Electrophysiological indices of biased cognitive processing of substance-related cues: a meta-analysis

Approach bias in individuals with Internet gaming disorder: Evidence from an event-related potential-based approach-avoid task

Individuals with Internet gaming disorder (IGD) often exhibit an approach bias towards gaming cues compared to non-gaming cues. Although previous studies suggested a positive correlation between approach bias and the severity of game use, the neuropsychological mechanisms that underpin the automatic action tendencies remain largely unexplored. The present study measured event-related potentials (ERPs) in 22 IGD and 23 healthy control (HC) participants who met the inclusion criteria, both groups conducted the Stimulus-Response Compatibility task (SRC), with their ERPs recorded during the task. Results revealed that the IGD group showed a significantly larger approach bias towards gaming cues (avoidance versus approach reaction time) compared to the HC group. The amplitude of P300 significantly increased, whereas N100 significantly decreased for game-approach compared to game-avoid for IGD compared to HC participants. The findings suggested that the enhanced integrated motivational value under compatible conditions as well as increased stimulus-response conflicts under incompatible conditions may contribute to the approach bias in IGD individuals. Further investigation on the intervention is prompted through longitudinal studies.

Variants of the P3 event-related potential operate as indicators of distinct mechanisms contributing to problematic alcohol use

Considerable research has linked relative reduction in the amplitude of the P3 event-related potential (ERP) during cognitive task performance (i.e., Target-P3) with increased risk of alcohol-related problems. A separate literature indicates that a relative increase in the amplitude of the P3 elicited by cues signaling alcohol availability (i.e., ACR-P3) also is associated with alcohol use and problems. To date, no research has integrated these seemingly discrepant findings. Here, we aimed to demonstrate that P3 amplitudes elicited in different task contexts reflect distinct domains of functioning relevant to problematic alcohol involvement (PAI), and therefore can inform heterogeneity in the etiology of PAI. 156 emerging adults (61% women; 88% White/Non-Hispanic) completed a mental rotation task and a picture-viewing task while ERPs were recorded. Participants also completed questionnaire measures of trait disinhibition, alcohol use, and alcohol-related problems. Findings from regression analyses indicated that (a) Target-P3 was negatively associated and ACR-P3 was positively associated with a PAI latent variable; (b) the two P3s accounted for unique variance in PAI, beyond that accounted for by recent drinking; and (c) the association between Target-P3 and PAI-but not ACR-P3 and PAI-was statistically mediated by trait disinhibition. The present findings highlight the unique contributions of distinct functional domains associated with disinhibition and incentive salience in the etiology of PAI. Moreover, findings are consistent with a nuanced understanding of the P3 ERP, whereby its specific meaning varies according to the task context in which it is elicited.

A meta-analysis of electrophysiological biomarkers of reward and error monitoring in substance misuse

Substance use disorders are characterized by marked changes in reward and error processing. The primary objective of this meta-analysis was to estimate effect sizes for the reward positivity (RewP) and error-related negativity (ERN), two event-related potential indicators of outcome monitoring, in substance users compared to controls. The secondary objective was to test for moderation by demographic, substance type, and EEG experiment parameters. Final PubMed searches were performed in August 2023. Inclusion criteria were substance use disorder/dependence or validated self-report of substance misuse, RewP/ERN means available, healthy control comparison group, non-acute drug study, peer-reviewed journal, English language, and human participants. Selection bias was tested through modified Egger's regression and exploratory 3-parameter selection model tests. The RewP results (19 studies, 1641 participants) did not support an overall effect (Hedges' g = 0.07, 95% CI [-0.44, 0.58], p = .777) and nor effect of any moderators. The ERN results (20 studies, 1022 participants) indicated no significant overall effect (g = 0.41, 95%CI [-0.05, 0.88]). Subgroup analyses indicated that cocaine users had a blunted ERN compared to controls (g = 1.12, 95%CI [0.77, 1.47]). There was limited evidence for publication/small study bias. Although the results indicate a potential dissociation between substance types, this meta-analysis revealed the need for additional research on the RewP/ERN in substance using populations and for better designed experiments that adequately address research questions.

The effect of cognitive reappraisal on food craving and consumption: Does working memory capacity influence reappraisal ability? An event-related potential study

Regulating cravings for unhealthy foods in favour of healthier options is essential for weight management. Cognitive reappraisal, which involves changing the meaning of a stimulus to modify its emotional impact, has shown promise for regulating food craving and consumption. Eighty participants were presented with high-calorie (HC) and low-calorie (LC) food pictures preceded by cues signalling instructions to naturally view the food (i.e., passive viewing; LOOK) or to imagine the future consequences of consuming that food (i.e., cognitive reappraisal; REGULATE). Participants' subjective craving and event-related potentials (ERPs) were measured, and food consumption after the task was assessed. Participants' working memory capacity (WMC) was measured with the automated Operation Span task. During cognitive reappraisal, cravings for HC foods decreased, whereas cravings for LC foods increased, compared to passive viewing. Cravings for LC and HC foods were correlated with consumptions of LC and HC foods, respectively. Occipital N1 (100-200ms) amplitudes were more negative for LC than for HC pictures, but were not modulated by strategy (LOOK or REGULATE), whereas early posterior negativity (EPN; 200-300ms) was not sensitive to food type (HC or LC) or strategy. Late positive potential (LPP; 400-1000ms) ERPs were largest in the HC-REGULATE condition, possibly due to cognitive processes induced by focusing on the consequences of unhealthy foods. Late LPP (1000-3000ms) was not affected by food type or strategy. LPP amplitudes were not correlated with cravings. WMC was weakly correlated with cravings for LC following reappraisal, suggesting that WMC may influence reappraisal ability. In sum, focusing on future consequences of eating may promote healthier food choices through craving regulation. Further research is needed to examine how regulatory effects evolve over time and how they relate to WMC and brain activity.

Predictive utility of the P3 event-related potential (ERP) response to alcohol cues for ecologically assessed alcohol craving and use

Neural measures of alcohol cue incentive salience have been associated with retrospective reports of riskier alcohol use behaviour and subjective response profiles. This study tested whether the P3 event-related potential (ERP) elicited by alcohol-related cues (ACR-P3) can forecast alcohol use and craving during real-world drinking episodes. Participants (N = 262; Mage  = 19.53; 56% female) completed a laboratory task in which they viewed images of everyday objects (Neutral), non-alcohol drinks (NonAlc) and alcohol beverages (Alc) while EEG was recorded and then completed a 21-day ecological momentary assessment (EMA) protocol in which they recorded alcohol craving and consumption. Anthropometrics were used to derive estimated blood alcohol concentration (eBAC) throughout drinking episodes. Multilevel modelling indicated positive associations between P3 amplitudes elicited by all stimuli and within-episode alcohol use measures (e.g., eBAC, cumulative drinks). Focal follow-up analyses indicated a positive association between AlcP3 amplitude and eBAC within episodes: Larger AlcP3 was associated with a steeper rise in eBAC. This association was robust to controlling for the association between NonAlcP3 and eBAC. AlcP3 also was positively associated with episode-level measures (e.g., max drinks, max eBAC). There were no associations between any P3 variables and EMA-based craving measures. Thus, individual differences in neural measures of alcohol cue incentive salience appear to predict the speed and intensity of alcohol consumption but not reports of craving during real-world alcohol use episodes.

Frontal EEG response to alcohol craving elicited by individually tailored video cues

BACKGROUND

Most findings on the pathophysiology of alcoholism are based on studies using resting-state electroencephalography (EEG). There are few studies on cue-induced craving and on its utility as an electrophysiological index. We examined quantitative EEG (qEEG) activities in alcoholics and social drinkers exposed to video cues and compared their association with subjective alcohol craving and other related psychiatric symptoms, including anxiety and depression.

METHODS

This is a between-subjects design. Adult male alcoholics (n = 34) and healthy social drinkers (n = 33) participated. In a laboratory, EEGs were recorded while the participants were presented with craving-inducing video stimuli. Measures used were the Visual Analog Scale (VAS) for subjective alcohol craving, Alcohol Urge Questionnaire (AUQ), Michigan Alcoholism Screening Test (MAST), Beck Anxiety Inventory (BAI), and Beck Depression Inventory (BDI) scores.

RESULTS

One-way analysis of covariance with age showed that alcoholics had significantly increased beta activity in the right DLPFC region (F4) (F = 4.029, p = 0.049), compared to social drinkers when craving-inducing stimuli were presented. Beta activity at the F4 electrode was positively correlated with AUQ (r = .284, p = 0.021), BAI (r = .398, p = 0.001), BDI (r = .291, p = 0.018), and changes in VAS (r = .292, p = 0.017) scores in both alcoholics and social drinkers. In alcoholics, beta activity was significantly correlated with BAI (r = .392, p = 0.024).

CONCLUSIONS

These findings imply functional importance of hyperarousal and negative emotions upon exposure to craving-inducing cues. Frontal EEG indices with beta power could serve as an objective electrophysiological index of craving induced by individually tailored video cues in alcohol consumption behavior.

Associations of the P300 Event-Related Potentials and Self-Reported Craving in Substance Use Disorders: A Systematic Review

INTRODUCTION

The phenomenon of craving and attention bias towards drug cues is theorized to operate cooperatively, owing to the principles of associative learning. In this context, the conditioned response to drug-related stimuli activates reward mechanisms within the brain, consequently inducing craving and fostering the underlying mechanisms that contribute to relapse in individuals with substance use disorders. Multiple studies have assessed the relationship between attention to substance-related cues and subjective craving through electroencephalography (EEG), but their findings have yet to be synthesized and examined. This review summarizes the association between the amplitude of the P300 event-related potential (ERP) and substance use craving, compares discrepancies in results by type of substance, and discusses gaps in the literature to inform future research.

METHODS

A systematic search was conducted on Embase, Web of Science, CINAHL, and PsychINFO databases. Studies were published in English and included peer-reviewed human research investigating the relationship between EEG P300 ERP and self-reported substance use craving. The included study samples comprised of in treatment or non-treatment-seeking participants who use substances. The primary outcomes of interest were those derived from inferential statistics assessing P300 amplitude and substance use craving.

RESULTS

Ten studies were included in the final search and were organized by substance type: three alcohol, three cocaine, two tobacco, one heroin, and one cannabis. Results were mixed for alcohol and cocaine. Studies on tobacco, heroin, and cannabis use were congruent for associations between the P300 amplitude and craving.

CONCLUSIONS

Overall findings are mixed between studies addressing the association of the EEG P300 amplitude and craving. These results should be considered in the context of the limited sample size, underpowered analyses, and methodological differences that potentially contribute to discrepancies in outcomes. Further research is required to assess the role of craving assessment, EEG methodology, and substance-related factors on the association between P300 amplitude and self-reported craving.

Affective imagery boosts the reward related delta power in hazardous drinkers

The Reward Positivity (RewP) is an event-related potential component with a delta band spectral representation that is elicited by reward receipt. Evidence suggests that RewP is modulated by both reward probability as well as affective valuation ("liking"). Here we determined whether RewP is a marker of enhanced hedonic salience of alcohol images in hazardous drinkers. We recruited 54 participants (Hazardous Drinkers = 28, Control = 26) who completed a reinforcement learning task with affective versus alcohol imagery during feedback. The learning task used images of puppies vs. alcohol paired with reinforcing feedback. Both groups rated categories of affective images (puppies, scenery, babies, neutral) similarly, but the hazardous drinking group rated alcohol significantly higher. There were no group differences in performance or in RewP amplitudes, even as a function of alcohol imagery. Contrary to prior findings, we did not observe a significant correlation between alcohol image rating and alcohol-specific RewP amplitude, although we did observe this relationship with the alcohol-specific delta band spectral representation of RewP. Within hazardous drinking group, there was significant correlation between hazardous drinking (AUDIT score) and alcohol-specific RewP indicating an inter-individual influence of drinking habits on affect specific RewP. These findings suggest a domain-specific enhancement of reward responsiveness in hazardous drinkers.

Immediate and lasting effects of different regulation of craving strategies on cue-induced craving and the late positive potential in smokers

Craving, induced by substance-related cues, contributes to continued substance use and relapse. Therefore, regulation of craving (ROC) is important for treatment success. Distraction involves disengaging from craving-inducing cues; whereas, reappraisal requires engaging with potential risks of substance use. Given this difference in elaboration, we addressed the question whether reappraisal entails lasting advantages over distraction in successful ROC. To elucidate how this is implemented neurally, we examined the late positive potential (LPP) as an electrocortical indicator of motivated attention to cues. N = 62 smokers viewed smoking-related pictures and indicated the degree of craving each picture induced. While viewing the pictures, EEG was recorded, and the participants focused on the long-term negative (LATER) or short-term positive (NOW) consequences of smoking or performed an arithmetic task to distract themselves from processing the pictures (DISTRACT). After a break, all pictures were presented again without regulation instruction (re-exposure). Results revealed that LATER and DISTRACT achieved similar degrees of immediate ROC success, but only LATER had a sustained effect during re-exposure. In contrast, LPP amplitudes were more prominently reduced during DISTRACT than LATER, and there was no difference in LPP amplitudes during re-exposure. These findings imply that it may be beneficial to engage with the risks of drug use (reappraisal) rather than avoiding triggers of craving (distraction). However, these effects do not seem to be mediated by lasting changes in cue-related motivated attention (LPP).

Neuroaffective reactivity profiles are associated with vulnerability to e-cigarette use

BACKGROUND

We tested whether neuroaffective responses to motivationally salient stimuli are associated with vulnerability to cue-induced e-cigarette use in e-cigarette naïve adults who smoke daily. We hypothesized that individuals with stronger neuroaffective responses to nicotine-related cues than to pleasant stimuli (the C>P reactivity profile) would be more vulnerable to cue-induced nicotine self-administration than individuals with stronger neuroaffective responses to pleasant stimuli than to nicotine-related cues (the P>C reactivity profile).

METHODS

We used event-related potentials (ERPs, a direct measure of cortical activity) to measure neuroaffective reactivity to pleasant, unpleasant, neutral, and nicotine-related cues indicating the opportunity to use an e-cigarette in 36 participants. For each picture category, we computed the amplitude of the late positive potential (LPP), a robust index of motivational salience. To identify each individual's neuroaffective reactivity profile we applied k-means cluster analysis on the LPP responses. We compared the e-cigarette use frequency across profiles using quantile regression for counts.

RESULTS

K-means cluster analysis assigned 18 participants to the C>P profile and 18 participants to the P>C profile. Individuals with the C>P neuroaffective profile used the e-cigarette significantly more often than those with the P>C profile. Significant differences in the number of puffs persisted across different quantiles.

CONCLUSIONS

These results support the hypothesis that individual differences in the tendency to attribute motivational salience to drug-related cues underlie vulnerability to cue-induced drug self-administration. Targeting the neuroaffective profiles that we identified with tailored treatments could improve clinical outcomes.

A Comparative Event-Related Potentials Study between Alcohol Use Disorder, Gambling Disorder and Healthy Control Subjects through a Contextual Go/NoGo Task

(1) Background: Inhibitory and rewarding processes that mediate attentional biases to addiction-related cues may slightly differ between patients suffering from alcohol use (AUD) or gambling (GD) disorder. (2) Methods: 23 AUD inpatients, 19 GD patients, and 22 healthy controls performed four separate Go/NoGo tasks, in, respectively, an alcohol, gambling, food, and neutral long-lasting cueing context during the recording of event-related potentials (ERPs). (3) Results: AUD patients showed a poorer inhibitory performance than controls (slower response latencies, lower N2d, and delayed P3d components). In addition, AUD patients showed a preserved inhibitory performance in the alcohol-related context (but a more disrupted one in the food-related context), while GD patients showed a specific inhibitory deficit in the game-related context, both indexed by N2d amplitude modulations. (4) Conclusions: Despite sharing common addiction-related mechanisms, AUD and GD patients showed different patterns of response to (non-)rewarding cues that should be taken into account in the therapeutic context.

A Bibliometric Analysis of Consumer Neuroscience towards Sustainable Consumption

Consumer neuroscience is a new paradigm for studying consumer behavior, focusing on neuroscientific tools to explore the underlying neural processes and behavioral implications of consumption. Based on the bibliometric analysis tools, this paper provides a review of progress in research on consumer neuroscience during 2000–2021. In this paper, we identify research hotspots and frontiers in the field through a statistical analysis of bibliometric indicators, including the number of publications, countries, institutions, and keywords. Aiming at facilitating carbon neutrality via sustainable consumption, this paper discusses the prospects of applying neuroscience to sustainable consumption. The results show 364 publications in the field during 2000–2021, showing a rapid upward trend, indicating that consumer neuroscience research is gaining ground. The majority of these consumer neuroscience studies chose to use electroencephalogram tools, accounting for 63.8% of the total publications; the cutting-edge research mainly involved event-related potential (ERP) studies of various marketing stimuli interventions, functional magnetic resonance imaging (fMRI)-based studies of consumer decision-making and emotion-specific brain regions, and machine-learning-based studies of consumer decision-making optimization models.

Correlation between abnormal brain network activity and electroencephalogram microstates on exposure to smoking-related cues

BACKGROUND

Research into neural mechanisms underlying cue-induced cigarette craving has attracted considerable attention for its significant role in treatments. However, there is little understanding about the effects of exposure to smoking-related cues on electroencephalogram (EEG) microstates of smokers, which can reflect abnormal brain network activity in several psychiatric disorders.

AIMS

To explore whether abnormal brain network activity in smokers on exposure to smoking-related cues would be captured by EEG microstates.

METHOD

Forty smokers were exposed to smoking and neutral imagery conditions (cues) during EEG recording. Behavioural data and parameters for microstate topographies associated with the auditory (A), visual (B), salience and memory (C) and dorsal attention networks (D) were compared between conditions. Correlations between microstate parameters and cigarette craving as well as nicotine addiction characteristics were also analysed.

RESULTS

The smoking condition elicited a significant increase in the duration of microstate classes B and C and in the duration and contribution of class D compared with the neutral condition. A significant positive correlation between the increased duration of class C (smoking minus neutral) and increased craving ratings was observed, which was fully mediated by increased posterior alpha power. The increased duration and contribution of class D were both positively correlated with years of smoking.

CONCLUSIONS

Our results indicate that smokers showed abnormal EEG microstates when exposed to smoking-related cues compared with neutral cues. Importantly, microstate class C (duration) might be a biomarker of cue-induced cigarette craving, and class D (duration and contribution) might reflect the relationship between cue-elicited activation of the dorsal attention network and years of smoking.

Acute sensitization of the P3 event-related potential response to beverage images and the risk for alcohol use disorder

Previous research suggests the amplitude of the P3 event-related potential (ERP) response reflects the incentive value of the eliciting stimulus, and that individuals with trait-like lower sensitivity (LS) to the acute effects of alcohol, a potent risk factor for alcohol use disorder (AUD), tend to show exaggerated P3 ERP responses to alcohol beverage cues (compared to their peers with higher sensitivity; HS). No prior research has examined trajectories of the cue-elicited P3 response across repeated trials of nonreinforced cue presentations. Characterizing these trajectories can be informative as to potential mechanisms linking LS with increased AUD risk. Here, we tested whether individual differences in alcohol sensitivity are associated with different trial-by-trial trajectories of the P3 elicited by alcohol and nonalcohol reward cues (infrequent oddball/target stimuli) using a large sample of emerging adults (M _age = 19.53; N = 287; 55% female; 86% White; 90% right-handed) stratified for alcohol sensitivity. Multilevel models adjusted for age, sex, handedness, and alcohol use indicated that: (i) the P3 response to alcohol and nonalcohol reward cues alike sensitized (i.e., increased) across trials; (ii) across the task, the P3 response to alcohol cues was larger for the LS than the HS phenotype; and (iii) the P3 difference score (alcohol - nonalcohol) was larger for the LS than HS phenotype only across the first half of task. Findings suggest that whereas incentive value attribution may be a mechanism for alcohol cue-triggered attentional biases for both LS and HS individuals, LS individuals more consistently over-attribute incentive value to alcohol cues.

Late positive potential as a candidate biomarker of motivational relevance in substance use: Evidence from a meta-analysis

The objective of the current meta-analysis was to assess the effect size of the Late Positive Potential (LPP) to drug and emotional cues in substance users compared to controls. The secondary objective was to test for moderation by: age, gender, years of use, use status, and substance type. Search was performed in August 2021 using PubMed. Inclusion criteria were: substance use disorder/dependence or validated self-report, LPP means, healthy control comparison, non-acute drug study, data available, peer-reviewed journal, English, and human participants. Selection bias was tested through modified Egger's regression and exploratory 3-parameter selection model tests. Results (k = 11) indicated LPP to drug cues was larger in substance use compared to control group, with a large effect size (Hedges' g=1.66, 95%CI [0.64,2.67], p = 0.005). There were no overall differences for emotional cues. Though threats of selection bias were not severe, inclusion of more studies with larger sample sizes in future meta-analyses will allow more robust tests of publication bias and more accurate measures of effect size.

An EEG study on the effect of being overweight on anticipatory and consummatory reward in response to pleasant taste stimuli

Two-thirds of adults in the United Kingdom currently suffer from overweight or obesity, making it one of the biggest contributors to health problems. Within the framework of the incentive sensitisation theory, it has been hypothesised that overweight people experience heightened reward anticipation when encountering cues that signal food, such as pictures and smells of food, but that they experience less reward from consuming food compared to normal-weight people. There is, however, little evidence for this prediction. Few studies test both anticipation and consumption in the same study, and even fewer with electroencephalography (EEG). This study sought to address this gap in the literature by measuring scalp activity when overweight and normal-weight people encountered cues signalling the imminent arrival of pleasant and neutral taste stimuli, and when they received these stimuli. The behavioural data showed that there was a smaller difference in valence ratings between the pleasant and neutral taste in the overweight than normal-weight group, in accordance with our hypothesis. However, contrary to our hypothesis, the groups did not differ in their electrophysiological response to taste stimuli. Instead, there was a reduction in N1 amplitude to both taste and picture cues in overweight relative to normal-weight participants. This suggests that reduced attention to cues may be a crucial factor in risk of overweight.

Effects of Transcranial Direct Current Stimulation on Attentional Bias to Methamphetamine Cues and Its Association With EEG-Derived Functional Brain Network Topology

BACKGROUND

Although transcranial direct current stimulation (tDCS) has shown to potentially mitigate drug craving and attentional bias to drug-related stimuli, individual differences in such modulatory effects of tDCS are less understood. In this study, we aimed to investigate a source of the inter-subject variability in the tDCS effects that can be useful for tDCS-based treatments of individuals with methamphetamine (MA) use disorder (IMUD).

METHODS

Forty-two IMUD (all male) were randomly assigned to receive a single-session of either sham or real bilateral tDCS (anodal right/cathodal left) over the dorsolateral prefrontal cortex. The tDCS effect on MA craving and biased attention to drug stimuli were investigated by quantifying EEG-derived P3 (a measure of initial attentional bias) and late positive potential (LPP; a measure of sustained motivated attention) elicited by these stimuli. To assess the association of changes in P3 and LPP with brain connectivity network (BCN) topology, the correlation between topology metrics, specifically those related to the efficiency of information processing, and the tDCS effect was investigated.

RESULTS

The P3 amplitude significantly decreased following the tDCS session, whereas the amplitudes increased in the sham group. The changes in P3 amplitudes were significantly correlated with communication efficiency measured by BCN topology metrics (r = -0.47, P = .03; r = -0.49, P = .02). There was no significant change in LPP amplitude due to the tDCS application.

CONCLUSIONS

These findings validate that tDCS mitigates initial attentional bias, but not the sustained motivated attention, to MA stimuli. Importantly, however, results also show that the individual differences in the effects of tDCS may be underpinned by communication efficiency of the BCN topology, and therefore, these BCN topology metrics may have the potential to robustly predict the effectiveness of tDCS-based interventions on MA craving and attentional bias to MA stimuli among IMUD.

Differential brain responses to alcohol-related and natural rewards are associated with alcohol use and problems: Evidence for reward dysregulation

Multiple theoretical perspectives posit that drug use leads to biased valuation of drug-related reward, at the expense of naturally occurring rewarding activities (i.e., reward dysregulation). Recent research suggests that the comparative balance of drug-related and nondrug-related reward valuation is a powerful determinant of substance misuse and addiction. We examined differential neurophysiological responses-indexed with the P3 component of the event-related potential (ERP)-elicited by visual alcohol cues and cues depicting natural reward as a neurobiological indicator of problematic drinking. Nondependent, young adult drinkers (N = 143, aged 18-30 years) completed questionnaire measures assessing alcohol use and problems, and viewed alcohol cues (pictures of alcoholic beverages), high-arousing natural reward cues (erotica, adventure scenes), nonalcoholic beverage cues, and neutral scenes (e.g., household items) while ERPs were recorded. When examined separately, associations of P3-ERP reactivity to alcohol cues and natural reward cues with alcohol use and problems were weak. However, differential P3 response to the two types of cues (i.e., reward dysregulation P3) showed consistent and robust associations with all indices of alcohol use and problems and differentiated high-risk from lower-risk drinkers. The current results support the idea that the differential incentive-motivational value of alcohol, relative to naturally rewarding activities, is associated with increased risk for substance misuse and dependence, and highlight a novel neurophysiological indicator-the reward dysregulation P3-of this differential reward valuation.

No smoking signs with strong smoking symbols induce weak cravings: an fMRI and EEG study

No smoking signs (NSSs) that combine smoking symbols (SSs) and prohibition symbols (PSs) represent common examples of reward and prohibition competition. To evaluate how SSs within NSSs influence their effectiveness in guiding reward vs. prohibition, we studied 93 male smokers. We collected self-reported craving ratings (N=30), cue reactivity under fMRI/EEG (N=33), and smoking-behavior anticipation for paired NSSs and SSs (N=30). We found that NSS-induced cravings were negatively correlated with SS-induced cravings and PS-induced inhibition. fMRI indicated that both correlations were mediated by activation of the inferior frontal gyrus and precuneus, suggesting that the effects of SSs and PSs interact with each other. EEG revealed that the prohibition response occurs after the cigarette response, indicating that the cigarette response might be precluded by the prohibition, supporting the effect of SSs in discouraging smoking. Moreover, stronger SSs induced stronger slow positive waves and late positive potentials, and the stronger the late positive potentials, the stronger the late positive potentials. Both the amplitudes of late positive potentials and slow positive waves were positively correlated with the amplitude of N2, which was positively correlated with the attention grabbed score by the NSS. In addition, the weaker the NSS-induced craving, the greater the smoking behavior anticipation reduction, indicating the capability of NSSs to decrease smoking behavior. Our study provides empirical evidence for selecting the most effective NSSs: those combining strong SS and PS, offering insights about competition between cigarette reward and prohibition and providing neural evidence on how cigarette reward and prohibition interact.

Internal consistency and test-retest reliability of the P3 event-related potential (ERP) elicited by alcoholic and non-alcoholic beverage pictures

Addiction researchers are interested in the ability of neural signals, like the P3 component of the ERP, to index individual differences in liability factors like motivational reactivity to alcohol/drug cues. The reliability of these measures directly impacts their ability to index individual differences, yet little attention has been paid to their psychometric properties. The present study fills this gap by examining within-session internal consistency reliability (ICR) and between-session test-retest reliability (TRR) of the P3 amplitude elicited by images of alcoholic beverages (Alcohol Cue P3) and non-alcoholic drinks (NADrink Cue P3) as well as the difference between them, which isolates alcohol cue-specific reactivity in the P3 (ACR-P3). Analyses drew on data from a large sample of alcohol-experienced emerging adults (session 1 N = 211, 55% female, aged 18-20 yr; session 2 N = 98, 66% female, aged 19-21 yr). Evaluated against domain-general thresholds, ICR was excellent (M ± SD; r= 0.902 ± 0.030) and TRR was fair (r = 0.706 ± 0.020) for Alcohol Cue P3 and NADrink Cue P3, whereas for ACR-P3, ICR and TRR were poor (r = 0.370 ± 0.071; r = 0.201 ± 0.042). These findings indicate that individual differences in the P3 elicited by cues for ingested liquid rewards are highly reliable and substantially stable over 8-10 months. Individual differences in alcohol cue-specific P3 reactivity were less reliable and less stable. The conditions under which alcohol/drug cue-specific reactivity in neural signals is adequately reliable and stable remain to be discovered.

Value-based cognition and drug dependency

Value-based decision-making is thought to play an important role in drug dependency. Achieving elevated levels of euphoria or ameliorating dysphoria/pain may motivate goal-directed drug consumption in both drug-naïve and long-time users. In other words, drugs become viewed as the preferred means of attaining a desired internal state. The bias towards choosing drugs may affect one's cognition. Observed biases in learning, attention and memory systems within the brain gradually focus one's cognitive functions towards drugs and related cues to the exclusion of other stimuli. In this narrative review, the effects of drug use on learning, attention and memory are discussed with a particular focus on changes across brain-wide functional networks and the subsequent impact on behaviour. These cognitive changes are then incorporated into the cycle of addiction, an established model outlining the transition from casual drug use to chronic dependency. If drug use results in the elevated salience of drugs and their cues, the studies highlighted in this review strongly suggest that this salience biases cognitive systems towards the motivated pursuit of addictive drugs. This bias is observed throughout the cycle of addiction, possibly contributing to the persistent hold that addictive drugs have over the dependent. Taken together, the excessive valuation of drugs as the preferred means of achieving a desired internal state affects more than just decision-making, but also learning, attentional and mnemonic systems. This eventually narrows the focus of one's thoughts towards the pursuit and consumption of addictive drugs.

Electrophysiological indexes for impaired response inhibition and salience attribution in substance (stimulants and depressants) use disorders: A meta-analysis

The impairment of inhibitory control and reward system is the core feature underlying substance use disorder (SUD). Previous studies suggested that it can be regarded as impaired response inhibition and salience attribution syndrome (iRISA). The neural substrates of the two deficit functions were widely investigated in neuroimaging studies, and the impaired prefrontal cortex, limbic-orbitofrontal network, and fronto-insular-parietal network were observed. Previous Event-related potential (ERP) studies were also conducted to explore EEG indexes related to abnormal brain function. In the current meta-analysis, we aimed to explore the consistency of ERP indexes that can reflect the two aberrant processes: P300/slow potential (SP) for salience attribution and Error-related negativity (ERN)/Nogo-N200/Nogo-P300 for inhibitory control and conflict monitoring. Subgroup analyses for drug type and drug use conditions were also conducted. According to the 60 research studies, we found significantly enhanced drug-cue-induced P300 amplitude and attenuated Nogo-N200 amplitude in SUD individuals relative to Healthy control (HC), which supports the dual model. Moreover, the drug-cue-induced P300 displayed time-dependence recovery, suggesting a potential index for treatment evaluation. In conclusion, drug-cue-induced P300 and Nogo-N200 demonstrated high consistency, and the drug-cue-induced P300 can be used to track the changes of functional recovery for SUD. The integration of the two ERP components could be regarded as a potential biomarker for SUD, which may provide a new insight for clinical treatment and investigation.

Repetitive transcranial magnetic stimulation as a potential treatment approach for cannabis use disorder

The expanding legalization of cannabis across the United States is associated with increases in cannabis use, and accordingly, an increase in the number and severity of individuals with cannabis use disorder (CUD). The lack of FDA-approved pharmacotherapies and modest efficacy of psychotherapeutic interventions means that many of those who seek treatment for CUD relapse within the first few months. Consequently, there is a pressing need for innovative, evidence-based treatment development for CUD. Preliminary evidence suggests that repetitive transcranial magnetic stimulation (rTMS) may be a novel, non-invasive therapeutic neuromodulation tool for the treatment of a variety of substance use disorders (SUDs), including recently receiving FDA clearance (August 2020) for use as a smoking cessation aid in tobacco cigarette smokers. However, the potential of rTMS for CUD has not yet been reviewed. This paper provides a primer on therapeutic neuromodulation techniques for SUDs, with a particular focus on reviewing the current status of rTMS research in people who use cannabis. Lastly, future directions are proposed for rTMS treatment development in CUD, with suggestions for study design parameters and clinical endpoints based on current gold-standard practices for therapeutic neuromodulation research.

A Novel Cognition-Guided Neurofeedback BCI Dataset on Nicotine Addiction

Compared with the traditional neurofeedback paradigm, the cognition-guided neurofeedback brain–computer interface (BCI) is a novel paradigm with significant effect on nicotine addiction. However, the cognition-guided neurofeedback BCI dataset is extremely lacking at present. This paper provides a BCI dataset based on a novel cognition-guided neurofeedback on nicotine addiction. Twenty-eight participants are recruited and involved in two visits of neurofeedback training. This cognition-guided neurofeedback includes two phases: an offline classifier construction and a real-time neurofeedback training. The original electroencephalogram (EEG) raw data of two phases are provided and evaluated in this paper. The event-related potential (ERP) amplitude and channel waveform suggest that our BCI dataset is of good quality and consistency. During neurofeedback training, the participants’ smoking cue reactivity patterns have a significant reduction. The mean accuracy of the multivariate pattern analysis (MVPA) classifier can reach approximately 70%. This novel cognition-guided neurofeedback BCI dataset can be used to develop comparisons with other neurofeedback systems and provide a reference for the development of other BCI algorithms and neurofeedback paradigms on addiction.

Motivated attention to stimuli related to social networking sites: A cue-reactivity study

BACKGROUND AND AIMS

It has been argued that similar to addictive behaviors, problematic Social Network sites use (PSNSU) is characterized by sensitized reward processing and cue-reactivity. However, no study to our knowledge has yet investigated cue-reactivity in PSNSU. The present study aims at investigating cue-reactivity to Social Network sites (i.e., Facebook)-related visual cues in individuals identified as problematic vs. non-problematic Facebook users by the Problematic Facebook Use Scale.

METHODS

The Event-Related Potentials (ERPs) were recorded during the passive viewing of Facebook-related, pleasant, unpleasant, and neutral pictures in 27 problematic and 26 non-problematic users. Moreover, craving for Facebook usage was collected using a Likert scale.

RESULTS

Despite problematic users were more likely to endorse higher craving than non-problematic ones, Facebook-related cues elicited larger ERP positivity (400-600 ms) than neutral, and comparable to unpleasant stimuli, in all Facebook users. Only in problematic users we found larger positivity (600-800 ms) to pleasant than unpleasant cues and higher craving to be related with lower later positivity (800-1,000 ms) to pleasant and unpleasant cues.

DISCUSSION

Regardless of whether Facebook usage is problematic or non-problematic, Facebook-related cues seem to be motivationally relevant stimuli that capture attentional resources in the earlier stages of "motivated" attentional allocation. Moreover, our results support the view that in higher-craving problematic users, reduced abilities to experience emotions would be the result of defective emotion regulation processes that allow craving states to capture more motivational/attentional resources at the expense of other emotional states.

Attention bias modification in drug addiction: Enhancing control of subsequent habits

A relapse in addiction is often precipitated by heightened attention bias to drug-related cues, underpinned by a subcortically mediated transition to habitual/automatized responding and reduced prefrontal control. Modification of such automatized attention bias is a fundamental, albeit elusive, target for relapse reduction. Here, on a trial-by-trial basis, we used electroencephalography and eye tracking with a task that assessed, in this order, drug cue reactivity, its instructed self-regulation via reappraisal, and the immediate aftereffects on spontaneous (i.e., not instructed and automatized) attention bias. The results show that cognitive reappraisal, a facet of prefrontal control, decreased spontaneous attention bias to drug-related cues in cocaine-addicted individuals, more so in those with less frequent recent use. The results point to the mechanisms underlying the disruption of automatized maladaptive drug-related attention bias in cocaine addiction. These results pave the way for future studies to examine the role of such habit disruption in reducing compulsive drug seeking outside the controlled laboratory environment, with the ultimate goal of developing a readily deployable cognitive-behavioral and personalized intervention for drug addiction.

A Systematic Review of Electrophysiological Findings in Binge-Purge Eating Disorders: A Window Into Brain Dynamics

Binge-purge eating disorders (BP-ED), such as bulimia nervosa and binge eating disorder, may share some neurobiological features. Electroencephalography (EEG) is a non-invasive measurement modality that may aid in research and diagnosis of BP-ED. We conducted a systematic review of the literature on EEG findings in BP-ED, seeking to summarize and analyze the current evidence, as well as identify shortcomings and gaps to inform new perspectives for future studies. Following PRISMA Statement recommendations, the PubMed, Embase, and Web of Science databases were searched using terms related to “electroencephalography” and “binge-purge” eating disorders. Of 555 articles retrieved, 15 met predefined inclusion criteria and were included for full-text analysis. Eleven studies investigated EEG by means of event-related potentials (ERP) in BP-ED individuals: 7 using eating disorder-related stimuli (i.e., food, body image) and 4 using non-eating disorder-related stimuli (i.e., facial expressions or auditory clicks). These studies found significant differences in the N200, P200, P300, and LPP components in BP-ED participants compared to controls, indicating that this population exhibits impairments in selective attention, attentional allocation/processing, and allocation of motivational or emotion-based attention. Five studies investigated EEG using frequency analysis; reporting significant differences in beta activity in fronto-temporal and occipito-temporo-parietal areas in BP-ED individuals compared to controls, revealing a dysfunctional brain network. However, the small number of studies, the heterogeneity of samples, study paradigms, stimulus types, and the lack of an adequate assessment of neuropsychological parameters are some limitations of the current literature. Although some EEG data are promising and consistent with neuroimaging and neuropsychological findings in individuals with BP-ED, future studies need to overcome current methodological shortcomings.

Electrocortical correlates of impaired motor inhibition and outcome processing are related in high binge-watching

Models posit problematic binge-watching to involve a vicious circle of low motivation for alternative activities, low sensitivity for the consequences of neglected goals, and low self-control. As such, simultaneously impaired feedback and inhibitory functioning might contribute to binge-watching. We tested the hypothesis that blunted feedback-related brain activity is coupled with attenuated inhibitory brain activity in binge-watchers. High (n = 32) and non-binge-watchers (n = 31) performed go/nogo (inhibition) and stop signal (stopping) tasks and a flanker paradigm with performance feedback during electroencephalography. We examined how neural correlates of inhibition and stopping were associated with outcome processing in each group. We assessed the temporospatial relationship using a single-trial regression approach. High binge-watchers, but not non-binge-watchers, who differentiated less between gains and losses at the neural level (feedback-P3b) also recruited less brain activity during both inhibition and stopping (inhibition-P3 and stopping-P3). Exploratory analyses suggested that these relationships were most prominent in high binge-watchers with high loss of control over watching. Main effects of the group in performance or EEG did not emerge. These results suggest a potentially problematic interaction between outcome and inhibitory functions in binge-watchers. Insensitivity to behavioral consequences along with inhibitory impairments may also confer a long-term risk for compulsive watching. Our multi-modal approach may be particularly suited to detect such an underlying risk marker.

Incentive sensitization in binge behaviors: A mini review on electrophysiological evidence

Introduction

Binge behavior not only refers to the consumption of substances such as alcohol or food, but is also used in relation to gaming, watching and gambling. Dependent on context it makes for a widespread, benign recreational activity or can pose a serious mental health problem with deleterious consequences. Incentive sensitization theory describes the attribution of salience towards stimuli strongly associated with dopamine-mediated reward as a result of repeated consumption. The sensitized neural networks cause cue-triggered craving and excessive desire, but thus, this mechanism may also be applicable to stimulus-induced behaviors not associated with classical withdrawal symptoms. Event-related potentials (ERP) are a useful method of examining motivated attention towards incentive stimuli. This mini review aims to synthesize ERP findings from different types of binge behaviors in order to compare cue-reactivity to incentive stimuli.

Methods

Studies investigating binge drinking, binge eating as well as binge watching, gaming and gambling were screened. To limit the influence of concurrent task demands, ERP studies applying picture viewing paradigms with incentive stimuli were selected.

Results

Across binge behaviors, evidence on altered mid-latency ERPs has been mixed. However, studies investigating later stages of attentional processes more consistently find enlarged P300 and late positive potentials (LPP) amplitudes to relevant cues.

Conclusion

An altered attentional processing of incentive stimuli reflecting motivated attention is in line with incentive sensitization theory. Considering the limited number of studies, especially regarding binge behaviors not involving substances, more research is needed to attain a more thorough understanding of incentive sensitization across binge behaviors.

Mood-induced changes in the cortical processing of food images in bulimia nervosa

BACKGROUND

Negative mood often triggers binge eating in bulimia nervosa (BN). We investigated motivational salience as a possible underlying mechanism using event-related potentials (ERPs) as indicators of motivated attention allocation (P300) and sustained processing (LPP).

METHODS

We collected ERPs (P300: 350-400 ms; LPP: 600-1000 ms) from 21 women with full-syndrome or partially remitted BN and 21 healthy women (HC), matched for age and body mass index. Idiosyncratic negative and neutral situations were used to induce corresponding mood states (counterbalanced), before participants viewed images of high- and low-calorie foods and neutral objects, and provided ratings for pleasantness and desire to eat.

RESULTS

P300 was larger for foods than objects; LPP was largest for high-calorie foods, followed by low-calorie foods, then objects. The BN group showed an increased desire to eat high-calorie foods under negative mood and stronger mood induction effects on ERPs than the HC group, with generally reduced P300 and a small increase in LPP for high-calorie foods. Effects were limited to circumscribed electrode positions. Exploratory analyses showed clearer effects when comparing high vs. low emotional eaters.

CONCLUSION

We argue that negative mood decreased the availability of cognitive resources (decreased P300) in BN, thereby facilitating disinhibition and food cravings (increased desire-to-eat ratings). Increased sustained processing might be linked to emotional eating tendencies rather than BN pathology per se, and reflect approach motivation, conflict, or regulatory processes. Negative mood appears to induce complex changes in food image processing, whose understanding may contribute to the development of tailored interventions in the future.

General and specific graphic health warning labels reduce willingness to consume sugar-sweetened beverages

Sugar-sweetened beverage (SSB) consumption is associated with obesity and other severe negative health consequences. The present study examined the effectiveness of two types of health warning labels (HWLs) in modulating dietary choices for SSBs: specific HWLs, presenting health consequences associated with consuming SSBs, and general HWLs, presenting health consequences of an unhealthy diet and obesity. While electroencephalography (EEG) was recorded, 63 participants completed a computer-based task in which they were first randomly allocated to view either SBB-specific, general, or non-warning control HWLs. They then viewed images of a range of SSB products, varying on perceived healthiness and tastiness, and rated their willingness to consume (WTC) each one. Linear mixed-effect model analyses revealed that general and specific HWLs both decreased WTC SSBs perceived as tasty, compared to the control condition. For general HWLs, this effect was reduced for SSBs perceived to be healthy, suggesting that specific HWLs may be more effective at reducing SSB consumption. The EEG data showed that SSBs considered unhealthy elicited greater N1 amplitudes, and tasty SSBs elicited greater late positive potential (LPP) amplitudes, possibly reflecting attentional allocation and craving responses, respectively. However, no strong differences between HWL types were found. Taken together, the results suggest that graphic HWLs, both general and specific, have the potential to reduce SSB consumption, but they do not strongly modulate craving-related neural responses to SSBs.

Special Report on the Impact of the COVID-19 Pandemic on Clinical EEG and Research and Consensus Recommendations for the Safe Use of EEG

INTRODUCTION

The global COVID-19 pandemic has affected the economy, daily life, and mental/physical health. The latter includes the use of electroencephalography (EEG) in clinical practice and research. We report a survey of the impact of COVID-19 on the use of clinical EEG in practice and research in several countries, and the recommendations of an international panel of experts for the safe application of EEG during and after this pandemic.

METHODS

Fifteen clinicians from 8 different countries and 25 researchers from 13 different countries reported the impact of COVID-19 on their EEG activities, the procedures implemented in response to the COVID-19 pandemic, and precautions planned or already implemented during the reopening of EEG activities.

RESULTS

Of the 15 clinical centers responding, 11 reported a total stoppage of all EEG activities, while 4 reduced the number of tests per day. In research settings, all 25 laboratories reported a complete stoppage of activity, with 7 laboratories reopening to some extent since initial closure. In both settings, recommended precautions for restarting or continuing EEG recording included strict hygienic rules, social distance, and assessment for infection symptoms among staff and patients/participants.

CONCLUSIONS

The COVID-19 pandemic interfered with the use of EEG recordings in clinical practice and even more in clinical research. We suggest updated best practices to allow safe EEG recordings in both research and clinical settings. The continued use of EEG is important in those with psychiatric diseases, particularly in times of social alarm such as the COVID-19 pandemic.

Toward Precision Medicine for Smoking Cessation: Developing a Neuroimaging-Based Classification Algorithm to Identify Smokers at Higher Risk for Relapse

INTRODUCTION

By improving our understanding of the neurobiological mechanisms underlying addiction, neuroimaging research is helping to identify new targets for personalized treatment interventions. When trying to quit, smokers with larger electrophysiological responses to cigarette-related, compared with pleasant, stimuli ("C > P") are more likely to relapse than smokers with the opposite brain reactivity profile ("P > C").

AIM AND METHOD

The goal was to (1) build a classification algorithm to identify smokers characterized by P > C or C > P neuroaffective profiles and (2) validate the algorithm's classification outcomes in an independent data set where we assessed both smokers' electrophysiological responses at baseline and smoking abstinence during a quit attempt. We built the classification algorithm applying discriminant function analysis on the event-related potentials evoked by emotional images in 180 smokers.

RESULTS

The predictive validity of the classifier showed promise in an independent data set that included new data from 177 smokers interested in quitting; the algorithm classified 111 smokers as P > C and 66 as C > P. The overall abstinence rate was low; 15 individuals (8.5% of the sample) achieved CO-verified 12-month abstinence. Although individuals classified as P > C were nearly 2.5 times more likely to be abstinent than smokers classified as C > P (12 vs. 3, or 11% vs. 4.5%), this result was nonsignificant, preliminary, and in need of confirmation in larger trials.

CONCLUSION

These results suggest that psychophysiological techniques have the potential to advance our knowledge of the neurobiological underpinnings of nicotine addiction and improve clinical applications. However, larger sample sizes are necessary to reliably assess the predictive ability of our algorithm.

IMPLICATIONS

We assessed the clinical relevance of a neuroimaging-based classification algorithm on an independent sample of smokers enrolled in a smoking cessation trial and found those with the tendency to attribute more relevance to rewards than cues were nearly 2.5 times more likely to be abstinent than smokers with the opposite brain reactivity profile (11% vs. 4.5%). Although this result was not statistically significant, it suggests our neuroimaging-based classification algorithm can potentially contribute to the development of new precision medicine interventions aimed at treating substance use disorders. Regardless, these findings are still preliminary and in need of confirmation in larger trials.

Event-related potentials in a two-choice oddball task of impaired behavioral inhibitory control among males with tendencies towards cybersex addiction

BACKGROUND AND AIMS

Impaired behavioral inhibitory control (BIC) is known to play a crucial role in addictive behavior. However, research has been inconclusive as to whether this is also the case for cybersex addiction. This study aimed to investigate the time course of BIC in male individuals with tendencies towards cybersex addiction (TCA) using event-related potentials (ERPs) and to provide neurophysiological evidence of their deficient BIC.

METHODS

Thirty-six individuals with TCA and 36 healthy controls (HCs) were given a Two-Choice Oddball task that required them to respond differently to frequent standard stimuli (images of people) and infrequent deviant stimuli (pornographic images) within 1,000 ms. Electroencephalography (EEG) was recorded as the participants performed the task.

RESULTS

Despite the similarity of standard stimuli between the groups in terms of reaction times (RTs), the RTs of the TCA group to deviant stimuli were much slower than those of the HC group. The behavioral difference was accompanied by group differences in the averaged amplitudes of N2 (200-300 ms) and P3 (300-500 ms) components in the deviant-standard difference wave. More specifically, compared to the HC group, the TCA group demonstrated smaller N2 and P3 amplitude differences for deviant than standard stimuli.

DISCUSSION AND CONCLUSIONS

Individuals with TCA were more impulsive than HC participants and shared neuropsychological and ERP characteristics of substance use disorder or behavioral addictions, which supports the view that cybersex addiction can be conceptualized as a behavioral addiction.

Food-related attentional bias and its associations with appetitive motivation and body weight: A systematic review and meta-analysis

Theoretical models suggest that food-related visual attentional bias (AB) may be related to appetitive motivational states and individual differences in body weight; however, findings in this area are equivocal. We conducted a systematic review and series of meta-analyses to determine if there is a positive association between food-related AB and: (1.) body mass index (BMI) (number of effect sizes (k) = 110), (2.) hunger (k = 98), (3.) subjective craving for food (k = 35), and (4.) food intake (k = 44). Food-related AB was robustly associated with craving (r = 0.134 (95% CI 0.061, 0.208); p < .001), food intake (r = 0.085 (95% CI 0.038, 0.132); p < .001), and hunger (r = 0.048 (95% CI 0.016, 0.079); p = .003), but these correlations were small. Food-related AB was unrelated to BMI (r = 0.008 (95% CI -0.020, 0.035); p = .583) and this result was not moderated by type of food stimuli, method of AB assessment, or the subcomponent of AB that was examined. Furthermore, in a between-groups analysis (k = 22) which directly compared participants with overweight/obesity to healthy-weight control groups, there was no evidence for an effect of weight status on food-related AB (Hedge's g = 0.104, (95% CI -0.050, 0.258); p = .186). Taken together, these findings suggest that food-related AB is sensitive to changes in the motivational value of food, but is unrelated to individual differences in body weight. Our findings question the traditional view of AB as a trait-like index of preoccupation with food and have implications for novel theoretical perspectives on the role of food AB in appetite control and obesity.

Examining differences in attentional bias to smoking-related cues among black and white cigarette smokers: An event-related potential pilot study

Black cigarette smokers experience higher craving, lower cessation rates, and increased health complications from tobacco use than Whites. We examined psychophysiological and behavioral differences in attentional bias to smoking cues between Black and White smokers. Thirty-one participants (Blacks, n = 20; MAge = 45 and Whites, n = 11, MAge = 47.64) discriminated line orientations while ignoring temporally flanking lines and smoking-related, positive-, negative-, and neutral-images as behavioral responses and event-related potentials (ERPs) were recorded. Results revealed a three-way interaction in reaction time among Group (White, Black), Congruity (congruent vs. incongruent flankers) and Cue (smoking-related, positive, negative) factors, F(2,58) = 3.63, p = .03, MSe = .001, η2 = .002. Smoking-related cues yielded the largest congruity effects in Whites, but the smallest congruity effects in Blacks. Random presentation of smoking-related cues (re: baseline) weakened P1 ERP amplitude (125 ms after stimulus onset) in Whites, but not Blacks (Cue x Group x Task, F(3,87) = 3.44, p < .05, MSe = 65.96, η2 = .01), suggesting an early sensory effect of smoking cues in Whites. The difference between Whites and Blacks in P2 amplitude (226 ms; amplitude weaker in Whites) was greatest to the smoking-related cues (Cue x Group, F(3,87) = 2.81, p < .05, MSe = 60.68, η2 = .01), indicating a stronger draw in attention from smoking cues in Whites. Findings suggest White and Black smokers respond differently to smoking-related cues during early sensory processing. Findings need to be replicated.

Event-related potentials in a two-choice oddball task of impaired behavioral inhibitory control among males with tendencies towards cybersex addiction

BACKGROUND AND AIMS

Impaired behavioral inhibitory control (BIC) is known to play a crucial role in addictive behavior. However, research has been inconclusive as to whether this is also the case for cybersex addiction. This study aimed to investigate the time course of BIC in male individuals with tendencies towards cybersex addiction (TCA) using event-related potentials (ERPs) and to provide neurophysiological evidence of their deficient BIC.

METHODS

Thirty-six individuals with TCA and 36 healthy controls (HCs) were given a Two-Choice Oddball task that required them to respond differently to frequent standard stimuli (images of people) and infrequent deviant stimuli (pornographic images) within 1,000 ms. Electroencephalography (EEG) was recorded as the participants performed the task.

RESULTS

Despite the similarity of standard stimuli between the groups in terms of reaction times (RTs), the RTs of the TCA group to deviant stimuli were much slower than those of the HC group. The behavioral difference was accompanied by group differences in the averaged amplitudes of N2 (200-300 ms) and P3 (300-500 ms) components in the deviant-standard difference wave. More specifically, compared to the HC group, the TCA group demonstrated smaller N2 and P3 amplitude differences for deviant than standard stimuli.

DISCUSSION AND CONCLUSIONS

Individuals with TCA were more impulsive than HC participants and shared neuropsychological and ERP characteristics of substance use disorder or behavioral addictions, which supports the view that cybersex addiction can be conceptualized as a behavioral addiction.

Feel Safe and Money is Less Important! Hypnotic Suggestions of Safety Decrease Brain Responses to Monetary Rewards in a Risk Game

When a stimulus is important, the corresponding brain responses increase, especially the P300 brain response. This is true for all kinds of important stimuli, also monetary rewards. In our study, we developed a hypnotic suggestion to reduce the subjective importance of monetary rewards. As successful suggestions do not contain negations, we suggested participants to feel safe during hypnosis instead of suggesting that money is not important anymore. We predicted lower P300 amplitudes when participants feel safe during hypnosis. We tested 24 highly suggestible participants playing a risk game in 2 conditions with monetary rewards while we measured their EEG brain responses. In the safety condition, we induced a hypnotic state and suggested that participants feel safe. In the control condition, participants played the risk game without hypnosis. Here we show that participants felt significantly safer in the safety condition and showed significantly lower P300 amplitudes to monetary rewards. Risk behavior did not differ significantly between conditions. Our results are important for substance use disorders, as decreased P300 responses to substance-related stimuli are associated with less craving and better abstinence. Therefore, we conclude that suggestions to feel safe during hypnosis might work as a treatment for individuals with substance use disorders.

Effects of environmental tobacco smoke exposure on brain functioning in never-smoking adolescents

INTRODUCTION

Brain functioning, as indexed by event-related potentials (ERPs) representing smoking cue reactivity, inhibitory control, and reward processing, has been found to be compromised in smokers. However, whether environmental tobacco smoke (ETS) exposure in never smokers results in similar brain changes is unknown. This question is particularly relevant during adolescence, given ongoing brain maturation and a high risk of smoking initiation. The present study tested the associations between ETS exposure and ERPs reflecting cue reactivity (P3, LPP), inhibitory control (N2, P3), and reward processing (anticipation P3 (P3), feedback-related negativity (FRN)) among never-smoking adolescents.

METHODS

Eighty-four never-smoking adolescents (nonexposed = 32, exposed = 52) performed a smoking cue reactivity, a Go/NoGo, and a monetary incentive delay (MID) task while ERPs were measured.

RESULTS

Exposed and nonexposed groups did not differ in ERPs reflecting smoking cue reactivity, inhibitory control, and reward processing. A negative correlation between ETS exposure and the anticipatory P3 suggests reduced anticipatory reward sensitivity for nondrug rewards with increased levels of ETS exposure. However, since this effect was not consistent across analyses, no strong conclusions can be formulated. In the current study, few participants reported high levels of ETS exposure; therefore, further study is necessary.

CONCLUSIONS

Nevertheless, from this study, it can be concluded that low-to-moderate exposure to ETS during adolescence does not result in functional brain changes related to smoking cue reactivity, inhibitory control, and reward processing.

Dynamic functional connectivity between nucleus accumbens and the central executive network relates to chronic cannabis use

The neural mechanisms of drug cue‐reactivity regarding the temporal fluctuations of functional connectivity, namely the dynamic connectivity, are sparsely studied. Quantifying the task‐modulated variability in dynamic functional connectivity at cue exposure can aid the understanding. We analyzed changes in dynamic connectivity in 54 adult cannabis users and 90 controls during a cannabis cue exposure task. The variability was measured as standard deviation in the (a) connectivity weights of the default mode, the central executive, and the salience networks and two reward loci (amygdalae and nuclei accumbens); and (b) topological indexes of the whole brain (global efficiency, modularity and network resilience). These were compared for the main effects of task conditions and the group (users vs. controls), and correlated with pre‐ and during‐scan subjective craving. The variability of connectivity weights between the central executive network and nuclei accumbens was increased in users throughout the cue exposure task, and, was positively correlated with during‐scan craving for cannabis. The variability of modularity was not different by groups, but positively correlated with prescan craving. The variability of dynamic connectivity during cannabis cue exposure task between the central executive network and the nuclei accumbens, and, the level of modularity, seem to relate to the neural underpinning of cannabis use and the subjective craving.

Event-related and readiness potentials when preparing to approach and avoid alcohol cues following cue avoidance training in heavy drinkers

RATIONALE

Cue avoidance training (CAT) reduces alcohol consumption in the laboratory. However, the neural mechanisms that underlie the effects of this intervention are poorly understood.

OBJECTIVES

The present study investigated the effects of a single session of CAT on event-related and readiness potentials during preparation of approach and avoidance movements to alcohol cues.

METHODS

Heavy drinking young adults (N = 60) were randomly assigned to complete either CAT or control training. After training, we recorded participants' event-related and motor readiness potentials as they were preparing to respond.

RESULTS

In the CAT group, N200 amplitude was higher when preparing to approach rather than avoid alcohol pictures. In the control group, N200 amplitudes did not differ for approach and avoidance to alcohol pictures. Regarding the late positive potential (LPP), in the CAT group, the negativity of this was blunted when preparing to avoid alcohol pictures relative to when preparing to avoid control pictures. In the control group, the negativity of the LPP was blunted when preparing to approach alcohol pictures relative to when preparing to approach control pictures. There were no effects on motor readiness potentials. Behavioural effects indicated short-lived effects of training on reaction times during the training block that did not persist when participants were given time to prepare their motor response before executing it during the EEG testing block.

CONCLUSIONS

After a single session of CAT, the enhanced N200 when approaching alcohol cues may indicate the engagement of executive control to overcome the associations learned during training. These findings clarify the neural mechanisms that may underlie the effects of CAT on drinking behaviour.

Effect of deactivation of activity patterns related to smoking cue reactivity on nicotine addiction

With approximately 75% of smokers resuming cigarette smoking after using the Gold Standard Programme for smoking cessation, investigation into novel therapeutic approaches is warranted. Typically, smoking cue reactivity is crucial for smoking behaviour. Here we developed a novel closed-loop, smoking cue reactivity patterns EEG-based neurofeedback protocol and evaluated its therapeutic efficacy on nicotine addiction. During an evoked smoking cue reactivity task participants' brain activity patterns corresponding to smoking cues were obtained with multivariate pattern analysis of all EEG channels data, then during neurofeedback the EEG activity patterns of smoking cue reactivity were continuously deactivated with adaptive closed-loop training. In a double-blind, placebo-controlled, randomized clinical trial, 60 nicotine-dependent participants were assigned to receive two neurofeedback training sessions (∼1 h/session) either from their own brain (n = 30, real-feedback group) or from the brain activity pattern of a matched participant (n = 30, yoked-feedback group). Cigarette craving and craving-related P300 were assessed at pre-neurofeedback and post-neurofeedback. The number of cigarettes smoked per day was assessed at baseline, 1 week, 1 month, and 4 months following the final neurofeedback visit. In the real-feedback group, participants successfully deactivated EEG activity patterns of smoking cue reactivity. The real-feedback group showed significant decrease in cigarette craving and craving-related P300 amplitudes compared with the yoked-feedback group. The rates of cigarettes smoked per day at 1 week, 1 month and 4 months follow-up decreased 30.6%, 38.2%, and 27.4% relative to baseline in the real-feedback group, compared to decreases of 14.0%, 13.7%, and 5.9% in the yoked-feedback group. The neurofeedback effects on craving change and smoking amount at the 4-month follow-up were further predicted by neural markers at pre-neurofeedback. This novel neurofeedback training approach produced significant short-term and long-term effects on cigarette craving and smoking behaviour, suggesting the neurofeedback protocol described herein is a promising brain-based tool for treating addiction.

Decreases in the Late Positive Potential to Alcohol Images Among Alcohol Treatment Seekers Following Mindfulness-Based Relapse Prevention

Aim

Heightened craving among individuals with alcohol use disorder (AUD) has been attributed to a hypersensitivity to alcohol cues in attentional brain networks. Active mindfulness training has been shown to help improve attentional control. Here, we examined alcohol cue-related hypersensitivity among individuals with AUD who received rolling group mindfulness-based relapse prevention (MBRP) in combination with transcranial direct current stimulation (tDCS), over right inferior frontal gyrus.

Methods

Participants (n = 68) viewed a series of emotionally negative, emotionally neutral and alcohol-related images. Following image presentation, participants were asked to rate their level of craving for the alcohol cues, and their level of negative affect evoked by neutral and negative cues. During the task, electroencephalogram (EEG) was recorded to capture an event-related component shown to relate to emotionally salient stimuli: the late positive potential (LPP). Participants who completed a follow-up EEG (n = 37) performed the task a second time after up to eight sessions of MBRP coupled with active or sham tDCS.

Results

We found that both craving ratings and the LPP significantly decreased in response to alcohol cues from pre- to post-treatment, but not for other image cues. The magnitude of alcohol image craving reductions was associated with the number of MBRP group sessions attended. Active tDCS was not associated with craving ratings, but it was associated with greater LPP amplitudes across image types.

Conclusions

Taken together, these results suggest that disruption of alcohol-cue hypersensitivity in people with AUD may be a target mechanism of MBRP.

Evidence for incentive salience sensitization as a pathway to alcohol use disorder

The incentive salience sensitization (ISS) theory of addiction holds that addictive behavior stems from the ability of drugs to progressively sensitize the brain circuitry that mediates attribution of incentive salience (IS) to reward-predictive cues and its behavioral manifestations. In this article, we establish the plausibility of ISS as an etiological pathway to alcohol use disorder (AUD). We provide a comprehensive and critical review of evidence for: (1) the ability of alcohol to sensitize the brain circuitry of IS attribution and expression; and (2) attribution of IS to alcohol-predictive cues and its sensitization in humans and non-human animals. We point out gaps in the literature and how these might be addressed. We also highlight how individuals with different alcohol subjective response phenotypes may differ in susceptibility to ISS as a pathway to AUD. Finally, we discuss important implications of this neuropsychological mechanism in AUD for psychological and pharmacological interventions attempting to attenuate alcohol craving and cue reactivity.

Mindfulness-Oriented Recovery Enhancement remediates hedonic dysregulation in opioid users: Neural and affective evidence of target engagement

Addiction neuroscience models posit that recurrent drug use increases reactivity to drug-related cues and blunts responsiveness to natural rewards, propelling a cycle of hedonic dysregulation that drives addictive behavior. Here, we assessed whether a cognitive intervention for addiction, Mindfulness-Oriented Recovery Enhancement (MORE), could restructure reward responsiveness from valuation of drug-related reward back to valuation of natural reward. Before and after 8 weeks of MORE or a support group control, prescription opioid users (N = 135) viewed opioid and natural reward cues while an electroencephalogram biomarker of target engagement was assessed. MORE was associated with decreased opioid cue-reactivity and enhanced capacity to regulate responses to opioid and natural reward cues. Increased positive affective responses to natural reward cues were associated with decreased craving and mediated MORE's therapeutic effects on opioid misuse. This series of randomized experiments provide the first neurophysiological evidence that an integrative behavioral treatment can remediate hedonic dysregulation among chronic opioid users.

Neural mechanisms of affective instability and cognitive control in substance use

OBJECTIVE

We explored the impact of affect on cognitive control as this relates to individual differences in affective instability and substance use. Toward this end, we examined how different dimensions of affective instability interact to predict substance misuse and the effect of this on two event-related potential components, the reward positivity and the late positive potential, which are said to reflect the neural mechanisms of reward and emotion processing, respectively.

METHODS

We recorded the ongoing electroencephalogram from undergraduate students as they navigated two T-maze tasks in search of rewards. One of the tasks included neutral, pleasant, and unpleasant pictures from the International Affective Picture System. Participants also completed several questionnaires pertaining to substance use and personality.

RESULTS

A principal components analysis revealed a factor related to affective instability, which we named reactivity. This factor significantly predicted increased substance use. Individuals reporting higher levels of affective reactivity also displayed a larger reward positivity following stimuli with emotional content.

CONCLUSION

The current study uncovered a group of high-risk substance users who were characterized by greater levels of affective reactivity and context-specific increased sensitivity to rewards.

SIGNIFICANCE

These results help to elucidate the complex factors underlying substance use and may facilitate the creation of individually-tailored treatment programs for those struggling with substance use disorders.

Interactive Effects of Naturalistic Drinking Context and Alcohol Sensitivity on Neural Alcohol Cue-Reactivity Responses

BACKGROUND

Considerable evidence indicates that a low level of subjective response to alcohol's acute effects (i.e., low sensitivity) is associated with enhanced risk for alcohol use disorder (AUD). Recent work suggests that the highest risk response profile consists of blunted sensitivity to alcohol's sedation-like effects, coupled with enhanced sensitivity to alcohol's stimulation-like effects (i.e., differential sensitivity). A largely separate body of work indicates that enhanced reactivity to alcohol-related cues is associated with increased AUD risk.

AIMS

The current research examined the extent to which variability in alcohol response phenotypes is associated with enhanced P3 event-related potential (ERP) responses to alcohol-related pictures (ACR-P3), and whether this reactivity varies according to depicted drinking contexts.

METHODS

Eighty young adults (aged 18 to 33 years) completed a self-report measure of alcohol sensitivity (the Alcohol Sensitivity Questionnaire) and viewed images depicting drinking in naturalistic contexts, alcohol and nonalcohol beverages in isolation (devoid of naturalistic drinking context), and neutral nonbeverage control images while ERPs were recorded.

RESULTS

Results indicated that blunted sensitivity to alcohol's sedative-like effects was differentially associated with enhanced ACR-P3 but reduced P3 reactivity to nonalcohol cues. Variation in sensitivity to alcohol's stimulant-like effects was not associated with differential ACR-P3. Contrary to predictions, these effects were not potentiated by drinking contexts.

CONCLUSIONS

The current results replicate and extend previous work linking low alcohol sensitivity with enhanced incentive salience for alcohol-related cues and suggest that cues depicting drinking contexts are less likely to differentiate high-risk from low-risk drinkers.