Influence of escalating alternative reinforcer values on cigarette choice

Enhanced decision-making in nicotine dependent individuals who abstain: A computational analysis using Hierarchical Drift Diffusion Modeling

BACKGROUND

Variability in decision-making capacity and reward responsiveness may underlie differences in the ability to abstain from smoking. Computational modeling of choice behavior, as with the Hierarchical Drift Diffusion Model (HDDM), can help dissociate reward responsiveness from underlying components of decision-making. Here we used the HDDM to identify which decision-making or reward-related parameters, extracted from data acquired in a reward processing task, contributed to the ability of people who smoke that are not seeking treatment to abstain from cigarettes during a laboratory task.

METHODS

80 adults who smoke cigarettes completed the Probabilistic Reward Task (PRT) - a signal detection task with a differential reinforcement schedule - following smoking as usual, and the Relapse Analogue Task (RAT) - a task in which participants could earn money for delaying smoking up to 50min - after a period of overnight abstinence. Two cohorts were defined by the RAT; those who waited either 0-min (n=36) or the full 50-min (n=44) before smoking.

RESULTS

PRT signal detection metrics indicated all subjects learned the task contingencies, with no differences in response bias or discriminability between the two groups. However, HDDM analyses indicated faster drift rates in 50-min vs. 0-min waiters.

CONCLUSIONS

Relative to those who did not abstain, computational modeling indicated that people who abstained from smoking for 50min showed faster evidence accumulation during reward-based decision-making. These results highlight the importance of decision-making mechanisms to smoking abstinence, and suggest that focusing on the evidence accumulation process may yield new targets for treatment.

Implementing an evidence-based prize contingency management protocol for stimulant use

INTRODUCTION

Contingency management (CM) is an efficacious treatment for stimulant use disorders. Research has developed support materials for the clinical delivery of prize-based CM and they are widely accessible, but few resources are available to support design and preparation for CM implementation. This guide aims to fill that gap.

METHOD/RESULTS

The article outlines a suggested prize CM protocol and discusses the best practices most aligned with evidence-based practices and acceptable-if-necessary modifications. The article also highlights modifications that are not evidence-based and not recommended. In addition, I discuss practical and clinical aspects of preparing for CM implementation.

CONCLUSIONS

Deviations from evidence-based practices are common, and poorly designed CM is unlikely to impact patient outcomes. This article provides planning stage guidance to support programs' adoption of evidence-based prize CM for the treatment of stimulant use disorders.

A preliminary investigation of schedule parameters on cocaine abstinence in contingency management

Contingency management (CM) interventions are the most effective psychosocial interventions for substance use disorders. However, further investigation is needed to create the most robust intervention possible. This study investigated the effects of 1) reinforcer magnitude; and 2) fixed and escalating and resetting incentives on cocaine abstinence in an outpatient trial. In this analysis, 34 treatment-seeking individuals with Cocaine Use Disorder received either high or low value incentives for providing a benzoylecgonine-negative urine sample or were in a control condition and received incentives for providing a urine sample regardless of the results. Participants received either escalating and resetting incentives, wherein the value of each incentive increased with consecutive negative samples and reset to the initial level upon a positive sample (Experiment 1), or fixed incentives, wherein they received the same value incentive for each negative urine sample they provided (Experiment 2). Large incentives produced more abstinence, although escalating and resetting reinforcer values did not have a differential effect. Large, fixed incentives promoted abstinence faster than other reinforcers, whereas smaller incentives resulted in poor abstinence and took many visits to achieve initial abstinence. Future research comparing different schedules on cocaine abstinence in a randomized control trial with a larger sample size is required.

Human Abuse Liability Assessment of Tobacco and Nicotine Products: Approaches for Meeting Current Regulatory Recommendations

Many regulatory bodies now recommend that tobacco product manufacturers provide information regarding new tobacco products' abuse liability to inform regulatory authorization of currently marketed tobacco products or new product applications (including premarket tobacco product applications in the United States). In addition, the US Food and Drug Administration (FDA) recommends including this information as part of modified risk tobacco product applications. Regulators, including FDA, and many public health officials and researchers consider abuse liability assessment a model which predicts the likelihood that the use of the tobacco product would result in addiction and be used repeatedly or even sporadically resulting in undesirable effects. Abuse liability of a new, potentially reduced harm product can also inform its ability to substitute completely for more harmful tobacco products. While many methods exist, no standard tobacco product abuse liability assessment has been established. The purpose of this review is to provide background information and practical recommendations for human abuse liability testing methods to meet tobacco regulatory needs. A combination of nicotine test product pharmacokinetic, subjective effect and/or behavioral response, and physiological response data relative to comparator products with known abuse liability satisfies some regulatory requirements. Implications: This review provides a practical inspection of the current, international regulatory recommendations for abuse liability assessment of tobacco and regulatory review of such information within the United States and also recommends study designs and methods for abuse liability testing of tobacco products based on scientific and regulatory knowledge. Given that tobacco product abuse liability testing is of increasing interest to regulatory bodies globally, especially with the emergence of novel tobacco products, this timely work provides background and functional recommendations for tobacco product abuse liability testing.

The Impact of E-liquid Propylene Glycol and Vegetable Glycerin Ratio on Ratings of Subjective Effects, Reinforcement Value, and Use in Current Smokers

INTRODUCTION

Electronic nicotine delivery systems (ENDS) vary on a wide range of characteristics that may affect reinforcement value and use. One characteristic is the ratio of two solvents commonly used in most e-liquids: propylene glycol (PG) and vegetable glycerin (VG). The goal of this study was to understand how PG/VG ratio affects subjective effects, reinforcement value, and tobacco use patterns among current smokers who try using ENDS.

AIMS AND METHODS

Current smokers with minimal ENDS use history (n = 30) sampled, in a double-blind fashion, three different e-liquids that varied in PG/VG ratio (70/30, 50/50, 0/100) while holding constant other aspects of the e-liquid and ENDS. Participants tried each e-liquid before rating the subjective effects on a modified version of the Cigarette Evaluation Questionnaire. Reinforcement value was assessed using a preference task where participants chose between the three e-liquids. The impact of each e-liquid on cigarette reinforcement was assessed using a modified version of the Cigarette Purchase Task. Participants were randomly assigned to receive one e-liquid to take home for 1 week.

RESULTS

PG/VG ratio had minimal impact on most of the tested outcomes. Participants rated the highest PG concentration as having a stronger "throat hit" than the other two. There was no significant difference between the number of participants who preferred each of the PG/VG ratios in the preference assessment. PG/VG ratio did not affect cigarette or ENDS use during the sampling week.

CONCLUSIONS

These data suggest that PG/VG ratio has minimal impact on subjective effects and reinforcement value in ENDS naive current smokers.

IMPLICATIONS

These data suggest that PG/VG ratio, within the range that is commonly used, has minimal impact on subjective effects, reinforcement value, or uptake in current smokers with minimal ENDS experience.

Behavioral Economic Research in Addiction as an Area of Growth for the Experimental Analysis of Behavior

Behavioral economics, a synthesis of the experimental analysis of behavior (EAB) and economics, seeks to determine the relative value of reinforcers as a function of various environmental constraints. Early animal and human studies often focused on drug reinforcement, and this has continued to the present. In particular, behavioral economic analyses of human and animal behavior in relation to nicotine and cigarette smoking have contributed to a greater understanding of this behavior, and to a greater reliance on these methods in the field of smoking cessation treatment, tobacco regulatory science and tobacco control. In this commentary, we briefly describe the history of behavioral economics in the context of EAB methods, the particular contribution of these methods to understanding cigarette smoking and the advance of tobacco regulation, as well as opportunities for growth and remaining challenges in this area. As behavioral economics continues to stimulate research and inform policy, we propose that the underlying elements of a rigorous analytic approach to understanding behavior are key contributors to the fruitfulness of this approach.

Longitudinal changes in smoking abstinence symptoms and alternative reinforcers predict long-term smoking cessation outcomes

BACKGROUND

Transdermal nicotine, with behavioral counseling, is among the most popular approaches used to quit smoking. Yet, 6-month cessation rates rarely exceed 20-25%. Identifying factors associated with cessation success may help researchers and clinicians develop enhanced interventions that can improve quit rates. This study examined longitudinal changes in withdrawal, craving, depression and anxiety symptoms, and alternative reinforcers, from a baseline assessment to a 6-month outcome, as predictors of 6-month smoking cessation outcomes following 8 weeks of nicotine patch treatment and counseling.

METHODS

A sample of 180 smokers, who completed an effectiveness trial that provided counseling and 8 weeks of 21mg nicotine patches, was analyzed. Generalized estimating equations evaluated changes in withdrawal and craving, depression and anxiety symptoms, and alternative reinforcers over time, between participants who were smoking at 6-months and participants who were abstinent (confirmed with carbon monoxide) at 6-months. Multiple logistic regression assessed changes in these variables as predictors of relapse.

RESULTS

Controlling for covariates associated with cessation (i.e., nicotine dependence, patch adherence, and rate of nicotine metabolism), participants who were abstinent at 6 months showed significantly lower craving and withdrawal and significantly higher substitute reinforcers from baseline to 6 months, vs. those who were smoking at 6 months (p<0.001). An increase in craving predicted relapse to smoking (p<0.05).

CONCLUSIONS

These results support continued efforts to strengthen interventions that reduce withdrawal and craving and the development of interventions to address alternative reinforcers in order to promote long-term smoking abstinence following nicotine patch treatment.

Increasing the Value of an Alternative Monetary Reinforcer Reduces Cigarette Choice in Adolescents

INTRODUCTION

Smoking can be conceptualized as an operant behavior maintained by the reinforcing effects of cigarettes. Changing the magnitude and availability of alternative reinforcers should shift behavior away from smoking. Adults' smoking behavior is sensitive to the magnitude and availability of alternative reinforcers; however, the extent to which the same is true for adolescents has not yet been shown in the laboratory.

METHODS

To test the sensitivity of adolescent smoking behavior to changes in the magnitude of alternative reinforcement, we gave adolescents who abstained overnight the opportunity to make 20 choices between receiving two puffs of their usual-brand cigarette or money. The magnitude of the monetary reinforcer was varied across sessions in counterbalanced order ($0.00, $0.10, and $0.50).

RESULTS

Results indicated that adolescents' choices for puffs decreased as a function of increasing monetary reinforcer magnitude, while money choices increased. This effect was moderated by baseline smoking level and by gender, such that heavier-smoking participants and males made more cigarette choices when the alternative monetary value was zero, and decreased their choices more steeply in response to increasing monetary value.

CONCLUSIONS

The current study validates a laboratory choice procedure for studying smoking in adolescents, and demonstrates that adolescent smoking behavior is sensitive to changes in the magnitude of concurrently available monetary reinforcers. The current paradigm can be adapted and applied to explore the effects of other variables that may affect cigarette choice in adolescents.