Reactivity In Smokers Research Articles

Smokers “Context Reactivity” in Virtual Domestic Environments

Introduction: 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. Methods: 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. Results: 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. Conclusion: 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.

Examining sex, adverse childhood experiences, and oxytocin on neuroendocrine reactivity in smokers

Adverse childhood experiences (ACE) are associated with greater neuroendocrine responses to social stress in substance users. The neuropeptide oxytocin might attenuate this relationship. Given sex differences in ACE exposure and neuroendocrine stress reactivity, it is unknown whether this association is similar for males and females. Therefore, this secondary analysis evaluated the interactive effect of sex, ACE, and acute oxytocin administration on neuroendocrine stress responses in adult cigarette smokers (N = 144). Participants completed the Adverse Childhood Experiences Questionnaire at screening and were randomized to receive intranasal oxytocin or placebo before undergoing the Trier Social Stress Task (TSST). Cortisol levels were assessed at pre- and post-medication administration and at 20 and 40 min following the TSST. Generalized linear mixed models were developed to predict post-TSST cortisol levels. Predictors included treatment assignment (placebo vs. oxytocin), sex (male vs. female), ACE (0–10 total score), pre-medication cortisol levels, and minutes since medication administration. The hypothesized three-way interaction between sex, oxytocin, and ACE scores was significant. Linear associations between ACE scores and cortisol reactivity indicated higher ACE scores were associated with attenuated cortisol response in females, regardless of treatment condition. For males, higher ACE scores were associated with heightened cortisol response, an effect that was attenuated by oxytocin. Results indicate that the association between ACE and neuroendocrine reactivity to social stress, as well as the attenuating effect of oxytocin, is differentially impacted by sex. Males with greater childhood adversity may be more likely to benefit from oxytocin’s anxiolytic properties.

Neural substrates of smoking and reward cue reactivity in smokers: a meta-analysis of fMRI studies

Smoking is partly attributed to alterations of reward processing. However, findings on the neurobiological mechanisms that underlie smoking-related and smoking-unrelated reward processing in smokers have been inconsistent. Neuroimaging experiments that used functional magnetic resonance imaging (fMRI) and reported brain responses to smoking-related cues and nonsmoking reward-related cues in smokers and healthy controls as coordinates in a standard anatomic reference space were identified by searching the PubMed, Embase, and Web of Science databases up to December 2018. Three meta-analyses were performed using random-effect nonparametric statistics with Seed-based d Mapping software, with brain activity contrast from individual studies as the input. The striatum showed higher activation in response to smoking-related cues compared with neutral cues in 816 smokers from 28 studies and lower activation in response to nonsmoking reward-related cues in 275 smokers compared with 271 healthy control individuals from 13 studies. The relative reactivity of the putamen to smoking-related cues increased in 108 smokers compared with 107 healthy controls from seven studies. Meta-regression showed that smokers with a greater severity of nicotine dependence exhibited less engagement of the striatum in response to both smoking-related cues and nonsmoking reward-related cues. The present results reveal the disruption of reward system function in smokers and provide new insights into diverging theories of addiction. With the escalation of nicotine dependence, nicotine appears to exert dynamic effects on reward processing, based on incentive sensitization theory and reward deficiency syndrome theory.

The dopamine D2 receptor mediates approach-avoidance tendencies in smokers.

Dopamine D2 receptors (DRD2) have been strongly implicated in reward processing of natural stimuli and drugs. Using the approach-avoidance task (AAT), we recently demonstrated that smokers show an increased approach-bias toward smoking-related cues but not toward naturally rewarding stimuli. Here, we examined the contribution of the DRD2 Taq1B polymorphism to smokers' and non-smokers' responsivity toward smoking versus naturally rewarding stimuli in the AAT. Smokers carrying the minor B1 allele of the DRD2 Taq1B polymorphism showed reduced approach behavior for food-related pictures compared to non-smokers with the same allele. In the group of smokers, a higher approach-bias toward smoking-related compared to food-related pictures was found in carriers of the B1 allele. This pattern was not evident in smokers homozygous for the B2 allele. In addition, smokers with the B1 allele reported fewer attempts to quit smoking relative to smokers homozygous for the B2 allele. This is the first study demonstrating that behavioral shifts in response to smoking relative to natural rewards in smokers are mediated by the DRD2 Taq1B polymorphism. Our results indicate a reduced natural-reward brain reactivity in smokers with a genetically determined decrease in dopaminergic activity (i.e., reduction of DRD2 availability). It remains to be determined whether this pattern might be related to a different outcome after psychological cessation interventions, i.e., AAT modification paradigms, in smokers.

Cue reactivity in smokers: An event-related potential study

Drugs-of-abuse may increase the salience of drug cues by sensitizing the dopaminergic (DA) system (Robinson and Berridge, 1993), leading to differential attention to smoking stimuli. Event-related potentials (ERPs) have been used to assess attention to smoking cues but not using an ERP component associated with DA-mediated salience evaluation. In this study the DA-related P2a and the P3, were compared in smokers (N=21) and non-smokers (N=21) during an attention selection cue exposure task including both cigarette and neutral images. We predicted that both the P2a and P3 would be larger to targets than non-targets, but larger to non-target cigarette images than non-target neutral images only in the smokers, reflecting smokers' evaluation of smoking stimuli as relevant even when they were not targets. Results indicated that smokers showed behavioral cue reactivity, with more false alarms to cigarette images (responding to cigarette images when they were not targets) than non-smokers; however, both smokers and non-smokers had a larger P2a and P3 to cigarette images. Thus, while smokers showed behavioral evidence of differential salience evaluation of the cigarette images, this group difference was not reflected in differential brain activity. These findings may reflect characteristics of the ERPs (both ERP components were smaller in the smokers), the smoking sample (they were not more impulsive, i.e. reward sensitive, than the non-smokers, in contrast to prior studies) and the design (all participants were aware that the aim of the study was related to smoking).

Smoking a virtual cigarette increases craving among smokers

Previous studies have shown the efficacy of virtual reality (VR) environments that reproduce smoking-related stimuli for increasing self-reported craving and psychophysiological reactivity in smokers. However, no study to date has attempted to simulate smoking behavior itself by means of VR technology. The aim of this study was to assess the effect of smoking a virtual cigarette on self-reported craving levels and heart rate (HR) in a sample of smokers. Participants were 45 smokers randomly assigned to three VR conditions built into a virtual pub: smoking a virtual cigarette, throwing virtual darts at a virtual dartboard or just being in the virtual pub. Results showed that smoking a virtual cigarette significantly increased self-reported craving and HR when compared to the other two conditions. These results reveal that simulation of smoking behavior in a VR environment functions as an efficacious proximal cue that can be used for triggering craving under the cue-exposure paradigm.

Individual differences in smoking-related cue reactivity in smokers: An eye-tracking and fMRI study

Measures of cue reactivity provide a means of studying and understanding addictive behavior. We wanted to examine the relationship between different cue reactivity measures, such as attentional bias and subjective craving, and functional brain responses toward smoking-related cues in smokers. We used eye-tracking measurements, a questionnaire for smoking urges-brief and functional magnetic resonance imaging to assess the responses to smoking-related and neutral visual cues from 25 male smokers after 36 h of smoking abstinence. Regression analyses were conducted to determine the correlation between cue-evoked brain responses and the attentional bias to smoking-related cues. The eye gaze dwell time percentage was longer in response to smoking-related cues than neutral cues, indicating significant differences in attentional bias towards smoking-related cues. The attentional bias to smoking-related cues correlated with subjective craving ratings (r=0.660, p<0.001). The dorsolateral prefrontal cortex, the putamen, the posterior cingulate cortex and the primary motor cortex were associated with the attentional bias to smoking-related cues, whereas the orbitofrontal cortex, the insula and the superior temporal gyrus were associated with smoking-related cue-induced craving and smoking urges. These results suggest that attentional mechanisms in combination with motivational and reward-related mechanisms play a role in smoking-related cue reactivity. We confirmed a positive correlation between different smoking-related cue reactivities, such as attentional bias and subjective craving, and functional brain responses in various individuals. Further studies in this field might contribute to a better individualized understanding of addictive behavior.

Modulation of the outcome-related negativity associated with nicotine abstinence.

Cue-reactivity studies have shown that when consumers are exposed to a substance-related stimulus, potential tobacco use contributes significantly to craving and motivational drive. Although the motivational response to cues signaling tobacco availability has been widely studied, less is known about physiological reactivity to perceived cigarette availability. The aim of the present study was to examine the outcome-related negativity (ORN) evoked by stimuli that signal potential tobacco use in abstinent and sated smokers. The ORN is an event-related potential (ERP) component that reflects the emotional and motivational aspects of reward processing and is modulated by motivational value of reward. Thirty-two such smokers performed two distinct and comparable versions of a gambling task, under conditions of abstinence and satiation. The analysis of variance (ANOVA) analysis revealed that ORN amplitude was larger in abstinent than satisfied smokers on those trials in which tobacco could be used. Differences were significant at the Fz electrode (p < .01) and approached significance at the Cz (p = .061) and Pz (p = .059) electrodes. Moreover, ORN amplitude predicted subjective indices of desire and positive effects from smoking, but only in the abstinence condition. These findings suggest that perceived cigarette availability might influence physiological reactivity in smokers who are nicotine deprived. They also suggest that the ORN component may be related to the motivational mechanisms involved in addictive behavior.

Personalized smoking environment cue reactivity in smokers with schizophrenia and controls: A pilot study

Exposure to smoking cues increases craving to smoke and negatively changes mood in smokers with schizophrenia (SWS). This pilot study compared reactivity to real-world smoking environments versus neutral environments in SWS ( n = 10) and non-psychiatric control smokers (CON; n = 10). Results indicate that both SWS and CON experienced increases in smoking urges when viewing images of their smoking environments and that SWS tended to report greater increases in withdrawal-related negative mood than CON when viewing images of their smoking environments. These findings signify that personalized smoking environments trigger smoking urges in SWS and suggest that extinguishing this reactivity may aid cessation efforts in this population.

The impact of cigarette deprivation and cigarette availability on cue–reactivity in smokers

This experiment was conducted to determine the impact of cigarette deprivation and cigarette availability on reactivity measures to cigarette cues. Smokers were recruited who were 18 years of age or older, not attempting to quit or cut down on their smoking, smoked at least 20 cigarettes daily, had been smoking regularly for past year and had an expired carbon monoxide level of at least 10 parts per million. Smokers were assigned randomly to abstain from smoking for 24 hours (n = 51) or continue smoking their regular amount (n = 50). Twenty-four hours later, they were exposed to trials of either a lit cigarette or a glass of water with a 0, 50 or 100% probability of being able to sample the cue on each trial. Craving, mood, heart rate, skin conductance, puff topography and latency to access door to sample the cue were measured. Both exposure to cigarette cues and increasing availability of those cues produced higher levels of craving to smoke. Deprivation produced a generalized increase in craving. There was no consistent evidence, however, that even under conditions of high cigarette availability, deprived smokers were sensitized selectively to presentations of cigarette cues. The data suggest that, even under conditions of immediate cigarette availability, deprivation and cue presentations have independent, additive effects on self-reported craving levels in smokers.

Craving-Induced EEG Reactivity in Smokers: Effects of Mood Induction, Nicotine Dependence and Gender

Background/Aims: Cigarette craving is a core symptom of smoking withdrawal, which is more intense and more frequently observed in smokers with depressed mood. Using self-reports and electroencephalographic (EEG) indices of frontal hemispheric asymmetry, which has been shown to be sensitive to mood states, the purpose of this study was to investigate the neural basis of cue-elicited cigarette craving, its variation with experimentally induced depressed mood, and with differences in gender and smoker type. Methods: Cigarette-cue reactivity was examined in 11 (5 male) regular and 11 (6 male) light smokers in two sessions involving the induction of neutral or depressed mood. Results: Frontal EEG alpha asymmetry changes reflecting left frontal hypoactivation were evident with cigarette-cue exposure, particularly in female smokers. During cigarette-cue exposure, EEG evidenced both decreases and increases in brain state activation, with the latter activational increments also being influenced by depressed mood. Exposure to the cigarette cue, in addition to increasing withdrawal symptoms, increased cravings and negative affect, these latter effects being more evident in female and regular smokers. Conclusion: These findings, which appear to provide a physiological basis for ‘withdrawal-like’ negative affective experiences during craving, are discussed in relation to theories of drug reinforcement and smoking motivation.

Airway blood flow reactivity in smokers

Cigarette smoking has been associated with impaired endothelium-dependent relaxation responses in the brachial and coronary arteries (endothelial dysfunction). The aim of the present study was to determine if the airway circulation is also affected and if airway treatment has an effect on endothelial function. Airway blood flow ( Q aw) responses to inhaled albuterol as an index of endothelial function were measured in age-matched healthy current smokers, healthy ex-smokers, ex-smokers with COPD and healthy lifetime non-smokers; in the ex-smokers with COPD, the albuterol responsiveness was repeated after a 4-week treatment with an inhaled glucocorticoid/ β 2-adrenergic agonist combination drug. Mean baseline Q aw was similar in the four groups. Albuterol inhalation increased mean Q aw in lifetime non-smokers (50.1±8.3%; p < 0.0 5 ) and in healthy ex-smokers (37.2±3.4%; p < 0.0 5 ) but not in healthy current smokers (13.9±3.2%; p=NS) and ex-smokers with COPD (9.7±4.5%; p=NS). While drug treatment per se did not change Q aw significantly, it restored albuterol responsiveness (+67.6±11.1%; p < 0.0 5 ) in the ex-smokers with COPD. Thus, cigarette smoking is associated with endothelial dysfunction in the airway, with a partial recovery of endothelial function after smoking cessation in healthy ex-smokers but not in ex-smokers with COPD. In the latter, combined glucocorticoid/ β 2-adrenergic agonist treatment restores albuterol responsiveness.

Cue reactivity in smokers: the effects of perceived cigarette availability and gender

We examined the effects of perceived cigarette availability and gender on smoking cue reactivity. Smokers were exposed to smoking cues (smoking paraphernalia) and control cues whilst their subjective and physiological responses were measured. Perceived cigarette availability was manipulated on a between-subjects basis before cue exposure. Relative to control cues, smoking cues evoked increases in the level of skin conductance in all participants. Cigarette craving was also increased in the presence of smoking cues, but only in female participants. Perceived cigarette availability had no effect on these responses. Participants also showed salivary reactivity to smoking cues, with males showing a decrease in salivation, and females showing an increase, but only when cigarettes were perceived as unavailable. These results suggest that perceived cigarette availability may not influence craving and skin conductance reactivity to smoking cues in minimally dependent smokers who are not nicotine deprived. In addition, the present data suggest that there are important gender differences in craving reactivity to smoking cues.

The cue-availability paradigm: The effects of cigarette availability on cue reactivity in smokers.

The cue-availability paradigm: The effects of cigarette availability on cue reactivity in smokers.

Oral contraceptive use and hemodynamic, lipid, and fibrinogen responses to smoking and stress in women.

The effects of acute smoking and oral contraceptive (OC) use on cardiovascular, lipid, and fibrinogen stress responses were examined in 52 female smokers and nonsmokers, half of whom were using OCs. Women smoked or sham-smoked a cigarette and then performed 2 stressful tasks. Stress elicited increases in total and low-density lipoprotein cholesterol, and in triglycerides among women who smoked, and in fibrinogen among all women. Smokers who used OCs had greater blood pressure increases to smoking and to stress than did smokers who did not use OCs. OC use was also associated with enhanced total peripheral resistance stress responses among women who smoked and cardiac output stress responses among women who sham-smoked. Results suggest that OC use moderates cardiovascular reactivity in smokers but not nonsmokers, enhancing vascular responsivity to smoking combined with stress and myocardial responsivity to stress alone.

Cue reactivity in smokers: The role of cue characteristics.

Cue reactivity in smokers: The role of cue characteristics.