Sarah E. Snider

Competing neurobehavioral decision systems theory of cocaine addiction: From mechanisms to therapeutic opportunities.

Cocaine dependence is a difficult-to-treat, chronically relapsing disorder. Multiple scientific disciplines provide distinct perspectives on this disorder; however, connections between disciplines are rare. The competing neurobehavioral decision systems (CNDS) theory posits that choice results from the interaction between two decision systems (impulsive and executive) and that regulatory imbalance between systems can induce pathology, including addiction. Using this view, we integrate a diverse set of observations on cocaine dependence, including bias for immediacy, neural activity and structure, developmental time course, behavioral comorbidities, and the relationship between cocaine dependence and socioeconomic status. From the CNDS perspective, we discuss established and emerging behavioral, pharmacological, and neurological treatments and identify possible targets for future treatments. The ability of the CNDS theory to integrate diverse findings highlights its utility for understanding cocaine dependence and supports that dysregulation between the decision systems contributes to addiction.

Order in the absence of an effect: Identifying rate-dependent relationships.

The heterogeneity of group data can obscure a significant effect of an intervention due to differential baseline scores. Instead of discarding the seemingly heterogeneous response set, an orderly lawful relationship could be present. Rate dependence describes a pattern between a baseline and the change in that baseline following some intervention. To highlight the importance of analyzing data from a rate-dependent perspective, we (1) briefly review research illustrating that rate-dependent effects can be observed in response to both drug and non-drug interventions in varied schedules of reinforcement in clinical and preclinical populations; (2) observe that the process of rate-dependence likely requires multiple parts of a system operating simultaneously to evoke differential responding as a function of baseline; and (3) describe several statistical methods for consideration and posit that Oldhams correlation is the most appropriate for rate-dependent analyses. Finally, we propose future applications for these analyses in which the level of baseline behavior exhibited prior to an intervention may determine the magnitude and direction of behavior change and can lead to the identification of subpopulations that would be benefitted. In sum, rate dependence is an invaluable perspective to examine data following any intervention in order to identify previously overlooked results.

21st century neurobehavioral theories of decision making in addiction: Review and evaluation

&NA; This review critically examines neurobehavioral theoretical developments in decision making in addiction in the 21st century. We specifically compare each theory reviewed to seven benchmarks of theoretical robustness, based on their ability to address: why some commodities are addictive; developmental trends in addiction; addiction‐related anhedonia; self‐defeating patterns of behavior in addiction; why addiction co‐occurs with other unhealthy behaviors; and, finally, means for the repair of addiction. We have included only self‐contained theories or hypotheses which have been developed or extended in the 21st century to address decision making in addiction. We thus review seven distinct theories of decision making in addiction: learning theories, incentive‐sensitization theory, dopamine imbalance and systems models, opponent process theory, strength models of self‐control failure, the competing neurobehavioral decision systems theory, and the triadic systems theory of addiction. Finally, we have directly compared the performance of each of these theories based on the aforementioned benchmarks, and highlighted key points at which several theories have coalesced. HighlightsThe field of addiction science must understand the decisional processes that result in continued substance use.We have reviewed seven theories developed or extended in the 21st century to understand decision making in addiction.We have evaluated each theory on its ability to answer six key questions within the field of addiction.No one theory provides complete and independent answers to all of these six key questions.

Toward Narrative Theory: Interventions for Reinforcer Pathology in Health Behavior

Reinforcer pathology describes the interaction between excessive devaluation of delayed rewards and excessive valuation of commodities such as drugs or food. In isolation, both components of reinforcer pathology increase risk for substance-use disorders and other maladaptive health behaviors (e.g., poor diet); in combination, these components synergistically increase risk. In this chapter, we review evidence that reinforcer pathology may arise from imbalance between two competing neurobehavioral decision systems (CNDS)—the impulsive system, comprising the limbic and paralimbic brain regions, and the executive system, comprising the prefrontal and parietal cortices. To correct imbalance between these systems and restore normative decision making, we introduce narrative theory, a novel intervention framework that seeks to harness humans’ unique sensitivity to language and storytelling in order to both understand and potentially treat the maladaptive decision making observed in addiction and other maladaptive health behaviors. We provide both an overview of methods used in investigations of narrative theory and a summary of effects of these methods on both discounting of delayed rewards and valuation of commodities that may damage health, such as drugs and energy-dense food.

Reinforcer Pathology: The Behavioral Economics of Abuse Liability Testing

Understanding the abuse liability of novel drugs is critical to understanding the risk these new compounds pose to society. Behavioral economics, the integration of psychology and economics, can be used to predict abuse liability of novel substances. Here, we describe the behavioral economic concept of reinforcer pathology and how it may predict the use of novel drugs in existing drug‐users and initiation of use in the drug‐naive.

Novel Therapeutics for Addiction: Behavioral Economic and Neuroeconomic Approaches

Opinion statementBehavioral economic and neuroeconomic understandings of addiction offer both established and empirically supported treatments as well as a foundation from which promising new treatment options are emerging. Addiction must be understood and treated as a state of pathological overvaluation of the reinforcement of drug use fueled by an imbalance of the competing neurobehavioral decision systems that govern decision making (CNDS theory). The CNDS theory presents two systems, the executive and impulsive, which are dysregulated in reinforcer pathology by greater relative control of the impulsive, hedonic system, and lesser relative control of the executive, regulatory system. This leads to a reinforcer pathology where drug use is maladaptively overvalued in comparison to other reinforcers, leading to a chronic and often relapsing state of addiction. Some treatments which directly alter economic variables associated with drug use have already been empirically supported, including contingency management (which increases the short-term price of drug use) and drug agonist therapies (which decrease the short-term value of drug use compared to other reinforcers). New, promising treatments which bring the fundamental CNDS dysregulation of addiction into balance include episodic future thinking, which increases the temporal window over which the opportunity costs of drug use are integrated by engaging executive control, and TMS therapies which directly increase activity, and therefore relative control, in the executive system. The maturing fields of behavioral economics and neuroeconomics provide conceptual understanding of the competing neurobehavioral decision systems theory (CNDS) and reinforcer pathology (i.e., high valuation of and excessive preference for drug reinforcers), allowing us to coherently categorize treatments into a theoretically comprehensive framework of addiction. In this chapter, we identify and clarify how existing and novel interventions can ameliorate reinforcer pathology in light of the CNDS and be leveraged to treat addiction.

Narrative theory: II. Self-generated and experimenter-provided negative income shock narratives increase delay discounting.

Reading experimenter-provided narratives of negative income shock has been previously demonstrated to increase impulsivity, as measured by discounting of delayed rewards. We hypothesized that writing these narratives would potentiate their effects of negative income shock on decision-making more than simply reading them. In the current study, 193 cigarette-smoking individuals from Amazon Mechanical Turk were assigned to either read an experimenter-provided narrative or self-generate a narrative describing either the negative income shock of job loss or a neutral condition of job transfer. Individuals then completed a task of delay discounting and measures of affective response to narratives, as well as rating various narrative qualities such as personal relevance and vividness. Consistent with past research, narratives of negative income shock increased delay discounting compared to control narratives. No significant differences existed in delay discounting after self-generating compared to reading experimenter-provided narratives. Positive affect was lower and negative affect was higher in response to narratives of job loss, but affect measures did not differ based on whether narratives were experimenter-provided or self-generated. All narratives were rated as equally realistic, but self-generated narratives (whether negative or neutral) were rated as more vivid and relevant than experimenter-provided narratives. These results indicate that the content of negative income shock narratives, regardless of source, consistently drives short-term choices.

The Return of Rate Dependence.

Rate dependence, a well-known phenomenon in behavioral pharmacology, appears to have declined as a topic of interest, perhaps, as a result of being viewed pertinent to only the preclinical investigation of drugs on schedule-controlled performance. Obstacles to data interpretation due to conflation with regression to the mean also appear to have contributed to the topics decline. Despite this reduction in exposure, rate dependence is a useful concept and tool that can be used to determine sources of variability, predict therapeutic outcomes, and identify individuals that are most likely to respond therapeutically. Armed with new statistical methods and an understanding of the broad range of conditions under which rate dependence can be observed, we urge researchers to revisit the concept, use the appropriate analysis methods, and to design empirical studies a priori to further explore rate dependence.

Decision-Based Disorders: The Challenge of Dysfunctional Health Behavior and the Need for a Science of Behavior Change

Dysfunctional health behavior is a contemporary challenge, exemplified by the increasingly significant portion of health problems stemming from people’s own behavior and decision making. The challenge not only includes the direct consequences of unhealthy behavioral patterns but also their origins and the creation of policies that effectively decrease their frequency. A framework rooted in behavioral economics identifies the processes and mechanisms underlying poor health. Two behavioral economic processes, economic demand and delay discounting, are discussed in detail. Through continued development, this behavioral economic framework can guide improved outcomes in treatment and policies related to dysfunctional health behavior. Approaches are evolving to alter demand and discounting. Current and prospective policies aimed at decreasing unhealthy behavior may profit from such research.