“Push it!” or “Hold it!”? A comparison of nicotine-avoidance training and nicotine-inhibition training in smokers motivated to quit

Rationale Recently, experimental paradigms have been developed to strengthen automatic avoidance or inhibitory responses for smoking cues. However, these procedures have not yet been directly compared regarding their effectiveness and mechanisms of action. Objective This study compared the effects of avoidance vs. inhibitory training as an add-on to a brief smoking cessation intervention. The standard Approach-Avoidance-Task (AAT) was adapted for both training types and control conditions. Methods One hundred twenty-four smokers attended behavioral counseling for smoking cessation and were thereafter randomized to one of four training conditions: avoidance-AAT, sham-avoidance-AAT, inhibition-AAT, sham-inhibition-AAT. During a 2-week training period including five training sessions, smokers in the avoidance-AAT trained to implicitly avoid all smoking-related cues, while smokers in the inhibition-AAT trained to implicitly inhibit behavioral response to smoking cues. During sham training, no such contingencies appeared. Self-report and behavioral data were assessed before and after training. Cigarette smoking and nicotine dependence were also assessed at 4- and 12-week follow-ups. Results At posttest, avoidance training was more effective in reducing daily smoking than inhibition training. However, this difference was no longer evident in follow-up assessments. All training conditions improved other smoking- and health-related outcomes. Neither training changed smoking-related approach biases or associations, but approach biases for smoking-unrelated pictures increased and Stroop interference decreased in all conditions. Smoking devaluation was also comparable in all groups. Conclusions Avoidance training might be slightly more effective in reducing smoking than inhibitory training. Overall, however, all four training types yielded equivalent therapy and training effects. Hence, a clear preference for one type of training remains premature.

Addicted to green: priming effect of menthol cigarette packaging on brain response to smoking cues

IntroductionMentholated tobacco cigarettes are believed to be more addictive than non-menthol ones. Packaging of most menthol cigarette brands includes distinctive green hues, which may act as conditioned stimuli (ie, cues) and promote menthol smoking. To examine the cue properties of menthol cigarette packaging, we used a priming paradigm to assess the effect of packaging on the neural substrates of smoking cue reactivity. We hypothesised that menthol packaging will exert a specific priming effect potentiating smoking cue reactivity in menthol compared with non-menthol smokers.MethodsForty-two menthol and 33 non-menthol smokers underwent functional MRI while viewing smoking and neutral cues. The cues were preceded (ie, primed) by briefly presented images of menthol or non-menthol cigarette packages. Participants reported craving for cigarettes in response to each cue.ResultsMenthol packaging induced greater frontostriatal and occipital smoking cue reactivity in menthol smokers than in non-menthol smokers. Menthol packaging also enhanced the mediation by neural activity of the relationship between cue exposure and cigarette craving in menthol but not non-menthol smokers. Dynamic causal modelling showed stronger frontostriatal-occipital connectivity in response to menthol packaging in menthol compared with non-menthol smokers. The effects of non-menthol packaging did not differ between categories of smokers.ConclusionsOur findings demonstrate heightened motivational and perceptual salience of the green-hued menthol cigarette packaging that may exacerbate menthol smokers’ susceptibility to smoking cues. These effects could contribute to the greater addiction severity among menthol smokers and could be considered in the development of science-based regulation and legal review of tobacco product marketing practices.

The influence of conditioned stimuli on [11C]-(+)-PHNO PET binding in tobacco smokers after a one week abstinence

Stimuli previously paired with drugs of dependence can produce cravings that are associated with increased dopamine (DA) levels in limbic and striatal brain areas. Positron Emission Tomography (PET) imaging with [11C]-(+)-PHNO allows for a sensitive measurement of changes in DA levels. The purpose of the present study was to investigate changes in DA levels, measured with PET imaging with [11C]-(+)-PHNO, in regions of interest in smokers who had maintained abstinence for 7–10 days. Participants (N = 10) underwent two PET scans on separate days, during which they viewed either smoking-related or neutral images, in counterbalanced order. Craving was measured with the 12-item Tobacco Craving Questionnaire (TCQ) and the Questionnaire on Smoking Urges-Brief (QSU-B). Compared to neutral cues, smoking cues did not increase craving. There were no changes in [11C]-(+)-PHNO binding in the cue condition compared to the neutral condition for most regions of interest (ventral pallidum, globus pallidus, limbic striatum, associative striatum, sensorimotor striatum). However, binding potential in the substantia nigra was greater in the smoking-cue condition, indicating decreased synaptic dopamine. There is a potential change of DA level occurring in midbrain following the presentation of smoking-related cues. However, this preliminary finding would need to be validated with a larger sample.

Smokers “Context Reactivity” in Virtual Domestic Environments

<b><i>Introduction:</i></b> Although the effects of proximal smoking cues have been widely studied in smokers, little is known on the features associated with background spatial context effect, that is, “context reactivity.” The aim of this study was to investigate context reactivity exhibited by smokers in virtual cue-free domestic scenarios. <b><i>Methods:</i></b> Sixty-nine participants divided in 2 cohorts (33 smokers and 36 non-smokers) were exposed to a virtual reality session with 4 domestic room scenarios presented in a balanced order: bedroom, bathroom, kitchen, and living room. <b><i>Results:</i></b> We showed that (i) it is possible to elicit smoking craving in smokers in virtual reality, and (ii) these effects are room dependent and (iii) associated with a lower sense of presence; furthermore, (iv) smokers reported higher craving scores for alcohol and food in a room-dependent fashion compared to non-smokers. <b><i>Conclusion:</i></b> Our study provides an experimental paradigm for assessing context reactivity in smokers and suggests a potential use for the identification of non-pharmacological interventions as a co-adjuvant of smoking cessation treatment.

The influence of Conditioned Stimuli on [11C]-(+)-PHNO PET Binding in Tobacco Smokers after a One Week Abstinence

Stimuli previously paired with drugs of dependence can produce cravings that are associated with increased dopamine (DA) levels in limbic and striatal brain areas. Positron Emission Tomography (PET) imaging with [11C]-(+)-PHNO allows for a sensitive measurement of changes in DA levels. The purpose of the present study was to investigate changes in DA levels, measured with PET imaging with [11C]-(+)-PHNO, in regions of interest in smokers who had maintained abstinence for 7-10 days. Participants (N=10) underwent two PET scans on separate days, during which they viewed either smoking-related or neutral images, in counterbalanced order. Craving was measured with the 12-item Tobacco Craving Questionnaire (TCQ) and the Questionnaire on Smoking Urges-Brief (QSU-B). Compared to neutral cues, smoking cues did not increase craving. There were no changes in [11C]-(+)-PHNO binding in the cue condition compared to the neutral condition for most regions of interest (ventral pallidum, globus pallidus, limbic striatum, associative striatum, sensorimotor striatum). However, binding potential in the substantia nigra was greater in the smoking-cue condition, indicating decreased synaptic dopamine. There is a potential change of DA level occurring in midbrain following the presentation of smoking-related cues.

Environmental Tobacco Smoke Exposure and Brain Functioning Associated with Smoking Cue-Reactivity and Inhibitory Control in Nonsmoking Adolescents

<b><i>Introduction:</i></b> Despite its well-established negative effects, environmental tobacco smoke (ETS) exposure remains highly prevalent worldwide. ETS exposure is associated with a wide range of physical and mental health-related problems among youth, including an increased likelihood to develop nicotine dependence. Up till now, neurocognitive effects of ETS exposure are largely unknown, while such effects could explain the role of ETS exposure in the development of nicotine dependence. Therefore, this preregistered study investigated the role of current ETS exposure in brain functioning associated with smoking cue-reactivity and inhibitory control. <b><i>Method:</i></b> Concurrent with functional magnetic resonance imaging, nonsmoking adolescents aged 14–18 years (<i>N</i> = 51) performed a smoking cue-reactivity task, assessing brain functioning to smoking cues, and a Go/NoGo task measuring inhibitory control. ETS exposure was measured using a self-report questionnaire and biochemically verified. <b><i>Results:</i></b> No significant associations were observed between current ETS exposure and brain functioning associated with smoking cue-reactivity and inhibitory control. <b><i>Conclusion:</i></b> These findings suggest that low-to-moderate levels of current ETS exposure are not associated with increased salience of smoking cues or deficits in inhibitory control in nonsmoking adolescents. Longitudinal research is needed to further clarify the exact effect of lifetime ETS exposure on brain functioning, as well as research focusing on the effects of higher levels of ETS exposure.

Testing augmented reality for Eliciting cue-Provoked Urges to smoke: toward moving cue-exposure into the real world

Background Cue exposure for extinguishing conditioned urges to smoking cues has been promising in the laboratory, but difficult to implement in natural environments. The recent availability of augmented reality (AR) via smartphone provides an opportunity to overcome this limitation. Testing the ability of AR to elicit cue-provoked urges to smoke (i.e., cue reactivity [CR]) is the first step to systemically testing the efficacy of AR for cue exposure therapy. Objectives To test CR to smoking-related AR cues compared to neutral AR cues, and compared to in vivo cues. Methods A 2 x 2 within-subject design comparing cue content (smoking vs. neutral) and presentation modality (AR vs. in vivo) on urge response. Seventeen smokers viewed six smoking-related and six neutral cues via AR smartphone app and also six smoking and six neutral in vivo cues. Participants rated their urge to smoke and reality/co-existence of the cue. Results Average urge to smoke was higher following smoking-related AR images (Median=7.50) than neutral images (Median=3.33) (Z=−3.44; P=.001; d=1.37). Similarly, average urge ratings for in vivo smoking-related cues (Median=8.12) were higher than for neutral cues (Median=2.12) (Z=-3.44; P=.001; d=1.64). Also, greater CR was observed for in vivo cues than to AR cues (Z=-2.67, P=.008; d=.36). AR cues were generally perceived as being realistic and well-integrated. Conclusions CR was demonstrated with very large effect sizes in response to AR smoking cues, although slightly smaller than with in vivo smoking cues. This satisfies the first criterion for the potential use of AR for exposure therapy.