Cocaine behavioral economics: from the naturalistic environment to the controlled laboratory setting

Environmental Uncertainty and Substance Use Disorders: A Behavior Analytic Perspective

Substance use disorder (SUD) and drug overdose deaths represent major economic, health, and safety issues in the United States. The psychology of uncertainty provides a mechanism for understanding, reducing, and controlling the damage from substance misuse. Illicit drugs (such as heroin or cocaine) are uncertain in their availability, quality, and acquisition (the time and effort required to obtain them) compared with nondrug-related alternatives (such as consumable goods, hobbies, or paychecks). Furthermore, the severity and likelihood of negative outcomes associated with drug use likewise are uncertain. Such uncertainties worsen substance use outcomes. The current review conveys what is known about the impact of uncertainty on substance use: laboratory investigations of uncertain time and effort required to obtain a substance and uncertain drug quality show uncertainty exacerbates harm. Furthermore, uncertain negative outcomes are not likely to deter substance use in individuals with a SUD. Finally, several policy implications include access to agonist medications; creating a safer drug supply; access to clean syringes/needles, naloxone, and safe-injection sites; and ending incarceration for substance use.

Choice between food and cocaine reinforcers under fixed and variable schedules in female and male rhesus monkeys

Illicit drugs like cocaine may be uncertain in terms of the time and effort required to obtain them. Behavior maintained by variable schedules resembles excessive drug-taking compared with fixed schedules. However, no prior research has examined fixed versus variable schedules in drug versus nondrug choice. The present study evaluated cocaine versus food choice under fixed- (FR) and variable-ratio (VR) schedules. The simpler food versus food and cocaine versus cocaine arrangements also were included. Adult female (n = 6) and male (n = 7) rhesus monkeys chose between cocaine (0.01-0.18 mg/kg/injection) and food (4 pellets/delivery), food and food (4 pellets/delivery), or cocaine and cocaine (0.018-0.03 mg/kg/injection) under FR and VR 100 and 200 schedules. In cocaine versus food choice, cocaine's potency to maintain choice was greatest when available under a VR 100 or 200 schedule and food under an FR schedule and was lowest when cocaine was available under an FR 200 schedule and food was available under a VR 200 schedule. In food versus food choice, males chose food associated with a VR schedule more than food associated with an FR schedule. In cocaine versus cocaine choice, females and males chose cocaine associated with a VR schedule more than cocaine associated with an FR schedule, particularly under VR 200. These findings suggest that uncertainty in terms of time and effort required to obtain cocaine, or perhaps the occasional low-cost access that results from VR schedules, results in greater allocation of behavior toward drug reinforcers at the expense of more certain, nondrug alternatives. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Applied Quantitative Analysis of Behavior: What It Is, and Why We Care-Introduction to the Special Section

Science evolves from prior approximations of its current form. Interest in changes in species over time was not a new concept when Darwin made his famous voyage to the Galapagos Islands; concern with speciation stretches back throughout the history of modern thought. Behavioral science also does and must evolve. Such change can be difficult, but it can also yield great dividends. The focus of the current special section is on a common mutation that appears to have emerged across these areas and the critical features that define an emerging research area-applied quantitative analysis of behavior (AQAB). In this introduction to the "Special Issue on Applications of Quantitative Methods," we will outline some of the common characteristics of research in this area, an exercise that will surely be outdated as the research area continues to progress. In doing so, we also describe how AQAB is relevant to theory, behavioral pharmacology, applied behavior analysis, and health behaviors. Finally, we provide a summary for the articles that appear in this special issue. The authors of these papers are all thinking outside the Skinner box, creating new tools and approaches, and testing them against relevant data. If we can keep up this evolution of methods and ideas, behavior analysis will regain its place at the head of the table!

The Potential Impact of Legalization of Recreational Cannabis among Current Users: A Qualitative Inquiry

Given legislative initiatives in Rhode Island pertaining to consideration of cannabis legalization for recreational purpose, a qualitative inquiry was conducted regarding anticipated changes in use among recreational cannabis users in Rhode Island. Five focus groups were conducted with recreational cannabis users (N = 31; 6-7 per group). Participants were queried about anticipated impact of legalization on their use patterns. Themes were identified using applied thematic analysis. Participants discussed (1) a desire to maintain the status quo due to satisfaction with local cannabis regulations and their current use behaviors, (2) how and why cannabis use may change, including pros and cons of legalization, and (3) anticipated changes in purchasing behavior given display and legitimacy of legal dispensaries. While participants anticipate use levels and prevalence may remain relatively stable following legislation changes, findings suggest possible changes related to mode of administration and location of use. Public health concerns exist related to high-risk potencies and use of cannabis in edible form; therefore, trialing of new cannabis products has important clinical implications should legalization occur in Rhode Island.

N-acetylcysteine reduces cocaine-seeking behavior and anterior cingulate glutamate/glutamine levels among cocaine-dependent individuals

N-acetylcysteine (NAC) is a cystine prodrug shown to reduce cocaine- and cue-primed reinstatement of cocaine-seeking behavior in preclinical studies. In this inpatient study, the effects of NAC maintenance versus placebo on cocaine-seeking behavior were examined during cocaine-primed and unprimed self-administration sessions among non-treatment-seeking, cocaine-dependent individuals. Twelve participants completed this double-blind, placebo-controlled, within-subject crossover study. Each participant was maintained for 1 week (Sat-Fri) on NAC (1200-mg TID; 3600 mg/day total) and 1 week on placebo (0-mg TID); medication order was randomized. A subset of participants underwent proton magnetic resonance spectroscopy scans (n = 8) on the third day of medication (Mon) to assess neurochemistry in the rostral anterior cingulate (rACC; voxel = 4.5 cm³ ). In four randomized sessions (Tue-Fri) each week, each participant could earn unit amounts of cocaine (10 mg, fixed) versus money ($0.50 vs. $1.50) on a choice, progressive ratio schedule after insufflating active versus placebo cocaine-priming doses (110 mg vs. 4 mg). Relative to the placebo priming dose, the active cocaine priming dose (110 mg) increased cocaine-seeking behavior (p = .003). NAC reduced cocaine-primed cocaine-seeking behavior compared with placebo levels (p = .044) but did not alter placebo-primed cocaine-seeking behavior. The larger money alternative ($1.50) suppressed cocaine-seeking behavior relative to the smaller money alternative ($0.50; p = .011). Compared with placebo levels, NAC significantly decreased rACC glutamate + glutamine levels (p = .035) and numerically decreased rACC glutamate levels (p = .085). These preliminary findings indicate that NAC suppresses cocaine-seeking behavior in some, but not all, experimental scenarios. Further, our findings suggest NAC may exert its therapeutic effects by modulating excitatory tone in the rACC.

Demand curve analysis of marijuana use among persons living with HIV

BACKGROUND

Despite medicalization and legalization of marijuana use, factors influencing demand for marijuana among persons living with HIV (PLWH) are incompletely understood. This knowledge gap undermines effective clinical management and policies. This study used demand curve simulation methods to address these issues.

METHODS

Marijuana-using PLWH (N = 119) completed experimental tasks to simulate amount of marijuana purchasing/use across different costs (money or time), and likelihood of reselling marijuana or marijuana therapeutic-use registration card in relation to profits. Additional simulations assessed purchasing of marijuana relative to other drug and non-drug goods.

RESULTS

Simulated marijuana use decreased as money and time costs increased. Consumption was greater for participants with more severe Cannabis Use Disorder (CUD) and anxiety, intermediate pain levels, and past 90-day opioid use. Whereas few participants chose to sell their registration card, marijuana resale (diversion) steeply increased with profit. Likelihood of seeking marijuana therapeutic-use certification decreased in relation to registration card money cost, having to visit more physicians to get a signature, and delay to receiving the card, and increased with duration of certification. Participants who reported recent opioid use were more likely to seek certification. Consumption of several commodities assessed was independent of marijuana.

CONCLUSIONS

Simulated marijuana use was related to participants' clinical profile (CUD, anxiety and pain symptoms, recent opioid use), and unrelated to purchasing other goods. Likelihood of seeking marijuana therapeutic-use registration was affected by several types of costs and recent opioid use. Participants were unlikely to divert registration cards. We discuss clinical and policy implications of these findings.

Unpredictability as a modulator of drug self-administration: Relevance for substance-use disorders

Drug self-administration has been regarded as a gold-standard preclinical model of addiction and substance-use disorder (SUD). However, investigators are becoming increasingly aware, that certain aspects of addiction or SUDs experienced by humans are not accurately captured in our preclinical self-administration models. The current review will focus on two such aspects of current preclinical drug self-administration models: 1) Predictable vs. unpredictable drug access in terms of the time and effort put into obtaining drugs (i.e., response requirement) and drug quality (i.e., amount) and 2) rich vs. lean access to drugs. Some behavioral and neurobiological mechanisms that could contribute to excessive allocation of behavior toward drug-seeking and drug-taking at the expense of engaging in nondrug-related activities are discussed, and some directions for future research are identified. Based on the experiments reviewed, lean and unpredictable drug access could worsen drug-seeking and drug-taking behavior in individuals with SUDs. Once more fully explored, this area of research will help determine whether and how unpredictable and lean cost requirements affect drug self-administration in preclinical laboratory studies with nonhuman subjects and will help determine whether incorporating these conditions in current self-administration models will increase their predictive validity.

Prediction of attempted suicide in men and women with crack-cocaine use disorder in Brazil

Background

Suicide is a severe health problem, with high rates in individuals with addiction. Considering the lack of studies exploring suicide predictors in this population, we aimed to investigate factors associated with attempted suicide in inpatients diagnosed with cocaine use disorder using two analytical approaches.

Methods

This is a cross-sectional study using a secondary database with 247 men and 442 women hospitalized for cocaine use disorder. Clinical assessment included the Addiction Severity Index, the Childhood Trauma Questionnaire, and the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, totalling 58 variables. Descriptive Poisson regression and predictive Random Forest algorithm were used complementarily to estimate prevalence ratios and to build prediction models, respectively. All analyses were stratified by gender.

Results

The prevalence of attempted suicide was 34% for men and 50% for women. In both genders, depression (PR_M = 1.56, PR_W = 1.27) and hallucinations (PR_M = 1.80, PR_W = 1.39) were factors associated with attempted suicide. Other specific factors were found for men and women, such as childhood trauma, aggression, and drug use severity. The men's predictive model had prediction statistics of AUC = 0.68, Acc. = 0.66, Sens. = 0.82, Spec. = 0.50, PPV = 0.47 and NPV = 0.84. This model identified several variables as important predictors, mainly related to drug use severity. The women's model had higher predictive power (AUC = 0.73 and all other statistics were equal to 0.71) and was parsimonious.

Conclusions

Our findings indicate that attempted suicide is associated with depression, hallucinations and childhood trauma in both genders. Also, it suggests that severity of drug use may be a moderator between predictors and suicide among men, while psychiatric issues shown to be more important for women.

Further validation of a marijuana purchase task

BACKGROUND

A valid measure of the relative economic value of marijuana is needed to characterize individual variation in the drug's reinforcing value and inform evolving national marijuana policy. Relative drug value (demand) can be measured via purchase tasks, and demand for alcohol and cigarettes has been associated with craving, dependence, and treatment response. This study examined marijuana demand with a marijuana purchase task (MPT).

METHODS

The 22-item self-report MPT was administered to 99 frequent marijuana users (37.4% female, 71.5% marijuana use days, 15.2% cannabis dependent).

RESULTS

Pearson correlations indicated a negative relationship between intensity (free consumption) and age of initiation of regular use (r=-0.34, p<0.001), and positive associations with use days (r=0.26, p<0.05) and subjective craving (r=0.43, p<0.001). Omax (maximum expenditure) was positively associated with use days (r=0.29, p<0.01) and subjective craving (r=0.27, p<0.01). Income was not associated with demand. An exponential demand model provided an excellent fit to the data across users (R(2)=0.99). Group comparisons based on presence or absence of DSM-IV cannabis dependence symptoms revealed that users with any dependence symptoms showed significantly higher intensity of demand and more inelastic demand, reflecting greater insensitivity to price increases.

CONCLUSIONS

These results provide support for construct validity of the MPT, indicating its sensitivity to marijuana demand as a function of increasing cost, and its ability to differentiate between users with and without dependence symptoms. The MPT may denote abuse liability and is a valuable addition to the behavioral economic literature. Potential applications to marijuana pricing and tax policy are discussed.

Use of Preclinical Drug vs. Food Choice Procedures to Evaluate Candidate Medications for Cocaine Addiction

Drug addiction is a disease that manifests as an inappropriate allocation of behavior towards the procurement and use of the abused substance and away from other behaviors that produce more adaptive reinforcers (e.g. exercise, work, family and social relationships). The goal of treating drug addiction is not only to decrease drug-maintained behaviors, but also to promote a reallocation of behavior towards alternative, nondrug reinforcers. Experimental procedures that offer concurrent access to both a drug reinforcer and an alternative, nondrug reinforcer provide a research tool for assessment of medication effects on drug choice and behavioral allocation. Choice procedures are currently the standard in human laboratory research on medications development. Preclinical choice procedures have been utilized in biomedical research since the early 1940's, and during the last 10-15 years, their use for evaluation of medications to treat drug addiction has increased. We propose here that parallel use of choice procedures in preclinical and clinical studies will facilitate translational research on development of medications to treat cocaine addiction. In support of this proposition, a review of the literature suggests strong concordance between preclinical effectiveness of candidate medications to modify cocaine choice in nonhuman primates and rodents and clinical effectiveness of these medications to modify either cocaine choice in human laboratory studies or metrics of cocaine abuse in patients with cocaine use disorder. The strongest evidence for medication effectiveness in preclinical choice studies has been obtained with maintenance on the monoamine releaser d-amphetamine, a candidate agonist medication for cocaine use analogous to use of methadone to treat heroin abuse or nicotine formulations to treat tobacco dependence.

Using behavioral economics to predict opioid use during prescription opioid dependence treatment

BACKGROUND

Research grounded in behavioral economics has previously linked addictive behavior to disrupted decision-making and reward-processing, but these principles have not been examined in prescription opioid addiction, which is currently a major public health problem. This study examined whether pre-treatment drug reinforcement value predicted opioid use during outpatient treatment of prescription opioid addiction.

METHODS

Secondary analyses examined participants with prescription opioid dependence who received 12 weeks of buprenorphine-naloxone and counseling in a multi-site clinical trial (N=353). Baseline measures assessed opioid source and indices of drug reinforcement value, including the total amount and proportion of income spent on drugs. Weekly urine drug screens measured opioid use.

RESULTS

Obtaining opioids from doctors was associated with lower pre-treatment drug spending, while obtaining opioids from dealers/patients was associated with greater spending. Controlling for demographics, opioid use history, and opioid source frequency, patients who spent a greater total amount (OR=1.30, p<.001) and a greater proportion of their income on drugs (OR=1.31, p<.001) were more likely to use opioids during treatment.

CONCLUSIONS

Individual differences in drug reinforcement value, as indicated by pre-treatment allocation of economic resources to drugs, reflects propensity for continued opioid use during treatment among individuals with prescription opioid addiction. Future studies should examine disrupted decision-making and reward-processing in prescription opioid users more directly and test whether reinforcer pathology can be remediated in this population.