Neural biomarkers for assessing different types of imagery in pictorial health warning labels for cigarette packaging: a cross-sectional study

Impact of text-only versus large text-and-picture alcohol warning formats: A functional magnetic resonance imaging study in French young male drinkers

BACKGROUND

Although the World Health Organization recommends visible and clear warning labels about the risks of alcohol consumption on containers and advertising, many of the currently used labels are too small to be visible. This study investigated the brain activity (using fMRI) and alcohol consumption intentions of French young men exposed to two warning formats displayed on alcoholic beverage advertisements: a small Text-only Alcohol Warning (TAW) currently used in many countries, and a larger text-and-picture alcohol warning (PAW).

METHODS

Seventy-four eligible 18-25-year-old male drinkers completed a face-to-face individual visit with a physician expert in addiction medicine. This was followed by the fMRI session during which they viewed 288 stimuli [96 alcohol advertisements with TAWs, the same 96 advertisements with PAWs, and 96 water advertisements (controls)] for 3 s each. If the advertisement made participants want ("yes")/do not want ("no") to consume the product, they pressed the corresponding button (self-report responses). The number of "yes" responses was compared between advertisement types with a paired sample t-test. Whole-brain and region-of-interest (ROI) analyses of the fMRI data were performed.

RESULTS

Whole-brain BOLD fMRI highlighted contrasting effects of PAWs and TAWs. Compared with TAWs, PAWs elicited more activation in the precuneus, angular gyrus, occipital, frontal and temporal areas, and less activation in the nucleus accumbens, ventral tegmental areas, and putamen areas (regions of the reward circuit). The ROI analysis confirmed less activation in the reward circuit (left and right ventral tegmental areas, left and right nucleus accumbens) when viewing PAWs than TAWs. Analysis of the self-report responses indicated that the desire to consume the advertised alcohol product was lower when PAWs were viewed (compared with TAWs) (T = 8.18, p < 10-11).

CONCLUSIONS

This is the first fMRI study to assess the effect of different alcohol warning formats. Our findings show that compared with TAWs, stronger PAWs in advertisements elicited less activity in key regions of the reward system. This suggests that the effects may influence the desire to consume alcohol products (self-report response analysis). These results could help policymakers who are interested in developing more effective labeling measures that target young people.

Signs of Warning: Do Health Warning Messages on Sweets Affect the Neural Prefrontal Cortex Activity?

In the global attempt to combat rising obesity rates, the introduction of health warning messages on food products is discussed as one possible approach. However, the perception of graphical health warning messages in the food context and the possible impact that they may have, in particular at the neuronal level, have hardly been studied. Therefore, the aim of this explorative study was to examine consumers’ reactions (measured as neuronal activity and subjective reporting) of two different types of graphical health warning messages on sweets compared to sweets without warning messages. One type used the red road traffic stop sign as graphical information (“Stop”), while the other one used shocking pictures (“Shock”), an approach similar to the images on cigarette packages. The neural response of 78 participants was examined with the neuroimaging technique functional near-infrared spectroscopy (fNIRS). Different hemodynamic responses in the orbitofrontal cortex (OFC), the frontopolar cortex (FOC), and the dorsolateral prefrontal cortex (dlPFC) were observed, regions which are associated with reward evaluation, social behavior consequences, and self-control. Further, the health warning messages were actively and emotionally remembered by the participants. These findings point to an interesting health information strategy, which should be explored and discussed further.

Adolescent Attention to Disgust Visuals in Cigarette Graphic Warning Labels

PURPOSE

Adolescents are often a target audience for disgust-eliciting antismoking messages, including graphic warning labels (GWLs) on cigarette packages. Yet, few studies have examined how adolescents attend and respond to disgust imagery frequently depicted in these messages.

METHODS

A within-subjects eye-tracking experiment with middle school youth (N = 436) examined attention for GWLs that feature disgust versus nondisgust images. Hypotheses were based on emotion theory and previous findings with adult participants. This study also tested whether living with a smoker moderated effects of attention on negative emotions and risk beliefs.

RESULTS

Participants paid similar levels of attention to warnings with disgust visuals as they did warnings with nondisgust visuals, accounting for other differences in the warnings. The presence of a disgust visual drew greater attention to the warning image and reduced attention for the warning text. These viewing patterns were similar for youth who live with a smoker and those who do not. Attention to disgust imagery was the only attentional factor to predict negative emotional reactions, and this relationship was driven by results observed among youth who live with a smoker. Attention to neither image nor text predicted risk beliefs.

CONCLUSIONS

GWLs with disgust imagery do not trigger more or less attention to the overall warnings but do influence allocation of attention to images over text. Future work should confirm whether attention to disgust imagery itself is important for triggering negative emotional responses, particularly with youth for whom the message is more personally relevant.

Brain Responses to Anti-Smoking Health Warnings In Youth

Purpose of the Review

Adolescents and young adults are a critical target for smoking prevention efforts. Health education is a key approach to these efforts, yet little is known about how adolescents and young adults process health information. One novel approach to understanding the neurobiological mechanisms of cognitive processing of public health communications is to use neuroimaging techniques to map the brain regions involved and make inferences about the neural systems engaged in the processing of health information. We reviewed recent studies that employed functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) to examine the brain responses of adolescents and young adults to anti-smoking health messages and videos.

Findings

This narrative literature review found that the medial prefrontal cortex, amygdala, and hippocampus were the brain regions most commonly engaged in response to health warnings. Developmental factors modulate the relationship between brain regions, regulated emotional reaction, and frontal regions that are responsible for decision making.

Summary

Research that integrates neurophysiology and behavior to study adolescent and young adult neurocognitive responses to health messaging is an important tool for identifying optimal methods to communicate the health hazards of smoking to this vulnerable population.

Using Neuroscience to Inform Tobacco Control Policy

INTRODUCTION

Techniques employed in the field of neuroscience, such as eye tracking, electroencephalography, and functional magnetic resonance imaging, have been important in informing our understanding of the cognitive mechanisms underlying tobacco smoking. These techniques are now increasingly being used to investigate the likely impact of tobacco control policies.

AIMS AND METHODS

In this narrative review, we outline the value of these methodological approaches in answering policy-relevant tobacco control research questions, with a particular focus on their use in examining the impact of standardized cigarette packaging and health warnings. We also examine the limitations of these methodologies and provide examples of how they can be used to answer other policy-relevant questions.

RESULTS

We argue that neuroscience techniques can provide more objective evidence of the impacts of policy measures, allow investigation where it is not possible to conduct behavioral manipulations, and facilitate a deeper understanding of the cognitive mechanisms underlying the impacts of tobacco control policies such as standardized packaging, health warnings, point-of-sale displays, and mass media campaigns.

CONCLUSIONS

Rather than replacing more traditional methods of examining tobacco control measures, such as observational experiments, surveys, and questionnaires, neuroscience techniques can complement and extend these methods.

IMPLICATIONS

Neuroscience techniques facilitate objective examination of the mechanisms underlying the impacts of tobacco control measures. These techniques can therefore complement and extend other methodologies typically used in this field, such as observational experiments, surveys, and questionnaires.

Size matters in the case of graphic health warnings: Evidence from physiological measures

OBJECTIVES

>50 countries use graphic health warnings (GHWs) with the minimum size that is recommended by the World Health Organization (WHO). The aim of the present study was to evaluate the effect of the size of GHWs on physiological responses that serve as indices of arousal and aversive motivation in nonsmokers, weekly smokers, and daily smokers.

METHODS

The skin conductance response, corrugator muscle activity, and startle reflex were recorded in 35 nonsmokers, 35 weekly smokers, and 35 daily smokers while they observed pictures of cigarette packs without GHWs, cigarette packs with GHWs that covered 30% of the pack, and cigarette packs with GHWs that covered 60% of the pack.

RESULTS

Cigarette packs with 30% GHWs did not generate significantly higher responses on any of the physiological measures compared with cigarette packs without GHWs. Conversely, cigarette packs with GHWs that covered 60% of the pack generated a greater skin conductance response, greater corrugator muscle activity, and an increase in the startle reflex compared with cigarette packs without GHWs. No significant differences were found between groups in any of the physiological measures.

CONCLUSIONS

The minimum size of GHW that is recommended by the WHO is insufficient to generate an emotional response that favors avoidance of the cigarette pack. GHW that cover 60% of the cigarette pack significantly reduced the attractiveness of the tobacco packaging and generated greater arousal responses.

Effect of smoking status on neuronal responses to graphic cigarette warning labels

Background

Smoking is responsible for a large proportion of cancer, respiratory and cardiovascular deaths. Nevertheless the health risks of smoking are still underestimated in many smokers. The present study aimed to examine neurobiological responses to graphical warnings on cigarette packings in non-smokers and patients with tobacco dependence.

Methods

Twenty non-smokers and twenty-four patients with tobacco dependence participated in a functional MRI study during that pictures of different categories were presented ((a) EU-warning pictures, (b) text-only warnings, (c) neutral pictures with short information). Patients contributed twice in the experiment (after 10 hours nicotine withdrawal / about 5 minutes after nicotine consumption).

Results

Smokers during withdrawal demonstrated increased neuronal responses predominantly in subcortical, temporal and frontal brain regions that are associated with emotional and cognitive processes during the presentation of graphical warnings compared to neutral pictures. In smokers after smoking and non-smokers, the differences between graphical warnings and neutral pictures were increased compared to smokers during withdrawal. The comparison of the graphical warnings with text-only labels demonstrated the importance of affective brain regions especially in smokers after smoking and in non-smokers. During withdrawal, the neural responses associated with graphical warnings and text-only labels differed only marginally.

Discussion and conclusion

The results suggest that emotional and cognitive reactions to graphical warnings are predominantly seen in smokers after smoking and in non-smokers. The impact of these pictures during withdrawal seems to be less pronounced; in this case, more unspecific processes seem to be important, including the projection of sensory signals to the cerebral cortex.

Which type of tobacco product warning imagery is more effective and sustainable over time? A longitudinal assessment of smokers in Canada, Australia and Mexico

OBJECTIVE

This study examined smokers' responses to pictorial health warnings (PHWs) with different types of imagery under natural exposure conditions.

METHODS

Adult smokers from online panels in Canada (n=2357), Australia (n=1671) and Mexico (n=2537) were surveyed every 4 months from 2012 to 2013. Participants were shown PHWs on packs in their respective countries and asked about: (1) noticing PHWs; (2) negative affects towards PHWs; (3) believability of PHWs; (4) PHW-stimulated discussions; and (5) quit motivation due to PHWs. Country-specific generalised estimating equation models regressed these outcomes on time (ie, survey wave), PHW imagery type (ie, symbolic representations of risk, suffering from smoking and graphic depictions of bodily harm) and interactions between them.

RESULTS

In all countries, PHW responses did not significantly change over time, except for increased noticing PHWs in Canada and Mexico, increased negative affect in Australia and decreased negative affect in Mexico. For all outcomes, symbolic PHWs were rated lower than suffering and graphic PHWs in Canada (the only country with symbolic PHWs). Graphic PHWs were rated higher than suffering PHWs for negative affect (all countries), discussions (Canada) and quit motivation (Australia). Suffering PHWs were rated higher than graphic PHWs for noticing PHWs (Canada), believability (all countries), discussions (AustraliaandMexico) and quit motivation (Mexico). Changes in noticing, believability and discussions varied somewhat by imagery type across countries.

CONCLUSIONS

The different PHW imagery appears to have different pathways of influence on adult smokers. Reactions to specific PHWs are similar over 1-2 years, suggesting that wear-out of PHW effects is due to decreased attention rather than the diminishing effectiveness of content.

Smokers' Neurological Responses to Novel and Repeated Health Warning Labels (HWLs) From Cigarette Packages

Graphic health warning labels (HWLs) depicting bodily injury due to smoking are effective for producing changes in affect, cognition and smoking behavior in adult smokers. However, little is known about the effects of repeated presentation of graphic HWL's on the aforementioned processes. The goal of this study was to examine neural and behavioral responses to graphic HWL's and evaluate whether the repeated presentation of graphic HWL's leads to repetition suppression (RS). Smokers (N = 16) performed an event-related HWL cue task while blood oxygen level dependent (BOLD) signal was collected during a functional magnetic resonance imaging (fMRI) experimental session. Consistent with prior literature, graphic HWL's, as compared to scrambled images, elicited increased BOLD response in brain regions involved in self-referential and emotion processing. Importantly, BOLD response at sites in this network diminished during repeated presentation of the same HWL. These findings suggest that while novel graphic HWL's may have a significant effect on smokers' brain activity, repeated presentation may lead to muted responses and thus limit their potential to induce behavioral change.

Brain Activation in Response to Personalized Behavioral and Physiological Feedback From Self-Monitoring Technology: Pilot Study

Background

The recent surge in commercially available wearable technology has allowed real-time self-monitoring of behavior (eg, physical activity) and physiology (eg, glucose levels). However, there is limited neuroimaging work (ie, functional magnetic resonance imaging [fMRI]) to identify how people’s brains respond to receiving this personalized health feedback and how this impacts subsequent behavior.

Objective

Identify regions of the brain activated and examine associations between activation and behavior.

Methods

This was a pilot study to assess physical activity, sedentary time, and glucose levels over 14 days in 33 adults (aged 30 to 60 years). Extracted accelerometry, inclinometry, and interstitial glucose data informed the construction of personalized feedback messages (eg, average number of steps per day). These messages were subsequently presented visually to participants during fMRI. Participant physical activity levels and sedentary time were assessed again for 8 days following exposure to this personalized feedback.

Results

Independent tests identified significant activations within the prefrontal cortex in response to glucose feedback compared with behavioral feedback (P<.001). Reductions in mean sedentary time (589.0 vs 560.0 minutes per day, P=.014) were observed. Activation in the subgyral area had a moderate correlation with minutes of moderate-to-vigorous physical activity (r=0.392, P=.043).

Conclusion

Presenting personalized glucose feedback resulted in significantly more brain activation when compared with behavior. Participants reduced time spent sedentary at follow-up. Research on deploying behavioral and physiological feedback warrants further investigation.

Path analysis of warning label effects on negative emotions and quit attempts: A longitudinal study of smokers in Australia, Canada, Mexico, and the US

BACKGROUND

Cigarette pack health warning labels can elicit negative emotions among smokers, yet little is known about how these negative emotions influence behavior change.

OBJECTIVE

Guided by psychological theories emphasizing the role of emotions on risk concern and behavior change, we investigated whether smokers who reported stronger negative emotional responses when viewing warnings reported stronger responses to warnings in daily life and were more likely to try to quit at follow-up.

METHODS

We analyzed data from 5439 adult smokers from Australia, Canada, Mexico, and the US, who were surveyed every four months from September 2012 to September 2014. Participants were shown warnings already implemented on packs in their country and reported negative emotional responses (i.e., fear, disgust, worry), which were averaged (range = 1 to 9). Country-stratified logistic and linear generalized estimating equations were used to analyze the effect of negative emotional responses on self-reported responses to warnings in daily life (i.e., attention, risk concern, avoidance of warnings, forgoing planned cigarettes) and quit attempts at follow-up. Models were adjusted for socio-demographic and smoking-related characteristics, survey wave, and the number of prior surveys answered.

RESULTS

Smokers who reported stronger negative emotions were more likely to make quit attempts at follow-up (Adjusted ORs ranged from 1.09 [95% CI 1.04 to 1.14] to 1.17 [95% CI 1.12 to 1.23]; p < .001) than those who reported lower negative emotions. This relationship was mediated through attention to warnings and behavioral responses to warnings. There was no significant interaction of negative emotions with self-efficacy or nicotine dependence.

CONCLUSION

Negative emotions elicited by warnings encourage behavior change, promoting attention to warnings and behavioral responses that positively predict quit attempts.

Can functional magnetic resonance imaging studies help with the optimization of health messaging for lifestyle behavior change? A systematic review

Unhealthy behaviors, including smoking, poor nutrition, excessive alcohol consumption, physical inactivity and sedentary lifestyles, are global risk factors for non-communicable diseases and premature death. Functional magnetic resonance imaging (fMRI) offers a unique approach to optimize health messages by examining how the brain responds to information relating to health. Our aim was to systematically review fMRI studies that have investigated variations in brain activation in response to health messages relating to (i) smoking; (ii) alcohol consumption; (iii) physical activity; (iv) diet; and (v) sedentary behavior. The electronic databases used were Medline/PubMed, Web of Science (Core Collection), PsychINFO, SPORTDiscuss, Cochrane Library and Open Grey. Studies were included if they investigated subjects aged ≥10years and were published before January 2017. Of the 13,836 studies identified in the database search, 18 studies (smoking k=15; diet k=2; physical activity/sedentary behavior k=1) were included in the review. The prefrontal cortex was activated in seven (47%) of the smoking-related studies and the physical activity study. Results suggest that activation of the ventromedial, dorsolateral and medial prefrontal cortex regions were predictive of subsequent behavior change following exposure to aversive anti-smoking stimuli. Studies investigating the neurological responses to anti-smoking material were most abundant. Of note, the prefrontal cortex and amygdala were most commonly activated in response to health messages across lifestyle behaviors. The review highlights an important disparity between research focusing on different lifestyle behaviors. Insights from smoking literature suggest fMRI may help to optimize health messaging in relation to other lifestyle behaviors.

Neural mechanisms underlying visual attention to health warnings on branded and plain cigarette packs

AIMS

To (1) test if activation in brain regions related to reward (nucleus accumbens) and emotion (amygdala) differ when branded and plain packs of cigarettes are viewed, (2) test whether these activation patterns differ by smoking status and (3) examine whether activation patterns differ as a function of visual attention to health warning labels on cigarette packs.

DESIGN

Cross-sectional observational study combining functional magnetic resonance imaging (fMRI) with eye-tracking. Non-smokers, weekly smokers and daily smokers performed a memory task on branded and plain cigarette packs with pictorial health warnings presented in an event-related design.

SETTING

Clinical Research and Imaging Centre, University of Bristol, UK.

PARTICIPANTS

Non-smokers, weekly smokers and daily smokers (n = 72) were tested. After exclusions, data from 19 non-smokers, 19 weekly smokers and 20 daily smokers were analysed.

MEASUREMENTS

Brain activity was assessed in whole brain analyses and in pre-specified masked analyses in the amygdala and nucleus accumbens. On-line eye-tracking during scanning recorded visual attention to health warnings.

FINDINGS

There was no evidence for a main effect of pack type or smoking status in either the nucleus accumbens or amygdala, and this was unchanged when taking account of visual attention to health warnings. However, there was evidence for an interaction, such that we observed increased activation in the right amygdala when viewing branded as compared with plain packs among weekly smokers (P = 0.003). When taking into account visual attention to health warnings, we observed higher levels of activation in the visual cortex in response to plain packaging compared with branded packaging of cigarettes (P = 0.020).

CONCLUSIONS

Based on functional magnetic resonance imaging and eye-tracking data, health warnings appear to be more salient on 'plain' cigarette packs than branded packs.

Neural response to pictorial health warning labels can predict smoking behavioral change

In order to improve our understanding of how pictorial health warning labels (HWLs) influence smoking behavior, we examined whether brain activity helps to explain smoking behavior above and beyond self-reported effectiveness of HWLs. We measured the neural response in the ventromedial prefrontal cortex (vmPFC) and the amygdala while adult smokers viewed HWLs. Two weeks later, participants’ self-reported smoking behavior and biomarkers of smoking behavior were reassessed. We compared multiple models predicting change in self-reported smoking behavior (cigarettes per day [CPD]) and change in a biomarkers of smoke exposure (expired carbon monoxide [CO]). Brain activity in the vmPFC and amygdala not only predicted changes in CO, but also accounted for outcome variance above and beyond self-report data. Neural data were most useful in predicting behavioral change as quantified by the objective biomarker (CO). This pattern of activity was significantly modulated by individuals’ intention to quit. The finding that both cognitive (vmPFC) and affective (amygdala) brain areas contributed to these models supports the idea that smokers respond to HWLs in a cognitive-affective manner. Based on our findings, researchers may wish to consider using neural data from both cognitive and affective networks when attempting to predict behavioral change in certain populations (e.g. cigarette smokers).

Young Adult Smokers' Neural Response to Graphic Cigarette Warning Labels

Introduction

The study examined young adult smokers' neural response to graphic warning labels (GWLs) on cigarette packs using functional magnetic resonance imaging (fMRI).

Methods

Nineteen young adult smokers (M age 22.9, 52.6% male, 68.4% non-white, M 4.3 cigarettes/day) completed pre-scan, self-report measures of demographics, cigarette smoking behavior, and nicotine dependence, and an fMRI scanning session. During the scanning session participants viewed cigarette pack images (total 64 stimuli, viewed 4 s each) that varied based on the warning label (graphic or visually occluded control) and pack branding (branded or plain packaging) in an event-related experimental design. Participants reported motivation to quit (MTQ) in response to each image using a push-button control. Whole-brain blood oxygenation level-dependent (BOLD) functional images were acquired during the task.

Results

GWLs produced significantly greater self-reported MTQ than control warnings (p < .001). Imaging data indicate stronger neural activation in response to GWLs than the control warnings at a cluster-corrected threshold p < .001 in medial prefrontal cortex, amygdala, medial temporal lobe, and occipital cortex. There were no significant differences in response to warnings on branded versus plain cigarette packages.

Conclusions

In this sample of young adult smokers, GWLs promoted neural activation in brain regions involved in cognitive and affective decision-making and memory formation and the effects of GWLs did not differ on branded or plain cigarette packaging. These findings complement other recent neuroimaging GWL studies conducted with older adult smokers and with adolescents by demonstrating similar patterns of neural activation in response to GWLs among young adult smokers.

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Novel data on the neurobiological effect of graphic cigarette warning labels (GWLs)

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GWLs produced activation indicating emotional and cognitive decision-making.

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Activation in response to GWLs also indicates memory formation.

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No differences in neural activity for GWLs on branded or plain cigarette packages

Depressive symptoms and responses to cigarette pack warning labels among Mexican smokers

OBJECTIVE

We examine whether having depressive symptoms (DS) is associated with different responses to cigarette package health warning labels (HWLs) before and after the implementation of pictorial HWLs in Mexico.

METHOD

We analyze data from adult smokers from Wave 4 and Wave 5 (n = 1,340) of the International Tobacco Control Policy Evaluation Project in Mexico. Seven Center for Epidemiological Studies Depression Scale (CES-D) items assessed DS, with scores ≥7 indicating elevated DS. Outcomes included: attention to HWLs, cognitive responses to HWLs, tobacco constituents awareness, putting off smoking due to HWLs, avoidance of HWLs, and awareness of telephone support for cessation (i.e., quitlines). Mixed effects models were used to assess main and interactive effects of DS and time (i.e., survey wave) on each outcome.

RESULTS

All HWL responses increased over time, except putting off smoking. Statistically significant interactions were found between DS and time for models of tobacco constituents awareness (b = -0.36, SE = 0.15, p = .022), putting off smoking (OR = 0.41, 95% CI [0.25, 0.66]), avoidance of HWLs (OR = 1.84, 95% CI [1.03, 3.29]), and quitline awareness (OR = 0.35, 95% CI [0.21, 0.56]). Compared to smokers with low DS, smokers with elevated DS reported stronger HWL responses at baseline; however, HWL responses increased over time among smokers with low DS, whereas HWL responses showed little or no change among smokers with elevated DS.

DISCUSSION

Population-level increases in HWL responses after pictorial HWLs were introduced in Mexico appeared mostly limited to smokers with low DS. In general, however, smokers with elevated DS reported equivalent or stronger HWL responses than smokers with low DS.