Given what is known from animal extinction theory and research about extinguishing learned behavior, it is not surprising that cue-exposure treatments so often fail. This paper reviews current animal research regarding the most salient threats to the development and maintenance of extinction, and suggests several major procedures for increasing the efficacy of cue-exposure addiction treatment.

Smokers are highly reactive to smoking-related cues that are directly linked, or most proximal, to actual smoking behavior (e.g., lit cigarettes). However, over the course of smoking, proximal cues may not be the only stimuli to become strongly associated with smoking. Distal cues, such as the environments in which smoking occurs (e.g., bar) might also gain associative properties and come to evoke robust reactivity from smokers. To test this, a pilot study was first conducted to develop standard pictorial stimuli of smoking and nonsmoking environments, all of which were completely devoid of proximal smoking cues. A comparison set of smoking and nonsmoking proximal cues was then created. Using the 12 total pictorial cues developed, 62 adult smokers participated in a cuereactivity study during which they viewed and rated pictorial smoking and nonsmoking environment and proximal cues. Results demonstrate that, similar to proximal cues, environments associated with smoking can alone function as stimuli capable of evoking strong subjective reactivity from smokers. This work supports a broader conceptualization of drug-related cues in cue-based research and treatment development that includes proximal and distal cues as distinct categories. Keywordscraving; cue reactivity; proximal and distal stimuli; environments; smoking Cue-based research offers a wealth of information regarding how smokers respond to smokingrelated stimuli, or cues, associated with past cigarette use. Studies aimed at eliciting responses to such cues in smokers typically employ a paradigm in which smokers are exposed to smokingand nonsmoking-related stimuli through in vivo (e.g., watching someone smoke), imaginal (e.g., imagining smoking scenes), audio (e.g., hearing a description of smoking), and less commonly video (e.g., seeing a film of someone smoking), and/or pictorial (e.g., viewing pictures of smoking-related paraphernalia) stimulus modes. On balance this research has revealed that, regardless of presentation mode, smokers consistently show robust subjective

Two notions strongly held by many smokers are that negative mood increases smoking behavior and that this increase is due to the ability of smoking to alleviate negative affect. This study used a modified mood induction procedure to examine both the impact of smoking on induced mood, as well as the effect of induced mood on actual smoking behavior. Forty-eight smokers were randomly assigned to a smoking or a water-drinking comparison group. Each participant attended 3 sessions during which 1 of 3 mood states (positive, negative, or neutral) was induced. Contrary to expectation, smoking did not attenuate negative affect. However, negative mood induction subsequently quickened latency to smoke and increased number of puffs consumed ad lib.

Background Smoking acutely relieves negative affect (NA) due to smoking abstinence but may not relieve NA from other sources, such as stressors. Methods Dependent smokers (N=104) randomly assigned to one of three smoking conditions (nicotine or denic cigarettes, or no smoking) completed four negative mood induction procedures (one per session): 1) overnight smoking abstinence, 2) challenging computer task, 3) public speech preparation, and 4) watching negative mood slides. A fifth session involved a neutral mood control. The two smoking groups took 4 puffs on their assigned cigarette, and then smoked those same cigarettes ad libitum during continued mood induction. All subjects rated their level of NA and positive affect (PA) on several measures (Mood Form, PANAS, Stress-Arousal Checklist, and STAI-state). They also rated craving and withdrawal. Results NA relief from smoking depended on the NA source (i.e. mood induction procedure) and the affect measure. Smoking robustly relieved NA due to abstinence on all 4 measures, but only modestly relieved NA due to the other sources and typically on only some measures. Smoking’s effects on PA and withdrawal were similar to effects on NA, but relief of craving depended less on NA source. Smoking reinforcement only partly matched the pattern of NA relief. Few responses differed between the nicotine and denic smoking groups. Conclusions Acute NA relief from smoking depends on the situation and the affect measure used but may not depend on nicotine intake. These results challenge the common assumption that smoking, and nicotine in particular, broadly alleviates NA.

Animal research has shown that the environments, or contexts, in which drug use occurs can play a key role in how animals respond to drug-related cues. Less is known about the role of environmental contexts in human drug-dependence research. Traditionally, cue-based studies and treatments focus on conditioned cues most proximal to drug administration (e.g., lit cigarettes, pictorial stimuli of drug paraphernalia). However, there is reason to believe that more distal cues, such as the environments in which drugs were previously used, might similarly gain associative control over human responding. This article describes a body of systematic research aimed at identifying and studying the impact of environmental contexts on smokers' cue reactivity in the laboratory. Overall, results of this program of research demonstrate that exposure to environments associated with smoking, but completely devoid of proximal smoking cues, can function as conditioned stimuli capable of evoking strong subjective responding from abstinent smokers. Furthermore, more robust reactivity can be achieved if environmental context cues are personalized using novel techniques described in this article.

Many addiction theories assume that craving plays a central role in the acquisition and maintenance of drug dependence. For example, craving is often depicted as the subjective experience of the motivational state directly responsible for all drinking in the alcoholic. Craving has two prominent features that must be explained by any viable model of craving. First, craving tends to be highly situationally specific, readily triggered by stimuli previously associated with drug use. Secondly, craving can persist well beyond the cessation of drinking in an alcoholic. Conventional theories typically address craving's cue specificity and persistence by invoking concepts of classical conditioning. These theories fall into two classes: those that emphasize withdrawal and those that focus on the positive‐incentive properties of drugs. Both types of theories assume that craving processes are represented by the concomitant activation of craving report, drug‐seeking and drug use, and specific patterns of autonomic responses. However, research fails to find more than modest relationships across these putative manifestations of craving. The cognitive processing model, described in this paper, offers a different view of craving's form and function and proposes that drug use can operate independently of the processes controlling craving. According to this model, addictive drug use is regulated by automatic cognitive processes, while craving represents the activation of non‐automatic processes. These non‐automatic processes are activated to either aid in completing interrupted drug use or block automatic drug‐use sequences. From this perspective, craving is neither irrelevant nor central to the alcoholic's drug use, but rather serves as a cognitive marker of processes that, only in some instance, may be associated with alcohol seeking and use. The research and treatment implications of this model's assumptions regarding drug use and craving processes are discussed.

Acute responses to smoking are influenced by nicotine and by nonpharmacological factors such as nicotine dose expectancy and sensory effects of smoke inhalation. Because negative mood increases smoking reinforcement, the authors examined whether these effects may be altered by mood context. Smokers (n=200) participated in 2 sessions, negative or positive mood induction, and were randomized to 1 of 5 groups. Four groups comprised the 2x2 balanced placebo design, varying actual (0.6 mg vs. 0.05 mg yield) and expected nicotine dose (expected nicotine vs. denicotinized [denic]) of cigarettes. A fifth group was a no-smoking control. Smoking, versus not smoking, attenuated negative affect, as well as withdrawal and craving. Negative mood increased smoking reinforcement. However, neither actual nor expected nicotine dose had much influence on these responses; even those smokers receiving and expecting a denic cigarette reported attenuated negative affect. A follow-up comparison suggested that the sensory effects of smoke inhalation, but not the simple motor effects of smoking behavior, were responsible. Thus, sensory effects of smoke inhalation had a greater influence on relieving negative affect than actual or expected nicotine intake.

Pictorial representations of specific environments related to smoking can evoke robust craving to smoke, even in the absence of any proximal cues to smoke (e.g., cigarettes, lighters.) To evaluate the salience of smoking environment cues, we developed a novel procedure for bringing smokers’ real world smoking and nonsmoking environments into the laboratory to compare them with standard (i.e. not personalized) environments within a cue-reactivity paradigm. Seventy-two smokers used digital cameras to take pictures of the environments in which they do and do not smoke. They then completed a cue-reactivity session during which they viewed and rated pictures of smoking and nonsmoking environments, half personal and half standard, all devoid of proximal smoking cues. As hypothesized, personal environments led to a significantly larger smoking-nonsmoking difference in craving, compared with the standard environments. Personalization also enhanced stimuli vividness, relevance, positive affect, and excitement, as well as heart rate changes from baseline. Implications of these findings for exposure-based research and treatment for addiction, as well as other psychological disorders, are discussed.