUD severity, and cannabis-related consequences (ps < .01); whereas only intensity and Omax were significantly correlated with cannabis use frequency (ps < .01). Individuals with (vs. without) CUD symptoms reported significantly greater intensity and Omax (ps < .01) and significant differences in CUD severity on BAMD indices were found as well (ps < .05). The BAMD demonstrated convergent and divergent validity with the MPT. Findings suggest that brief cannabis demand can be easily assessed as an indicator for high-risk cannabis use. Thus, the BAMD may be a useful and clinically relevant tool to assess cannabis demand in real-world settings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Validation of the Food Purchase Task (FPT) in a clinical sample of smokers with overweight and obesity

Obesity is a major health problem associated with disease burden and mortality. In this context, analyzing food as a powerful reinforcer from a behavioral economics framework could be relevant for the treatment and prevention of obesity. The purposes of this study were to validate a food purchase task (FPT) in a clinical sample of Spanish smokers with overweight and obesity and to assess the internal structure of the FPT. We also analyzed the clinical utility of single-item breakpoint (i.e., commodity price that suppresses demand). A total of 120 smokers [% females: 54.2; M_age = 52.54; SD = 10.34] with overweight and obesity completed the FPT and weight/eating-related variables. Principal component analysis was used to examine the FPT structure, and a set of correlations were used to examine the relationship between the FPT, eating and weight-related variables. The FPT demonstrated robust convergent validity with other measures of eating. Higher food demand was related to higher food craving (r = .33), more binge eating problems (r = 0.39), more weight gain concerns (r = 0.35), higher frequency of both controlled (r = 0.37) and uncontrolled (r = 0.30) grazing, as well as to an eating style in response to emotions (r = 0.34) and external eating (r = 0.34). Of the demand indices, Intensity and O_max showed the highest magnitudes of effects. The FPT factors, persistence and amplitude, do not improve individual FPT indices; and the single-item breakpoint was not related to any eating or weight variable. The FPT is a valid measure of food reinforcement with potential clinical utility in smokers with obesity/overweight.

Rate-dependent effects of narrative interventions in a longitudinal study of individuals who use alcohol

BACKGROUND

Delay discounting (DD), the decrease in reward valuation as a function of delay to receipt, is a key process undergirding alcohol use. Narrative interventions, including episodic future thinking (EFT), have decreased delay discounting and demand for alcohol. Rate dependence, the relationship between a baseline rate and change in that rate after an intervention, has been evidenced as a marker of efficacious substance use treatment, but whether narrative interventions have rate-dependent effects needs to be better understood. We investigated the effects of narrative interventions on delay discounting and hypothetical demand for alcohol in this longitudinal, online study.

METHODS

Individuals (n = 696) reporting high- or low-risk alcohol use were recruited for a longitudinal 3-week survey via Amazon Mechanical Turk. Delay discounting and alcohol demand breakpoint were assessed at baseline. Individuals returned at weeks 2 and 3 and were randomized into the EFT or scarcity narrative interventions and again completed the delay discounting tasks and alcohol breakpoint task. Oldham's correlation was used to explore the rate-dependent effects of narrative interventions. Study attrition as a function of delay discounting was assessed.

RESULTS

Episodic future thinking significantly decreased, while scarcity significantly increased delay discounting relative to baseline. No effects of EFT or scarcity on the alcohol demand breakpoint were observed. Significant rate-dependent effects were observed for both narrative intervention types. Higher delay discounting rates were associated with a greater likelihood of attrition from the study.

CONCLUSION

The evidence of a rate-dependent effect of EFT on delay discounting rates offers a more nuanced, mechanistic understanding of this novel therapeutic intervention and can allow more precise treatment targeting by demonstrating who is likely to receive the most benefit from it.

Examining the latent factor structure of a hypothetical cigarette purchase task among pregnant women

The cigarette purchase task (CPT) is a valid behavioral-economic measure of demand that has smokers estimate hypothetical cigarette consumption under a range of escalating prices. The task involves no experimenter exposure of participants to smoking. CPT demand is measured in terms of five indices: intensity (cigarettes consumed at $0), Omax (largest expenditure), Pmax (price associated with peak expenditure), breakpoint (the first price at which consumption is 0), and elasticity (rate at which consumption changes as a function of increasing price). Out of concern for collinearity, prior studies investigated a more parsimonious CPT latent-factor structure for these derived indices consisting of two factors. The present study examined whether the same two latent-factor solutions extend to pregnant women who smoke. Six hundred sixty-five women completed the CPT as part of recruitment for a clinical trial examining the efficacy of a remote contingency-management intervention to promote smoking cessation during pregnancy. Factor analysis confirmed a two-factor solution to the CPT accounting for 87% of the variance in the five indices with demand intensity and Omax loading onto amplitude and Omax, Pmax, breakpoint, and elasticity loading onto persistence. Backward elimination regression revealed a significant negative relationship between amplitude and persistence (i.e., lower amplitude and persistence scores predicted a higher likelihood of making at least one quit attempt upon learning of pregnancy). These results further support the utility of the CPT for experimentally examining individual differences in smoking among pregnant women in an efficient and ethical manner that does not involve exposing them to cigarette smoke. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Alcohol demand and supersized alcopop consumption among undergraduate college students

Supersized alcopops are sugar-sweetened beverages with extraordinarily high alcohol content; consumption is highly prevalent among college students and is associated with a variety of negative alcohol-related consequences. However, few studies have examined risk factors for consumption of these products. The objective of this study was to examine, among a college student sample, whether the behavioral economic principle of alcohol demand was associated with self-reported lifetime consumption of Four Loko-the most popular brand of supersized alcopop among underage drinkers. Participants were 170 undergraduate students who were at least 18 years of age and reported at least 1 day of alcohol consumption within the past month. Study participants completed a self-administered questionnaire assessing demographics, Four Loko consumption and associated problems, and alcohol demand (using the Brief Assessment of Alcohol Demand). Hierarchical logistic regression analyses revealed that intensity (drinks they would consume if free) significantly predicted Four Loko consumption but not breakpoint (maximum expenditure per drink) or Omax (maximum expenditure for all drinks). Findings support that students who prefer consuming large quantities of alcohol when it is free are more likely to have consumed Four Loko. Interventions increasing price or reducing the availability of Four Loko may be especially protective for this at-risk population. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

No evidence of the clinical utility of single-item breakpoint to inform on tobacco demand in persons with substance use disorders

RATIONALE

Behavioral economics has shown that single-item demand indicators are promising for capturing crucial aspects of nicotine reinforcement. It is suggested that brief breakpoint measures perform comparably to full-length demand indices in characterizing nicotine dependence; however, there have been no thorough assessments of their validity in clinical settings.

OBJECTIVES

This study aimed to assess the validity and accuracy of a single-item breakpoint in informing on tobacco demand.

METHODS

The sample consisted of 88 treatment-seeking smokers (% males = 70.5%) enrolled in substance use treatment. Participants provided data on smoking characteristics and completed the Fagerström Test for Nicotine Dependence, a single-item breakpoint measure and a 14-item cigarette purchase task (CPT). Hierarchical regressions were performed to compare the predictive capability of a single-item breakpoint and full-length tobacco demand indicators in determining nicotine addiction severity.

RESULTS

The single-item breakpoint was significantly correlated with all indices stemmed from the CPT and both latent factors (all r values = .250-.368). Neither the brief breakpoint nor the full-length breakpoint significantly predicted nicotine dependence. After controlling for sex and smoking variables, factor 2 [β = .565, p < .001] and its observed variables Omax [β = .279, p = .006], 1/elasticity [β = .340, p = .001], and intensity [β = .551, p < .001], robustly predicted nicotine dependence severity.

CONCLUSIONS

Our findings do not support the validity of single-item breakpoint measures for characterizing nicotine dependence in substance users. In a bid to foster translational research, brief demand measures capturing Omax, intensity, and elasticity should be developed.

Initial development of a brief assessment of cocaine demand

Cocaine demand is a behavioral economic measure assessing drug reward value and motivation to use drug. The purpose of the current study was to develop a brief assessment of cocaine demand (BACD). Results from the BACD were compared with self-report measures of cocaine use. Participants consisted of treatment-seeking individuals with cocaine use disorder (N = 22). Results revealed that indices of brief demand were significantly associated with various self-report measures of cocaine use. Overall, these results support the utility of a BACD for assessing cocaine demand.

Narrative theory III: Evolutionary narratives addressing mating motives change discounting and tobacco valuation

Relationships between discounting and addictive behaviors have both state- and trait-based components. Evolutionarily driven motives may trigger risk-taking behaviors, and narratives might be used to alter the temporal window of reward valuation. The current investigation-in 2 separate studies-sought to understand the basic effects of narratives on smoking behavior by examining the effect of mating narratives on the discounting rates of cigarette smokers. Using data collected online, Study 1 (N = 132) assessed the within-individual effect of a mating narrative describing a long-term romantic relationship on rates of discounting after being randomly assigned to 1 of 2 narratives (romance or control) and Study 2 (N = 273) assessed the between-individual effect of 2 mating narratives (1 describing a long-term romantic relationship and 1 describing a short-term sexual encounter) on rates of discounting, craving, and cigarette valuation after being randomly assigned to 1 of 3 motivational narratives (romance, sex, or control). Reading the romance narrative decreased rates of discounting (i.e., increased preference for larger delayed rewards), compared to a control narrative (Studies 1 and 2). In contrast, reading the sexual narrative increased discounting (i.e., decreased preference for larger delayed rewards). Moreover, the romance narrative significantly decreased craving of cigarettes while the sexual narrative increased cigarette valuation (Study 2). These findings suggest that mating narratives may be useful in manipulating the temporal window of reward valuation, relevant for altering demand and craving, and may show potential as a component of future behavioral addiction interventions. Given the small effect sizes, replicating the study in future research will be beneficial. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Behavioral economic tobacco demand in relation to cigarette consumption and nicotine dependence: a meta-analysis of cross-sectional relationships

BACKGROUND AND AIMS

A cigarette purchase task (CPT) aims to characterize individual variation in the reinforcing value of tobacco. This meta-analysis estimated the associations between cigarette demand, tobacco consumption and nicotine dependence using this task.

DESIGN

A meta-analysis of cross-sectional studies identified by PubMed and PsycINFO databases was conducted. Fixed- and random-effects models were used. The study also examined the model used to derive elasticity of demand (exponential or exponentiated) as a potential moderator. Publication bias was assessed using 'fail-safe N', Begg-Mazumdar test, Egger's test, Tweedie's trim-and-fill approach and meta-regression of publication year with effect size.

SETTING

Studies from any setting that reported coefficient correlations on the tested associations.

PARTICIPANTS

Daily cigarette users (i.e. 5 to 38 cigarettes per day; n = 7649).

MEASUREMENTS

Cigarette consumption, nicotine dependence and five tobacco demand indicators: intensity (i.e. consumption at no cost), elasticity (i.e. sensitivity to rises in costs), Omax (maximum expenditure), Pmax (i.e. price at which consumption becomes elastic) and breakpoint (i.e. price at which consumption ceases).

FINDINGS

Twenty-three studies met inclusion criteria. All the CPT indices were significantly correlated with smoking behavior (rs = 0.044-0.572, Ps = 0.012-10-8 ). Medium-to-large effect size associations were present for intensity, Omax, and elasticity, whereas small effects were obtained for breakpoint and Pmax . Evidence of a moderating effect of the different elasticity modeling approaches was not present. There was limited evidence of publication bias.

CONCLUSIONS

All five demand indices derived from the cigarette purchase task by (CPT) were robustly associated with cigarette consumption and tobacco dependence. Of the demand indices, maximum expenditure, intensity and elasticity exhibited the largest magnitude associations.

Brief Assessment of Cigarette Demand (BACD): Initial development and correlational results in adults and adolescents

Developing briefer behavioral economic measures is an important priority to ensure that these measures can be used in a variety of different contexts and to reduce participant burden. We developed and sought to validate a Brief Assessment of Cigarette Demand (BACD). A 17-item Cigarette Purchase Task (CPT) and a 3-item BACD were completed concurrently in 2 community samples of smokers (Study 1, adult smokers [n = 80] with substance use disorders; Study 2, adolescent smokers [n = 81]). Responses on the CPT and BACD were compared on the following demand indices: (a) intensity (the number of cigarettes requested at no cost), (b) Omax (the maximum expenditure on cigarettes in a 24-hr period), and (c) breakpoint (the point at which consumption is totally suppressed/no cigarettes are purchased). Correlations of demand indices with cigarettes per day and nicotine dependence were calculated. Measures of cigarette demand on the CPT and BACD were significantly correlated, albeit at very different magnitudes, for all 3 indices in the adult sample (intensity, r = .86; breakpoint, r = .23; and Omax, r = .43) and for 2 of the indices in the adolescent sample (intensity, r = .97; breakpoint, r = .33). The CPT and BACD relationships with smoking and nicotine dependence were similar for breakpoint and intensity but not for Omax. As initial findings were mixed, additional validation work is recommended to improve psychometric properties before adoption. Valid brief measures of demand could have utility for research and treatment of addictive disorders. (PsycINFO Database Record (c) 2019 APA, all rights reserved).