Smoking Cues Research Articles

Trait Persistence Moderates the Association between Gender and Change in Smoking Urge Across Repeated Cue Exposure Trials

Previous research suggests that persistence, an individual difference characteristic representing the ability and willingness to maintain engagement in challenging or aversive contexts, may relate to smoking relapse. Improving understanding of the persistence-relapse risk association could guide improvements in behavioural interventions. We explored whether persistence and gender related to change in smoking urges across multiple cue exposure trials (an analogue of extinction learning and relapse risk). Participants included abstinent smokers who completed 12 massed, 5-minute smoking cue exposure trials using guided imagery as well as olfactory, tactile, visual and motor cues associated with smoking. We used multilevel logistic growth curve modelling to explore predictor associations with change in urge. Results suggested that gender related to urge whereby males showed greater initial and sustained reactivity than females. Persistence was not associated with female urge trajectories. However, compared to males with high persistence, males with low persistence evidenced sustained urge reactivity over time. Results suggest that greater persistence relates to reduction of conditioned responding (e.g., urges) among abstinent male smokers when exposure trials include complex cues most closely related to nicotine self-administration. Because persistence is modifiable, males with low persistence may benefit from interventions that include elements designed to increase persistence in urge eliciting situations.

Cue-Induced Brain Activation in Chronic Ketamine-Dependent Subjects, Cigarette Smokers, and Healthy Controls: A Task Functional Magnetic Resonance Imaging Study.

Observations of drug-related cues may induce craving in drug-dependent patients, prompting compulsive drug-seeking behavior. Sexual dysfunction is common in drug users. The aim of the study was to examine regional brain activation to drug (ketamine, cigarette smoking) associated cues and natural (sexual) rewards. A sample of 129 [40 ketamine use smokers (KUS), 45 non-ketamine use smokers (NKUS) and 44 non-ketamine use non-smoking healthy controls (HC)] participants underwent functional magnetic resonance imaging (fMRI) while viewing ketamine use related, smoking and sexual films. We found that KUS showed significant increased activation in anterior cingulate cortex and precuneus in response to ketamine cues. Ketamine users (KUS) showed lower activation in cerebellum and middle temporal cortex compared with non-ketamine users (NKUS and HC) in response to sexual cues. Smokers (KUS and NKUS) showed higher activation in the right precentral frontal cortex in response to smoking cues. Non-ketamine users (NKUS and HC) showed significantly increased activation of cerebellum and middle temporal cortex while viewing sexual cues. These findings clearly show the engagement of distinct neural circuitry for drug-related stimuli in chronic ketamine users. While smokers (both KUS and NKUS) showed overlapping differences in activation for smoking cues, the former group showed a specific neural response to relevant (i.e., ketamine-related) cues. In particular, the heightened response in anterior cingulate cortex may have important implications for how attentionally salient such cues are in this group. Ketamine users (KUS) showed lower activation in response to sexual cues may partly reflect the neural basis of sexual dysfunction.

Early onset cigarette smokers exhibit greater P300 reactivity to smoking-related stimuli and report greater craving

Adolescence is a period during which a number of critical neuromaturation processes occur and the vulnerability for developing nicotine dependence is extremely high. Thus, early-onset (EO; age < 16 years old), relative to late-onset (LO; age ≥ 16 years old), tobacco smoking may be uniquely deleterious for developmentally immature systems that regulate neural signaling reactivity. This study investigated how age of tobacco smoking onset affects neurophysiological measures of smoking cue reactivity and reported craving in adult smokers. EO smokers (EOS; n = 8; 4 females), LO smokers (LOS; n = 10; 5 females), and healthy non-smokers (HNS; n = 10; 5 females) participated in an event-related potential (ERP) cue reactivity study with tactile and image stimuli. Participants handled neutral objects during one interval and smoking-related objects during a second interval. After each interval, they viewed smoking-related, neutral, or arousing images using an oddball paradigm. P300 ERPs and craving for tobacco were recorded during each session. P300 amplitudes were significantly higher in central midline (Cz) channel to smoking, but not neutral or arousing, images after handling smoking objects. Specifically, Cz P300 smoking amplitudes were significantly greater in EOS, relative to LOS and HNS, and associated with greater craving at baseline. There were no other group differences in mood or craving. EOS exhibited greater P300 reactivity to smoking-related stimuli, relative to LOS, suggesting a more sensitized neural response. EO smoking during early neuromaturation may alter neurophysiological signaling involved in responding to smoking-related stimuli, which could impact the outcome of smoking cessation interventions.

The social networks of smokers attempting to quit: An empirically derived and validated classification.

Social relationships play an important role in the uptake, maintenance, and cessation of smoking behavior. However, little is known about the natural co-occurrence of social network features in adult smokers' networks and how multidimensional features of the network may connect to abstinence outcomes. The current investigation examined whether qualitatively distinct subgroups defined by multiple characteristics of the social network could be empirically identified within a sample of smokers initiating a quit attempt. Egocentric social network data were collected from 1571 smokers (58% female, 83% white) engaged in a 3-year smoking cessation clinical trial. Using nine indicator variables reflecting both risk and protective network features, finite mixture models identified five social network subgroups: High Stress/High Contact, Large and Supportive, Socially Disconnected, Risky Friends and Low Contact, and High Contact with Smokers and Light Drinkers. External variables supported the validity of the identified subgroups and the subgroups were meaningfully associated with baseline demographic, psychiatric, and tobacco measures. The Socially Disconnected subgroup was characterized by little social interaction, low levels of stress, and low exposure to social environmental smoking cues, and had the highest probability of successful cessation at 1 week compared with all other social network subgroups. At 6 months posttreatment its members had higher abstinence rates than members of the High Stress/High Contact subgroup and the Risky Friends and Low Contact subgroup. The present study highlights the heterogeneity of smokers' social milieus and suggests that network features, especially those entailing exposure to smoking cues and contexts, heighten risk for smoking cessation failure. (PsycINFO Database Record

Combined Smoking Cues Enhance Reactivity and Predict Immediate Subsequent Smoking.

Cue reactivity (CR) research has reliably demonstrated robust cue-induced responding among smokers exposed to common proximal smoking cues (eg, cigarettes, lighter). More recent work demonstrates that distal stimuli, most notably the actual environments in which smoking previously occurred, can also gain associative control over craving. In the real world, proximal cues always occur within an environment; thus, a more informative test of how cues affect smokers might be to present these two cue types simultaneously. Using a combined-cue counterbalanced CR paradigm, the present study tested the impact of proximal (smoking and neutral) + personal environment (smoking and nonsmoking places) pictorial cues, on smokers' subjective and behavioral CR; as well as the extent to which cue-induced craving predicts immediate subsequent smoking in a within-subjects design. As anticipated, the dual smoking cue combination (ProxS + EnvS) led to the greatest cue-induced craving relative to the other three cue combinations (ProxS + EnvN, ProxN + EnvS, and ProxN ± EnvN), ps < .004. Dual smoking cues also led to significantly shorter post-trial latencies to smoke, ps < .01. Overall CR difference score (post-trial craving minus baseline craving) was predictive of subsequent immediate smoking indexed by: post-trial latency to smoke [B = -2.69, SE = 9.02; t(143) = -2.98, p = .003]; total puff volume [B = 2.99, SE = 1.13; t(143) = 2.65, p = .009]; and total number of puffs [B = .053, SE = .027; t(143) = 1.95, p = .05]. The implications of these findings for better understanding the impact of cues on smoking behavior and cessation are discussed. This novel cue reactivity study examined smokers' reactivity to combined proximal and distal smoking cues. Exposure to a combination of two smoking cues (proximal and environment) led to the greatest increases in cue-induced craving and smoking behavior compared to all other cue combinations. Further, the overall magnitude of cue-induced craving was found to significantly predict immediate subsequent smoking. This work provides new insight on how exposure to various cues and cue combinations directly affect smokers' craving and actual smoking behavior, as well as the relationship between those two indices of reactivity.

Selective attention to smoking cues in former smokers

Repeated drug use modifies the emotional and cognitive processing of drug-associated cues. These changes are supposed to persist even after prolonged abstinence. Several studies demonstrated that smoking cues selectively attract the attention of smokers, but empirical evidence for such an attentional bias among successful quitters is inconclusive. Here, we investigated whether attentional biases persist after smoking cessation. Thirty-eight former smokers, 34 current smokers, and 29 non-smokers participated in a single experimental session. We used three measures of attentional bias for smoking stimuli: A visual probe task with short (500ms) and long (2000ms) picture stimulus durations, and a modified Stroop task with smoking-related and neutral words. Former smokers and current smokers, as compared to non-smokers, showed an attentional bias in visual orienting to smoking pictures in the 500ms condition of the visual probe task. The Stroop interference index of smoking words was negatively related to nicotine dependence in current smokers. Former smokers and mildly dependent smokers, as compared to non-smokers, showed increased interference by smoking words in the Stroop task. Neither current nor former smokers showed an attentional bias in maintained attention (2000ms visual probe task). In conclusion, even after prolonged abstinence smoking cues retain incentive salience in former smokers, who differed from non-smokers on two attentional bias indices. Attentional biases in former smokers operate mainly in early involuntary rather than in controlled processing, and may represent a vulnerability factor for relapse. Therefore, smoking cessation programs should strengthen self-control abilities to prevent relapses.

Anterior insula activation during inhibition to smoking cues is associated with ability to maintain tobacco abstinence

Relapse to smoking after initial abstinence is a major clinical challenge with significant public health consequences. At the brain and behavioral level, those who relapse to tobacco smoking have both greater cue-reactivity and lower inhibitory control than those who remain abstinent. Little is known about neural activation during inhibitory control tasks in the presence of drug-related cues. In the current study, tobacco smokers (SMK; n = 22) and non-smoking controls (CON; n = 19) completed a Go/NoGo task involving smoking cues during a functional magnetic resonance imaging (fMRI) scan. Following the scan session, smokers were required to quit smoking, and maintenance of abstinence was evaluated as part of a 12-week smoking cessation trial. We evaluated pre-cessation brain activity during NoGo trials in smokers who were versus were not able to quit smoking. We then compared fMRI and inhibitory control measures between smokers and non-smokers. We did not find differences between SMK and CON in performance or activation to smoking or neutral cues. However, compared to SMK who relapsed, SMK who attained biochemically-validated abstinence at the end of the smoking cessation trial had greater neural activation in the anterior insula during NoGo trials specifically with smoking-related cues. Results indicate that within SMK, decreased inhibitory control activation during direct exposure to drug-related stimuli may be a marker of difficulty quitting and relapse vulnerability.

Differences in germination response to smoke and temperature cues in ‘pyrophyte’ and ‘pyrofuge’ forms of Erica coccinea (Ericaceae)

Many plants in fire-prone ecosystems produce seeds that are cued to germinate after fire. However, fire is not uniform in the landscape, and there are often refugia where fire does not reach, like rocky outcrops or moist valleys. Erica coccinea, a heath shrub from the South African fynbos, has two distinct pyrophyte forms (a resprouter and a seeder) as well as a ‘pyrofuge’ form that only occurs in fire refugia. We measured germination response to smoke and incubation temperature in seeds from pyrophyte (resprouter and seeder) and pyrofuge populations to determine whether these forms responded differently to a fire-cue (smoke) and a general germination cue (temperature). We found that seeds from pyrofuge plants had high germination success (80.9–92.0%) at the lowest incubation temperature (15/8°C 12h day/night cycle) regardless of smoke exposure. In contrast, seeds from pyrophytes (resprouters and seeders) responded strongly to the smoke cue (71.2–95.0%) and were not as limited by temperature. These results show that fire presence and absence is driving divergence of the primary germination cue in Erica coccinea. Given the patchiness of many natural fire regimes worldwide, we expect there may be pyrofuge populations exhibiting a similar divergence of traits in other species and other fire-prone ecosystems.

Salience network coupling is linked to both tobacco smoking and symptoms of attention deficit hyperactivity disorder (ADHD)

IntroductionAttention deficit hyperactivity disorder (ADHD) symptoms, even those below diagnostic threshold, enhance the likelihood of nicotine dependence, suggesting a neurobiological link between disorders. Of particular interest is the salience network (SN), which mediates attention to salient internal/external stimuli to guide behavior and is anchored by the dorsal anterior cingulate cortex (dACC) and bilateral anterior insula (AI). Disrupted interactions between the SN and the default mode (DMN) and central executive networks (CEN) have been noted in both ADHD and nicotine dependence. Further, enhanced intra-SN coupling between the dACC-AI influences aspects of nicotine dependence such as reactivity to smoking cues. MethodsTo identify links between SN functional connectivity and ADHD symptoms in nicotine dependence, we compared 21 nicotine dependent individuals with 17 non-smokers on ADHD symptoms as measured by the ADHD self-report scale (ASRS) and resting state intra and inter-SN functional connectivity. ResultsRelative to healthy controls, nicotine dependent individuals had significantly higher ASRS scores and greater dACC-AI coupling. No group differences were noted on inter-SN network coupling. A significant association was found between ASRS and dACC-AI coupling both in the entire cohort and specifically when evaluating nicotine dependent individuals alone. ConclusionsThe greater ASRS scores in nicotine dependent individuals is in line with existent literature and the stronger dACC-AI coupling in smokers further supports the role of this network in nicotine dependence. The significant association between dACC-AI coupling and ASRS suggests that intra-SN coupling strength may impact neurocognitive functioning associated with both ADHD symptoms and nicotine dependence.

Pioglitazone, a PPARγ agonist, reduces nicotine craving in humans, with marginal effects on abuse potential

Possibly through their actions upon glia, peroxisome proliferator-activated receptor agonists (PPAR) have been shown to alter the abuse potential of addictive drugs in several preclinical models. The current study extends this research into the human laboratory as the first clinical study into the effects of the PPAR gamma agonist, pioglitazone, on the abuse potential of nicotine. Heavy smokers were recruited for this 3-week study. Upon admission, participants were randomized to either active (45mg, n=14) or placebo (0mg, n=13) PIO maintenance conditions for the duration of the study. After 5–7days of stabilization on a 7mg nicotine patch, participants began laboratory testing. On the 1st–4th test days, participants could self-administer cigarettes or receive money by making verbal choices for either option. On the 5th day, participants were administered 10 puffs of their usual brand of cigarette in the morning and later chose between smoking and money by making finger presses on a computer mouse in a progressive ratio self-administration task. Later on the 5th day participants also underwent a smoking cue exposure session. The 8th–11th test days were identical to the 1st–4th test days with the exception that during one of the test weeks de-nicotinized cigarettes were available, and during the other nicotinized cigarettes were available. Nicotinized cigarettes were always administered on the 5th and 12th days. On some measures PIO increased indicators of abuse potential, though this effect was typically not statistically significant. However, PIO did significantly reduce measures of craving.

White matter integrity of central executive network correlates with enhanced brain reactivity to smoking cues.

The attentional bias to smoking cues contributes to smoking cue reactivity and cognitive declines underlines smoking behaviors, which were probably associated with the central executive network (CEN). However, little is known about the implication of the structural connectivity of the CEN in smoking cue reactivity and cognitive control impairments in smokers. In the present study, the white matter structural connectivity of the CEN was quantified in 35 smokers and 26 non-smokers using the diffusion tensor imaging and deterministic fiber tractography methods. Smoking cue reactivity was evaluated using cue exposure tasks, and cognitive control performance was assessed by the Stroop task. Relative to non-smokers, smokers showed increased fractional anisotropy (FA) values of the bilateral CEN fiber tracts. The FA values of left CEN positively correlated with the smoking cue-induced activation of the dorsolateral prefrontal cortex and right middle occipital cortex in smokers. Meanwhile, the FA values of left CEN positively correlated with the incongruent errors during Stroop task in smokers. Collectively, the present study highlighted the role of the structural connectivity of the CEN in smoking cue reactivity and cognitive control performance, which may underpin the attentional bias to smoking cues and cognitive deficits in smokers. The multimodal imaging method by forging links from brain structure to brain function extended the notion that structural connections can modulate the brain activity in specific projection target regions. Hum Brain Mapp 38:6239-6249, 2017. © 2017 Wiley Periodicals, Inc.

Self-efficacy modulates the neural correlates of craving in male smokers and ex-smokers: an fMRI study.

The regulation of cue-induced craving for cigarettes is a key factor in smoking cessation. Outcomes of smoking cessation have been linked to self-efficacy, faith in one's own ability, in smokers. However, no study has examined the neural basis of self-efficacy during the control of craving. We examined whether self-efficacy can affect the neural response to smoking cues in smokers and ex-smokers using functional magnetic resonance imaging. During scanning, participants were instructed (1) to view smoking-related images passively, (2) to view the smoking-related images with a strategy focused on self-efficacy to control cue-induced craving or (3) to view neutral images. In smokers, the self-efficacy strategy significantly reduced self-reported craving. This strategy was related to increased activation in the rostral medial prefrontal cortex (rmPFC) and the pregenual anterior cingulate cortex in smokers compared with ex-smokers. Furthermore, smokers showed increased effective connectivity between rmPFC and hippocampus and between pregenual anterior cingulate cortex and parahippocampus gyrus when employing the self-efficacy strategy compared with ex-smokers. The magnitude of the rmPFC-hippocampus connectivity was positively correlated with self-reported self-efficacy. Our findings suggest that in smokers, self-efficacy is related to activation and connectivity in brain regions involved in regulating craving and self-assessment. The current study provides evidence for understanding the vunderlying cognitive and neurobiological mechanisms involved in the control of craving to smoke cigarettes.

Neural correlates of tobacco cue reactivity predict duration to lapse and continuous abstinence in smoking cessation treatment.

It has been hypothesized that neural reactivity to drug cues in certain limbic/paralimbic regions of the brain is an indicator of addiction severity and a marker for likelihood of success in treatment. To address this question, in the current study, 32 participants (44 percent female) completed a functional magnetic resonance imaging cigarette cue exposure paradigm 2hours after smoking, and then enrolled in a 9-week smoking cessation treatment program. Neural activation to smoking cues was measured in five a priori defined limbic/paralimbic regions previously implicated with cue reactivity across substances. These included regions of the ventral striatum, anterior cingulate cortex and amygdala. Cox proportional hazard modeling was conducted to predict the number of days to first smoking lapse by using neural activation in these regions. Greater neural activation during pre-treatment exposure to smoking cues in the right ventral striatum, the left amygdala, and the anterior cingulate was associated with longer periods of abstinence following cessation. A similar pattern was present for continuous abstinence for the full duration of treatment. While baseline levels of nicotine dependence were strongly associated with treatment outcome, activation in the right ventral striatum predicted duration of abstinence beyond level of nicotine dependence. These results suggest that pre-treatment reactivity to smoking cues in areas associated with cue reactivity may be associated with successfully maintaining abstinence during treatment. This is consistent with models that propose that as addiction becomes more severe, motivational processing shifts from regions that subserve reward salience and learning to regions responsible motor behavior and habit learning.

A smoking-related background helps moderate smokers to focus: An event-related potential study using a Go-NoGo task

ObjectiveCognitive impairment is a major component in addiction. However, research has been inconclusive as to whether this is also the case for smokers. The present study aims at providing electrophysiological clue for altered inhibitory control in smokers and at investigating whether reduced inhibition was more pronounced during exposure to a smoking cue. MethodsERPs were recorded during a visual Go-NoGo task performed by 18 smokers and 23 controls, in which either a frequent Go signal (letter “M”) or a rare No-Go signal (“letter W”) were superimposed on three different long-lasting background contexts: black-neutral, smoking-related and non smoking-related. Results(1) Smokers performed worse and had an earlier NoGo-N2 latency as compared to controls and independently of context, suggesting a general inhibition impairment; (2) with smoking-related backgrounds specifically, smokers made fewer mistakes than they did in other contexts and displayed a larger NoGo P3 amplitude. ConclusionThese data might suggest that background cues related to addiction may help smokers to be more accurate in an inhibition task. SignificanceOur results show the classical inhibitory impairment in smokers as compared to non-smokers. However, our data also suggest that a smoking-related background may bolster the inhibitory ability of smokers specifically.

Resisting the urge to smoke: inhibitory control training in cigarette smokers.

Impaired response inhibition is an important factor in tobacco dependence. We examined the effects of inhibitory control training (ICT) on inhibition, smoking resistance and cigarette use. Smokers (n = 55) abstained from smoking for 12 h prior to testing. On the test day, participants recorded cigarette use and completed pre-training measures of global and cue-specific (smoking-related) response inhibition. Participants were randomized to either an active or a control ICT group. The active group was required to repeatedly inhibit a response towards smoking cues (100%), while the control group was required to inhibit a response towards smoking and neutral cues with equal frequency (50%). Participants performed post-training measures of response inhibition, smoking resistance and cigarette use. Inhibition data did not indicate time (pre-training, post-training) × group (active training, control training) or time × group × cue (smoking, neutral) interactions. There was weak evidence that smokers in the active group were more likely to resist smoking than those in the control group. Cigarette use data did not indicate a time × group interaction. Our data suggest that ICT may enhance the ability to resist smoking, indicating that training may be a promising adjunct to smoking pharmacotherapy.

Effect of attentional retraining on cognition, craving, and smoking in African American smokers.

African American cigarette smokers have lower rates of cessation than Whites and live in communities with a higher number of tobacco advertisements. Exposure to smoking cues may promote smoking and undermine cessation. It may be possible to reduce attention to smoking cues ("attentional bias"). In this study, we investigated the effect of attentional retraining (AR) on attentional bias and smoking in African American smokers. Nontreatment- seeking African American smokers (N = 64) were randomly assigned to an AR or control condition. Participants were given a mobile device for 2 weeks and prompted to complete up to 3 AR (or control) trainings per day. Participants completed assessments of attentional bias, craving, and smoking both in the lab and in the field. Participants in the AR and control conditions completed an average of 29.07 AR (SD = 12.48) and 30.61 control training tasks (SD = 13.07), respectively. AR reduced attentional bias assessed in the laboratory, F(1, 126) = 9.20, p = .003, and field, F(1, 374) = 6.18, p = .01. This effect generalized to new stimuli, but not to new tasks. AR did not significantly reduce craving or biological measures of smoking. Smoking assessed on the mobile device declined over days in the AR group, F(1, 26) = 10.95, p = .003, but not in the control group, F(1, 27) = 0.02, p = .89. Two weeks of AR administered on a mobile device reduced attentional bias in African American smokers and had mixed effects on smoking. (PsycINFO Database Record

Virtual Reality Smoking Cessation–Designed for Teens, by Teens

Introduction: Today, about 90% of adult smokers started smoking before the age of 18. As the largest preventable cause of disease and death in the United States, tobacco use accounts for nearly 500,000 deaths and hundreds of billions of dollars to care for smoking-related illnesses every year. While most smoking cessation programs are geared toward adults, there is a void in attempts to curb teen smoking. Objective: With funding from the National Institute on Drug Abuse, the Virtual Reality Medical Center (VRMC) sought to create a more effective way to help teens quit smoking. Utilizing cue exposure therapy to eliminate the association of smoking with objects and activities, the program uses virtual environments containing smoking cues to elicit the addictive behaviors and teach the users how to recognize and resist these triggers. Method: In a novel approach, VRMC recruited students from a local high school to aid in the design and development of virtual worlds in order to create an entertaining and effective program for teens. Researchers and the participants of this TeenSmoking program created a variety of anti-smoking environments ranging from scenarios at home, to peer pressure situations at school, all intended to elicit and educate users on addictive smoking behaviors. Conclusion: With past clinical success, researchers at VRMC hope to continue to implement widely available teen smoking cessation programs with enhanced usability, graphics, and multiplayer functionality. Overall, researchers hope to advance more comprehensive use of virtual reality to curb teen smoking addictions.

Revisiting the role of the insula and smoking cue-reactivity in relapse: A replication and extension of neuroimaging findings

IntroductionThe ability to direct smoking cessation treatment based on neuroscientific findings holds incredible promise. However, there is a strong need for consistency across studies to confirm neurobiological targets. While our prior work implicated enhanced insula reactivity to smoking cues in tobacco smoking relapse vulnerability, this finding has not been confirmed. MethodUsing functional magnetic resonance imaging (fMRI), we evaluated the pre-cessation brain reactivity to smoking vs. neutral cues in nicotine dependent smokers who were and were not able to maintain subsequent abstinence. ResultsOf the 23 (7 women) individuals assessed, 13 relapsed and there were no demographic differences between those who did and did not relapse. However, smokers who relapsed showed enhanced reactivity to smoking cues in the right insula and dorsal striatum, showing significant overlap between our current and prior work despite methodological differences, including the fact that our previous work only included women. ConclusionThe current work supports our prior results and builds on the concept that the insula and dorsal striatum work in concert to maintain nicotine dependence. Specifically, dorsal striatal-mediated habitual responding may be triggered both by the external drug-associated cues, and the insula-mediated internal states that provide additional context motivating drug use. This replicated finding also mirrors preclinical work that finds the same individualized distinction, as only some rodents attribute incentive salience to drug cues and are more likely to reinstate drug seeking after extinction. To effectively treat addiction, these individual characteristics and their underlying neurobiological foundations must be considered.

Multi-site exploration of sex differences in brain reactivity to smoking cues: Consensus across sites and methodologies

BackgroundBiological sex influences cigarette smoking behavior. More men than women smoke, but women have a harder time quitting. Sex differences in smoking cue (SC) reactivity may underlie such behavioral differences. However, the influence of sex on brain reactivity to SCs has yielded inconsistent findings suggesting the need for continued study. Here, we investigated the effect of sex on SC reactivity across two sites using different imaging modalities and SC stimulus types. MethodsPseudo-continuous arterial spin-labeled (pCASL) perfusion functional magnetic resonance imaging (fMRI) was used to assess brain responses to SC versus non-SC videos in 40 smokers (23 females) at the University of Pennsylvania. BOLD fMRI was used to assess brain responses to SC versus non-SC still images in 32 smokers (18 females) at McLean Hospital. Brain reactivity to SCs was compared between men and women and was correlated with SC-induced craving. ResultsIn both cohorts, males showed higher SC versus non-SC reactivity compared to females in reward-related brain regions (i.e., ventral striatum/ventral pallidum, ventral medial prefrontal cortex). Brain activation during SC versus non-SC exposure correlated positively with SC-induced subjective craving in males, but not females. ConclusionsThe current work provides much needed replication and validation of sex differences in SC-reactivity. These findings also add to a body of literature showing that men have greater reward-related brain activation to drug cues across drug classes. Such sex differences confirm the need to consider sex not only when evaluating SC-reactivity but when examining nicotine dependence etiology and treatment.

Disgust but not Health Anxiety Graphic Warning Labels Reduce Motivated Attention in Smokers: A Study of P300 and Late Positive Potential Responses.

Graphic health warning labels (GHWLs) on tobacco products attempt to leverage avoidance-promoting emotions, such as anxiety and disgust, to encourage cessation. Prior studies have relied on self-report or attentional metrics that may not accurately illuminate GHWLs' ability to motivate change. This report evaluates the impact of disgust- and anxiety-based GHWLs on electroencephalograph (EEG) measures of motivated attention among two groups of smokers-those that report higher versus lower cigarette dependence. We hypothesized that both anxiety and disgust GHWLs would reduce appetitive attention, as indexed by lowered P300 (P3) and late positive potential (LPP) activations. Sixty-one smokers provided demographic and smoking history before completing an oddball paradigm consisting of three counterbalanced stimuli blocks. Each block (100 trials) contained a neutral, GHWL-anxiety, or GHWL-disgust frequent image and a smoking cue as the oddball image (20%). Oddball trials for each block were averaged, P3 and LPP were identified at midline electrode positions (Fz, Cz, and Pz), and mean amplitude was analyzed. Separate mixed-model ANOVAs of P3 and LPP reactivity revealed disgust-focused GHWLs reduced motivated attentional processing. Conversely, the anxiety-focused GHWL appeared to increase the salience of the smoking cue (Fz only). Less-dependent smokers showed lower P3 reactivity than those with higher dependence at Fz, but greater P3 reactivity at Cz and Pz. These results extend prior work in demonstrating that disgust, but not anxiety-based GHWLs, may reduce EEG-assessed motivated attention to smoking cues. Disgust may thus represent a more fruitful target for public health cessation efforts. Most GHWL evaluations have focused on fear (or anxiety) elicitation rather than disgust, an emotion that may have a unique link to smoking, having evolved specifically to facilitate the avoidance of contaminants via oral incorporation. Analyses of P300 and LPP responses to GHWLs suggest that disgust-focused images interfere with the EEG-indexed attentional processing of smoking cues and do so better than health anxiety-focused messages. However, interaction effects at different electrode sites indicated that GHWLs have complex effects in more versus less-dependent smokers and that an understanding of how smoking cues and anti-smoking imagery become associated over time is needed to identify relevant targets for public health efforts.