The role of context in the processing of alcohol-relevant cues

Analysis of addiction craving onset through natural language processing of the online forum Reddit

AIMS

Alcohol cravings are considered a major factor in relapse among individuals with alcohol use disorder (AUD). This study aims to investigate the frequency and triggers of cravings in the daily lives of people with alcohol-related issues. Large amounts of data are analyzed with Artificial Intelligence (AI) methods to identify possible groupings and patterns.

METHODS

For the analysis, posts from the online forum "stopdrinking" on the Reddit platform were used as the dataset from April 2017 to April 2022. The posts were filtered for craving content and processed using the word2vec method to map them into a multi-dimensional vector space. Statistical analyses were conducted to calculate the nature and frequency of craving contexts and triggers (location, time, social environment, and emotions) using word similarity scores. Additionally, the themes of the craving-related posts were semantically grouped using a Latent Dirichlet Allocation (LDA) topic model. The accuracy of the results was evaluated using two manually created test datasets.

RESULTS

Approximately 16% of the forum posts discuss cravings. The number of craving-related posts decreases exponentially with the number of days since the author's last alcoholic drink. The topic model confirms that the majority of posts involve individual factors and triggers of cravings. The context analysis aligns with previous craving trigger findings related to the social environment, locations and emotions. Strong semantic craving similarities were found for the emotions boredom, stress and the location airport. The results for each method were successfully validated on test datasets.

CONCLUSIONS

This exploratory approach is the first to analyze alcohol cravings in the daily lives of over 24,000 individuals, providing a foundation for further AI-based craving analyses. The analysis confirms commonly known craving triggers and even discovers new important craving contexts.

Peer-elicited alcohol craving in adolescents and emerging adults: Bridging the laboratory and natural environment

BACKGROUND

Although peers figure prominently in developmental models of alcohol use, our understanding of the influence of peer social context in cue reactivity paradigms with adolescents and emerging adults in the human laboratory and the natural environment is limited. This study tested associations between alcohol craving among youth in the human laboratory using alcohol-related images, with and without peers, and in the natural environment using ecological momentary assessment (EMA).

METHODS

Data for this preregistered secondary analysis were collected prior to randomization in two medication trials (N = 115). Participants completed an image cue exposure paradigm at the baseline laboratory session followed by approximately 7 days of EMA.

RESULTS

In the laboratory, model-based mean comparisons from multilevel models (MLMs) showed that all drinking images elicited greater craving than neutral images. No differences were observed across the three image categories containing alcohol. Image category by age interactions demonstrated that, compared to older youth, younger youth displayed lower craving in response to neutral versus social drinking context with peers images and older, compared to younger, youth displayed higher craving in response to nonsocial drinking images versus social drinking contexts with peers images. In the natural environment, craving was greatest when youth were in the presence of alcohol-using peers and alcohol-related cues, regardless of age. Laboratory craving to alcohol images was positively associated with craving in the natural environment.

CONCLUSIONS

For youth, peers are a salient social context associated with increased craving, particularly in the natural environment. Laboratory cue reactivity to alcohol images predicted real-world craving, further supporting the ecological validity of this paradigm in youth.

Türk İçecek Resim Setinin Geçerliği ve Standardizasyonu: Bilişsel Yanlılık Ölçümü ve Modifikasyon Paradigmaları İçin Kontrollü Resim Seti

Amaç: Bu çalışmada alkol içerikli uyaranlara ilişkin bilişsel yanlılık ölçüm ve modifikasyonu araştırmalarında kullanılabilecek, Türk örneklemi üzerinde geçerliliği ve standardizasyonu yapılmış içecek resim seti oluşturulması amaçlanmıştır. Gereç ve Yöntem: Alkollü ve alkolsüz içecek resimleri 3 pasif bağlamda (dolu bir şişede içecek, boş bir bardakla dolu bir şişe ve dolu bir bardakla dolu bir şişe içecek) ve 3 aktif bağlamda (içecek servis edilirken, açılırken ve tüketilirken) fotoğraflanmıştır. Sonrasında 120 üniversite öğrencisine Alkol Kullanım Bozukluğu Tarama Testi, içecek resimlerini tanıma ve derecelendirme deneyleri uygulanmıştır. Bulgular: Türk İçecek Resim Seti kolaylıkla tanınabilen, popülasyon tarafından sıklıkla tüketilen içecek resimlerinden oluşmaktadır. Alkollü içecek resimleri ağır içici grupta daha fazla içme isteği uyandırabilmiştir. Pasif bağlamda sunulan içecekler aktif resimlere göre daha hızlı tanınmıştır. Sonuç: Türk İçecek Resim Seti, alkol bağımlılığında örtük bilişsel süreçleri araştırmak için çeşitli deneysel paradigmalarda kullanılabilecektir.

Using computer-based habit versus chess-based cognitive remediation training as add-on therapy to modify the imbalance between habitual behavior and cognitive control in tobacco use disorder: protocol of a randomized controlled, fMRI study

BACKGROUND

Although the vast majority of smokers are aware of the enormous preventable health hazards caused by smoking, only a small percentage of smokers manage to remain abstinent in the long term. One possible explanation for this discrepancy lies in the inflexibility of addictive behavior and associated disadvantageous decision-making. According to a dual-process theory of decision-making, two distinct decision systems can be identified. One slow deliberate system based on desirable expectations of outcome value described as goal-directed behavior and a fast reflexive system based on habitual instrumental behavior and driven by reinforcement experienced in the past. In the course of addiction development, an imbalance occurs between habitual behavior and goal-directed. The present study aims to investigate the modifiability of the balance between habitual and goal-directed behavior at the neurobiological and behavioral level in smokers using two different novel add-on therapies. We hypothesize that both interventions change the balance between goal-directed and habitual behavior, but by different mechanisms. Whereas a cognitive remediation treatment should directly improve cognitive control, in contrast an implicit priming task should affect the early processing and the emotional valence of smoking and smoking cues.

METHODS

We will conduct a randomized controlled study in treatment-seeking individuals with tobacco use disorder applying either chess-based cognitive remediation training (N = 30) or implicit computer-based habit-modifying training (N = 30) as add on therapy compared to the standard smoking cessation group therapy (N = 30) only. We will address neurobiological and neuropsychological correlates associated with craving, reward devaluation, cue reactivity and attentional bias. In addition, various effects of treatment and prediction of treatment outcome will be examined using behavioral and neural measures.

DISCUSSION

The present study will apply different examination methods such as functional magnetic resonance imaging, neuropsychological tests, and self-report before and after the interventions. This allows the identification of intervention-specific mechanisms and therefore potential neurobiology-based specific treatment targets for individuals with Tobacco Use Disorder.

TRIAL REGISTRATION

Registered at clinicaltrials.gov/ct2/show/NCT03764969 (05 December 2018).

VR for Studying the Neuroscience of Emotional Responses

Emotions are frequently considered as the driving force of behavior, and psychopathology is often characterized by aberrant emotional responding. Emotional states are reflected on a cognitive-verbal, physiological-humoral, and motor-behavioral level but to date, human research lacks an experimental protocol for a comprehensive and ecologically valid characterization of such emotional states. Virtual reality (VR) might help to overcome this situation by allowing researchers to study mental processes and behavior in highly controlled but reality-like laboratory settings. In this chapter, we first elucidate the role of presence and immersion as requirements for eliciting emotional states in a virtual environment and discuss different VR methods for emotion induction. We then consider the organization of emotional states on a valence continuum (i.e., from negative to positive) and on this basis discuss the use of VR to study threat processing and avoidance as well as reward processing and approach behavior. Although the potential of VR has not been fully realized in laboratory and clinical settings yet, this technological tool can open up new avenues to better understand the neurobiological mechanisms of emotional responding in healthy and pathological conditions.

Using Imagination to Integrate Contextual Effects in a Cue-Reactivity Paradigm in Patients with Alcohol Use Disorder: A Functional Magnetic Resonance Imaging Pilot Study

INTRODUCTION

In individuals with alcohol use disorder (AUD), the brain areas underlying cue-induced reactions (e.g., cingulum, striatum, thalamus) and altered activation of these regions have been identified by functional neuroimaging. Neuronal responses to a complex alcohol-related context are yet to investigate. To better understand contextual effects as well as the interplay of cue-induced neural reactions and context exposure, the present study implemented an imagination procedure during functional magnetic resonance imaging (fMRI).

METHODS

Thirteen patients with AUD and 13 healthy controls completed two rounds of a cue-reactivity paradigm inside an MRI scanner. Two individualized imagination tasks were conducted before each of the two cue reactivity tasks. A 2 (group) × 2 (imagination) × 2 (picture-type) analysis of variance (ANOVA) was performed.

RESULTS

The ANOVA revealed a main effect for imagination with higher activation in bilateral thalamus and right caudate nucleus and an interaction effect between imagination and group in right thalamus and left caudate nucleus, due to the patient group reacting stronger during alcohol-related imagination. These structures are involved in relaying sensory information and habit learning. No main or interaction effects of picture type were observed.

CONCLUSIONS

These results support the view that context effects alter the neural responses in thalamus and nucleus caudatus in patients with AUD, and that imagination tasks are suited to incorporate contextual influences in neurophysiological research designs. Future research needs to investigate whether the failure to observe a picture-type effect was due to limited statistical power and omission to individualize picture set, or whether an imagination procedure interferes with the evocation of picture-type effects.

Clinical Outcomes of Severe Forms of Early Social Stress

Early social stress, particularly severe but nevertheless frequent forms such as abuse and neglect, are among the major risk factors for the development of mental disorders. However, we only have very limited knowledge of the psychobiological disease mechanisms underlying the influence of early life stress and stress-related disorders during this vulnerable phase of life. Early stress can have long-lasting adverse effects on the brain and other somatic systems, e.g. through influences on brain development. In adulthood, the prior experience of abuse or neglect can result in complex clinical profiles. Besides conditions such as mood and anxiety disorders as well as posttraumatic stress disorder, substance use disorders (SUD) are among the most prevalent sequelae of early social stress. Current social stress further influences the development and maintenance of these disorders, e.g., by increasing the risk of relapses. In this chapter, we will first give an overview of currently used methods to assess the phenomenology and pathophysiology of stress-related disorders and then focus on the phenomenological and neurobiological background of the interaction between early social stress and SUD. We will give an overview of important insights from neuroimaging studies and will also highlight recent findings from studies using digital tools such as ecological momentary assessment or virtual reality to capture the influence of early social stress as well as current social stress in everyday life of persons with SUD.

Reward Processing and Circuit Dysregulation in Posttraumatic Stress Disorder

Past decades have witnessed substantial progress in understanding of neurobiological mechanisms that contribute to generation of various PTSD symptoms, including intrusive memories, physiological arousal and avoidance of trauma reminders. However, the neurobiology of anhedonia and emotional numbing in PTSD, that have been conceptualized as reward processing deficits - reward wanting (anticipation of reward) and reward liking (satisfaction with reward outcome), respectively, remains largely unexplored. Empirical evidence on reward processing in PTSD is rather limited, and no studies have examined association of reward processing abnormalities and neurocircuitry-based models of PTSD pathophysiology. The manuscript briefly summarizes "state of the science" of both human reward processing, and of PTSD implicated neurocircuitry, as well as empirical evidence of reward processing deficits in PTSD. We then summarize current gaps in the literature and outline key future directions, further illustrating it by the example of two alternative explanations of PTSD pathophysiology potentially affecting reward processing via different neurobiological pathways. Studying reward processing in PTSD will not only advance the understanding of their link, but also could enhance current treatment approaches by specifically targeting anhedonia and emotional symptoms in PTSD patients.

SmoCuDa: A Validated Smoking Cue Database to Reliably Induce Craving in Tobacco Use Disorder

BACKGROUND

Cue-reactivity paradigms provide valuable insights into the underlying mechanisms of nicotine craving in nicotine-dependent subjects. In order to study cue-driven nicotine craving, robust and validated stimulus datasets are essential.

OBJECTIVES

The aim of this study was to generate and validate a large set of individually rated smoking-related cues that allow for assessment of different stimulus intensities along the dimensions craving, valence, and arousal.

METHODS

The image database consisted of 330 visual cues. Two hundred fifty smoking-associated pictures (Creative Commons license) were chosen from online databases and showed a widespread variety of smoking-associated content. Eighty pictures from previously published databases were included for cross-validation. Forty volunteers with tobacco use disorder rated "urge-to-smoke," "valence," and "arousal" for all images on a 100-point visual analogue scale. Pictures were also labelled according to 18 categories such as lit/unlit cigarettes in mouth, cigarette end, and cigarette in ashtray.

RESULTS

Ratings (mean ± SD) were as follows: urge to smoke, 44.9 ± 13.2; valence, 51.2 ± 7.6; and arousal, 54.6 ± 7.1. All ratings, particularly "urge to smoke," were widely distributed along the whole scale spectrum.

CONCLUSIONS

We present a novel image library of well-described smoking-related cues, which were rated on a continuous scale along the dimensions craving, valence, and arousal that accounts for inter-individual differences. The rating software, image database, and their ratings are publicly available at https://smocuda.github.io.

Network failures: When incentives trigger impulsive responses

Adequate control of impulsive urges to act is demanded in everyday life but is impaired in neuropsychiatric conditions such as stimulant use disorder. Despite intensive research it remains unclear whether failures in impulse control are caused by impaired suppression of behavior or by the over invigoration of behavior by stimuli associated with salient incentives such as drugs, food, and money. We investigated failures in impulse control using functional magnetic resonance imaging (fMRI) to map the neural correlates of premature (impulsive) responses during the anticipation phase of the Monetary Incentive Delay (MID) task in healthy controls (HC), stimulant-dependent individuals (SDIs), and their unaffected first-degree siblings (SIB). We combined task-based fMRI analyses with dynamic causal modeling to show that failures of impulse control were associated with interactions between cingulo-opercular and dorsal striatal networks regardless of group status and incentive type. We further report that group-specific incentive salience plays a critical role in modulating impulsivity in SDIs since drug-related incentives specifically increased premature responding and shifted task modulation away from the dorsal striatal network to the cingulo-opercular network. Our findings thus indicate that impulsive actions are elicited by salient personally-relevant incentive stimuli and those such slips of action recruit a distinct fronto-striatal network.

Individual variation in the attribution of incentive salience to social cues

Research on the attribution of incentive salience to drug cues has furthered our understanding of drug self-administration in animals and addiction in humans. The influence of social cues on drug-seeking behavior has garnered attention recently, but few studies have investigated how social cues gain incentive-motivational value. In the present study, a Pavlovian conditioned approach (PCA) procedure was used to identify rats that are more (sign-trackers; STs) or less (goal-trackers; GTs) prone to attribute incentive salience to food reward cues. In Experiment 1, a novel procedure employed social ‘peers’ to compare the tendency of STs and GTs to attribute incentive salience to social reward cues as well as form a social-conditioned place preference. In Experiment 2, social behavior of STs and GTs was compared using social interaction and choice tests. Finally, in Experiment 3, levels of plasma oxytocin were measured in STs and GTs seven days after the last PCA training session, because oxytocin is known to modulate the mesolimbic reward system and social behavior. Compared to GTs, STs attributed more incentive salience to social-related cues and exhibited prosocial behaviors (e.g., social-conditioned place preference, increased social interaction, and social novelty-seeking). No group differences were observed in plasma oxytocin levels. Taken together, these experiments demonstrate individual variation in the attribution of incentive salience to both food- and social-related cues, which has important implications for the pathophysiology of addiction.

Wake Forest Alcohol Imagery Set: Development and Validation of a Large Standardized Alcohol Imagery Dataset

BACKGROUND

The study of alcohol use frequency utilizes alcohol-related cue imagery. Although a number of alcohol-image databases currently exist, they have several limitations: Many are not publicly available, some use stock images or clip art rather than real photographs, several eliminate any photographs displaying brand information, and predominantly they contain relatively few images. The aim of this project was to develop a large, open-access database of alcohol-related cue images, containing photographs with and without brand information, taken in real-world environments, with images in a variety of orientations and dimensions.

METHODS

The study collected 1,650 images voluntarily from the larger community, to capture photographs with a wide range of content, environments, and relation to alcohol. All images were then rated on scales of valence, arousal, and relation to alcohol by 1,008 Amazon Mechanical Turk workers, using classical emotion validation methods based on the International Affective Picture System (IAPS). Survey respondents were screened with the Alcohol Use Disorders Identification Test (AUDIT), and Cronbach's alpha scores were calculated to determine the interrater reliability of scores across the whole sample, and within low-risk, moderate-risk, and high-risk drinkers for each rating domain. Univariate ANOVAs were run to determine differences in ratings across drinking groups.

RESULTS

All Cronbach's alpha scores indicated high interrater reliability within the whole sample, and across drinking severity groups. Tukey's HSD post hoc results indicated greater arousal and affect in response to image viewing in moderate- and high-risk drinkers, and higher relation-to-alcohol ratings in low-risk drinkers. All images had categorization tags assigned by members of the study team.

CONCLUSIONS

The established imagery set includes 1,650 alcohol-related images, rated on scales of valence, arousal, and relation to alcohol, and categorized by type of alcohol depicted. The imagery database will be available for open-access download and use through Google Photos.

Reward sensitivity and electrodermal responses to actions and outcomes in a go/no-go task

Skin conductance response (SCR) is used in psychophysiological research to measure the reactions of the autonomic nervous system to reward and punishment. While there is consistent evidence that SCR increases to both aversive and appetitive stimuli, it remains unclear whether SCR simply represents a general index of arousal to motivationally significant outcomes or may also differentiate action or inhibition of action that lead to such outcomes. Furthermore, individual differences in trait sensitivity to reward and punishment can influence physiological arousal during approach and avoidance behaviors. Yet, their inter-relationships have not been examined. To address these gaps, we employed a reward go/no-go task with ⅔ go and ⅓ no-go trials and an individually titrated go response window. Correct go and no-go responses were rewarded while incorrect responses were penalized. We examined whether SCR varied with outcome (win vs. loss), action (go vs. no-go), and individual differences in reward sensitivity (SR) and sex. The results showed greater SCRs to loss vs. win, to go vs. no-go success, and to go success in positive correlation with SR. Further, SCR mediated the relationship between SR and go success rate. In sex differences, men exhibited greater SCR which was more predictive of go success rate relative to women. In contrast, SCR was more predictive of no-go success rate in women. Thus, SCR varies according to behavioral contingency, outcome, sex, and reward sensitivity. These findings add to the literature by characterizing the individual and behavioral factors that may influence physiological arousal in response to salient events.

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.

Identifying Triggers of Alcohol Craving to Develop Effective Virtual Environments for Cue Exposure Therapy

Background: Many studies have indicated that alcohol craving is a core mechanism in the acquisition, maintenance, and precipitation of relapse in alcohol use disorder (AUD). A common treatment approach in AUD is cue exposure therapy (CET). New technologies like virtual reality (VR) have the potential to enhance the effectiveness of CET by creating realistic scenarios in naturalistic environments. In this study, we aimed to determine relevant triggers of alcohol craving in patients with AUD.

Methods: We enrolled 75 outpatients diagnosed with AUD according to the DSM-5 criteria Participants completed the Alcohol Use Disorder Identification Test and a self-administered questionnaire to assess alcohol craving. The variables included in the craving questionnaire were as follows: presence of others, situations, time of the day, day of the week, mood, and type of alcoholic beverage.

Results: Greater levels of alcohol craving were seen in many situations, including being at a party, in a restaurant, in a bar or pub, and at home. Drinking alone and drinking with two or more friends were equally associated with higher levels of craving. Drinking at night and drinking at weekends also emerged as triggers for alcohol craving. Emotional states like anxiety or tension, sadness, stress, frustration, or irritability were highly associated with urges to drink alcohol. The alcoholic drinks most highly associated with increased levels of craving were beer, wine, and whisky. Gender and age implications were discussed.

Conclusion: This study is part of a larger project aiming to develop and validate CET based on VR technology for patients with AUD who are resistant to classical treatment. The identified triggers have been used to develop relevant VR environments for CET, and further research is ongoing to implement our findings.

Modeling Relapse to Pavlovian Alcohol-Seeking in Rats Using Reinstatement and Spontaneous Recovery Paradigms

BACKGROUND

Animal models are critical for studying causal explanations of relapse. Using a Pavlovian conditioning procedure with alcohol, we examined relapse after extinction triggered by either re-exposure to alcohol (reinstatement) or a delay between extinction and test (spontaneous recovery).

METHODS

Male, Long-Evans rats were acclimated to 15% alcohol in the home-cage using an intermittent-access 2-bottle choice procedure. Next, they received Pavlovian conditioning sessions in which an auditory-conditioned stimulus (CS; 20 second white noise; 8 trials/session; variable time 240 seconds) was paired with 15% alcohol (0.3 ml/CS; 2.4 ml/session) that was delivered into a fluid port for oral ingestion. In subsequent extinction and test sessions, CS presentations occurred as before, but without alcohol.

RESULTS

In experiment 1, exposure to either alcohol or water in the fluid port following extinction reinstated CS-elicited port entries at test 24 hours later. In a follow-up study using the same procedure (experiment 2), reinstatement was more robustly stimulated by alcohol, compared to a familiar lemon-flavored liquid. In experiment 3, systemic alcohol injections (0, 0.5, or 1.0 g/kg, intraperitoneal) administered either 24 hours or 15 minutes before test did not reinstate CS-elicited alcohol-seeking. Importantly, enzymatic assays in experiment 4 revealed detectable levels of alcohol in the blood following oral alcohol intake or intraperitoneal injection, suggesting that a pharmacological effect was likely with either route of administration. Last, in experiment 5, a 23-day delay between extinction and test resulted in a robust spontaneous recovery of CS-elicited alcohol-seeking.

CONCLUSIONS

The reinstatement and spontaneous recovery effects revealed herein provide evidence of viable new behavioral paradigms for testing interventions against relapse.

The Galician Beverage Picture Set (GBPS): A standardized database of alcohol and non-alcohol images

BACKGROUND

The available picture sets in alcohol research are scarce and display a number of limitations, including poor picture quality, limited number of stimuli and absence of non-alcohol and/or real-life images. In the present study, we developed the Galician Beverage Picture Set (GBPS), a database of high-quality alcohol and non-alcohol pictures embedded in real-life scenarios.

METHODS

A total of 201 college students (∼59% females) were assessed by the Alcohol Use Disorders Identification Test, ∼54% being characterized as no/low drinkers (N/LDs) and ∼46% as risky drinkers (RDs). The GBPS included six types of beverages: beer, wine, liquor (alcoholic drinks); water, juice, milk (non-alcoholic drinks). Additionally, two subcategories were considered: orientation (landscape, portrait) and number of people (0, 1, ≥2 people). Participants rated the images for valence, arousal and visual complexity. Objective measures of brightness and color and recognition rates were also assessed. Internal consistency was estimated using Cronbach's alpha coefficient.

RESULTS

There was a high degree of internal consistency within each category (alcoholic and non-alcoholic drinks) for valence, arousal and visual complexity scores. A mixed-model ANOVA revealed that RDs rated alcohol pictures as more pleasant and arousing than N/LDs. Conversely, N/LDs displayed greater valence and arousal ratings than RDs for non-alcohol pictures.

CONCLUSIONS

The GBPS provides normative data on affective (valence/arousal), perceptual (visual complexity) and physical (brightness/color) values for a large number of images that may be useful for alcohol-related research. Differences in subjective assessments between N/LDs and RDs support the picture set's suitability for studies in young drinkers.

Mobile Health Technology Using a Wearable Sensorband for Female College Students With Problem Drinking: An Acceptability and Feasibility Study

BACKGROUND

An increasing number of mobile app interventions have been developed for problem drinking among college students; however, few studies have examined the integration of a mobile app with continuous physiological monitoring and alerting of affective states related to drinking behaviors.

OBJECTIVE

The aim of this paper was to evaluate the acceptability and feasibility of Mind the Moment (MtM), a theoretically based intervention for female college students with problem drinking that combines brief, in-person counseling with ecological momentary intervention (EMI) on a mobile app integrated with a wearable sensorband.

METHODS

We recruited 10 non-treatment seeking, female undergraduates from a university health clinic who scored a 3 or higher on the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) to participate in this pilot study. Study activities involved an in-person baseline intake and 1 follow-up assessment, 2 in-person alcohol brief intervention counseling sessions, and use of MtM technology components (sensorband and EMI on a mobile app) for approximately 3-4 weeks. The intervention used motivational interviewing (MI) and cognitive behavioral therapy (CBT) strategies for reducing risks associated with drinking. We used both qualitative and quantitative assessments to measure acceptability of the intervention and feasibility of delivery. Use patterns of the sensorband and mobile app were also collected.

RESULTS

Quantitative and qualitative data indicated high levels of acceptability for the MtM intervention. Altogether, participants made reports on the app on 26.7% (78/292) the days the technology was available to them and completed a total of 325 reports with wide variation between participants. Qualitative findings indicated that sensorband-elicited alerts promoted an increase in awareness of thoughts, feelings, and behaviors related to current environmental stressors and drinking behaviors in theoretically meaningful ways. Specific challenges related to functionality and form of the sensorband were identified.

CONCLUSIONS

Delivering intervention material "just-in-time," at the moment participants need to use behavioral strategies has great potential to individualize behavioral interventions for reducing problem drinking and other health behaviors. These findings provide initial evidence for the promise of wearable sensors for increasing potency of theoretically grounded mobile health interventions and point to directions for future research and uptake of these technologies.

Implicit Learning in Transient Global Amnesia and the Role of Stress

Transient global amnesia (TGA) is a disorder with reversible anterograde disturbance of explicit memory, frequently preceded by an emotionally or physically stressful event. By using magnetic resonance imaging (MRI) following an episode of TGA, small hippocampal lesions have been observed. Hence it has been postulated that the disorder is caused by the stress-related transient inhibition of memory formation in the hippocampus. In experimental studies, stress has been shown to affect both explicit and implicit learning—the latter defined as learning and memory processes that lack conscious awareness of the information acquired. To test the hypothesis that impairment of implicit learning in TGA is present and related to stress, we determined the effect of experimental exposure to stress on hippocampal activation patterns during an implicit learning paradigm in patients who suffered a recent TGA and healthy matched control subjects. We used a hippocampus-dependent aversive learning procedure (context conditioning with the phases habituation, acquisition, and extinction) during functional MRI following experimental stress exposure (socially evaluated cold pressor test). After a control procedure, controls showed successful learning during the acquisition phase, indicated by increased valence, arousal and contingency ratings to the paired (CON+) vs. the non-paired (CON−) conditioned stimulus, and successful extinction of the conditioned responses. Following stress, acquisition was still successful, however extinction was impaired with persistently increased contingency ratings. In contrast, TGA patients showed impairment of conditioned responses and insufficient extinction after the control procedure, indicated by a lack of significant differences between CON+ and CON− for valence and arousal ratings after the acquisition phase and by significantly increased contingency ratings after the extinction. After stress, aversive learning was not successful with non-significant ratings of all parameters. Concerning brain activation patterns after the control procedure, controls showed increased hippocampal response during acquisition after the control procedure. This was not seen after stress exposure. In TGA patients, we observed an increased response in the right ventral striatum in the acquisition phase following stress. These findings suggest that alterations in implicit learning processes, including impaired hippocampal and increased striatal responses, might play a role in TGA pathophysiology, partly related to acute stress.

American Alcohol Photo Stimuli (AAPS): A standardized set of alcohol and matched non-alcohol images

BACKGROUND

Photographic stimuli are commonly used to assess cue reactivity in the research and treatment of alcohol use disorder. The stimuli used are often non-standardized, not properly validated, and poorly controlled. There are no previously published, validated, American-relevant sets of alcohol images created in a standardized fashion.

OBJECTIVES

We aimed to: 1) make available a standardized, matched set of photographic alcohol and non-alcohol beverage stimuli, 2) establish face validity, the extent to which the stimuli are subjectively viewed as what they are purported to be, and 3) establish construct validity, the degree to which a test measures what it claims to be measuring.

METHODS

We produced a standardized set of 36 images consisting of American alcohol and non-alcohol beverages matched for basic color, form, and complexity. A total of 178 participants (95 male, 82 female, 1 genderqueer) rated each image for appetitiveness. An arrow-probe task, in which matched pairs were categorized after being presented for 200 ms, assessed face validity. Criteria for construct validity were met if variation in AUDIT scores were associated with variation in performance on tasks during alcohol image presentation.

RESULTS

Overall, images were categorized with >90% accuracy. Participants' AUDIT scores correlated significantly with alcohol "want" and "like" ratings [r(176) = 0.27, p = <0.001; r(176) = 0.36, p = <0.001] and arrow-probe latency [r(176) = -0.22, p = 0.004], but not with non-alcohol outcomes. Furthermore, appetitive ratings and arrow-probe latency for alcohol, but not non-alcohol, differed significantly for heavy versus light drinkers.

CONCLUSION

Our image set provides valid and reliable alcohol stimuli for both explicit and implicit tests of cue reactivity. The use of standardized, validated, reliable image sets may improve consistency across research and treatment paradigms.

Conditioned object preference: an alternative approach to measuring reward learning in rats

Pavlovian conditioned approach behavior can be directed as much toward discrete cues as it is toward the environmental contexts in which those cues are encountered. The current experiments characterized a tendency of rats to approach object cues whose prior exposure had been paired with reward (conditioned object preference, COP). To demonstrate the phenomenon, rats were conditioned to associate cocaine or saline with two different objects. Rats acquired a preference, assessed using investigation times directed toward each object, for the cocaine-paired object following conditioning. Furthermore, high levels of object investigation during cocaine conditioning predicted stronger preferences for the cocaine-paired object in the test phase. Conditioned approach diminished across extinction but was reinstated through a priming injection of cocaine. To determine whether preferences are affected by reward value, rats were conditioned using three objects paired with 0, 5, or 20 mg/kg of cocaine. This produced object preferences in the post-test that scaled with cocaine dose used for conditioning. Finally, we explored whether contextual cues modulate expression of COP by testing rats for renewal of cocaine seeking. When conditioning was conducted in one context and extinction training in a second context, COP was renewed when the rats were retested in the original context. Thus, conditioned object preferences are readily acquired, easily measured, and amenable to a number of standard Pavlovian conditioning manipulations. This task promises to become a valuable addition to the panoply of behavioral tools available to test mechanisms underlying adaptive and maladaptive reward processing.

Validation of the Amsterdam Beverage Picture Set: A Controlled Picture Set for Cognitive Bias Measurement and Modification Paradigms

Background

Alcohol research may benefit from controlled and validated picture sets. We have constructed the Amsterdam Beverage Picture Set (ABPS), which was designed for alcohol research in general and cognitive bias measurement and modification in particular. Here, we first formulate a position on alcohol stimulus validity that prescribes that alcohol‐containing pictures, compared to nonalcohol‐containing pictures, should induce a stronger urge to drink in heavy drinkers than in light drinkers. Because a perceptually simple picture might induce stronger cognitive biases but the presence of a drinking context might induce a stronger urge to drink, the ABPS contains pictures with and without drinking context. By limiting drinking contexts to simple consumption scenes instead of real‐life scenes, complexity was minimized. A validation study was conducted to establish validity, to examine ABPS drinking contexts, and to explore the role of familiarity, valence, arousal, and control.

Methods

Two hundred ninety‐one psychology students completed the Alcohol Use Disorders Identification Test, as well as rating and recognition tasks for a subset of the ABPS pictures.

Results

The ABPS was well‐recognized, familiar, and heavy drinkers reported a greater urge to drink in response to the alcohol‐containing pictures only. Alcohol presented in drinking context did not elicit a stronger urge to drink but was recognized more slowly than alcohol presented without context.

Conclusions

The ABPS was found to be valid, although pictures without context might be preferable for measuring cognitive biases than pictures with context. We discuss how an explicit approach to picture construction may aid in creating variations of the ABPS. Finally, we describe how ABPS adoption across studies may allow more reproducible and comparable results across paradigms, while allowing researchers to apply picture selection criteria that correspond to a wide range of theoretical positions. The latter is exemplified by ABPS derivatives and adoptions that are currently under way.

The role of social stimuli content in neuroimaging studies investigating alcohol cue-reactivity

INTRODUCTION

Cue-reactivity is thought to play a fundamental role in the maintenance of addiction. The incentive sensitization theory proposes that conditioned responses are related to increased sensitivity of the reward-related dopaminergic pathways in the brain. However, neuroimaging studies on alcohol cue-reactivity show inconsistent results.

METHODS

Stimuli content of 26 alcohol cue-reactivity studies was systematically reviewed.

RESULTS

No differences were found between alcoholic beverage stimuli and non-alcoholic beverage stimuli in human display and brand factors; however, alcoholic beverage stimuli were more likely to display social interaction compared to non-alcoholic beverage stimuli.

CONCLUSIONS

Given that processing of social information activates brain areas that partly overlap with reward-related brain areas associated with cue-reactivity, such differences between conditions can introduce noise in the findings. We therefore suggest matching stimuli sets on the reviewed factors carefully to improve reliability of neuroimaging studies investigating alcohol-related cue-reactivity.

Social network moderators of naltrexone and behavioral treatment effects on heavy drinking in the COMBINE study

BACKGROUND

Oral naltrexone is an efficacious medication for treatment of alcohol dependence, but small effect sizes and variability in outcomes suggest the presence of person-level moderators of naltrexone response. Identification of contextual or psychosocial moderators may assist in guiding clinical recommendations. Given the established importance of social networks in drinking outcomes, as well as the potential effects of naltrexone in reducing cue reactivity which may be especially important among those with more heavy drinkers and more alcohol cues in their networks, we examined pretreatment social network variables as potential moderators of naltrexone treatment effects in the COMBINE study.

METHODS

The sample included all COMBINE study participants in medication conditions with full data on the Important People Inventory (IPI) and covariates at intake (N = 1,197). The intake IPI assessed whether participants had any frequent drinkers in their network and the average frequency of contact with these drinkers. The effects of treatment condition, pretreatment network variables, and their interactions on percent heavy drinking days were tested in hierarchical linear models, controlling for demographics and baseline clinical covariates.

RESULTS

In treatment conditions involving medical management and combined behavioral intervention (CBI), the effects of active naltrexone on heavy drinking were significantly greater for individuals with frequent drinkers in their network (z = -2.66, p < 0.01) and greater frequency of contact with those drinkers (z = -3.19, p < 0.01). These network variables did not moderate the effects of active naltrexone without CBI.

CONCLUSIONS

When delivered in conjunction with behavioral interventions, naltrexone can be more potent for alcohol-dependent adults who have greater contact with frequent drinkers prior to treatment, which may indicate patterns of environmental exposure to alcohol. Contextual, social risk factors are a potential avenue to guide personalized treatment of alcohol dependence.

Cue-induced craving to paraphernalia and drug images in opioid dependence

BACKGROUND AND OBJECTIVES

Stimuli that are repeatedly paired with substance use, such as drug paraphernalia, can themselves elicit drug craving. The aim of this study was to examine whether particular cue types elicit greater craving responses than others among individuals with opioid dependence.

METHODS

Participants seeking inpatient treatment for opioid dependence were recruited for a study of cue-induced craving. This sample (N = 50), included 25 primary heroin users, 20 primary prescription opioid users, and 5 users of heroin and prescription opioids equally. Participants completed a cue reactivity task, in which images of drug-related stimuli were presented on a computer screen, each followed by a question assessing state drug craving.

RESULTS

Overall, participants reported higher craving following paraphernalia stimuli relative to drug stimuli. However, this was moderated by opioid type; there was significantly higher craving in response to images of paraphernalia cues in the heroin group, and higher craving in response to drug cues in the prescription opioid group.

DISCUSSION AND CONCLUSIONS

These findings highlight potential differences in cue reactivity to opioid paraphernalia and drug cues, which appears to be moderated by drug type.

SCIENTIFIC SIGNIFICANCE

Cue-induced craving is an important factor in relapse. This study adds further to the literature on cue-induced craving in opioid dependence, suggesting that craving may vary based on both cue type and opioid type. Future studies designed to discriminate the impact of substance of abuse, route of administration, and cue type will help to further clarify cue-induced craving in this population.

Smells like inhibition: The effects of olfactory and visual alcohol cues on inhibitory control

RATIONALE

How the smell of alcohol impacts alcohol-related thoughts and behaviours is unclear, though it is well-documented that alcohol-related stimuli and environments may trigger these.

OBJECTIVES

The current study, therefore, aimed to investigate the priming effects of both visual and olfactory alcohol cues on inhibitory control.

METHOD

Forty individuals (M age = 23.65, SD = 6.52) completed a go/no-go association task (GNAT) which measured reaction times, response accuracy and false alarm rates whilst being exposed to alcohol-related (or neutral) olfactory and visual cues.

RESULTS

Alcohol-related visual cues elicited lower false alarm rates, slower reaction times and higher accuracy rates relative to neutral pictorial cues. False alarm rates were significantly higher for those exposed to alcohol as opposed to neutral olfactory cues.

CONCLUSIONS

By highlighting that exposure to alcohol-related olfactory cues may impede response inhibition, the results indicate that exposure to such stimuli may contribute to the activation of cognitive responses which may drive consumption.

Alcohol-Seeking Triggered by Discrete Pavlovian Cues is Invigorated by Alcohol Contexts and Mediated by Glutamate Signaling in the Basolateral Amygdala

The environmental context in which a discrete Pavlovian conditioned stimulus (CS) is experienced can profoundly impact conditioned responding elicited by the CS. We hypothesized that alcohol-seeking behavior elicited by a discrete CS that predicted alcohol would be influenced by context and require glutamate signaling in the basolateral amygdala (BLA). Male, Long-Evans rats were allowed to drink 15% ethanol (v/v) until consumption stabilized. Next, rats received Pavlovian conditioning sessions in which a 10 s CS (15 trials/session) was paired with ethanol (0.2 ml/CS). Entries into a port where ethanol was delivered were measured. Pavlovian conditioning occurred in a specific context (alcohol context) and was alternated with sessions in a different context (non-alcohol context) where neither the CS nor ethanol was presented. At test, the CS was presented without ethanol in the alcohol context or the non-alcohol context, following a bilateral microinfusion (0.3 μl/hemisphere) of saline or the AMPA glutamate receptor antagonist NBQX (2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide disodium salt) in the BLA (0, 0.3, or 1.0 μg/0.3 μl). The effect of NBQX (0, 0.3 μg/0.3 μl) in the caudate putamen (CPu) on CS responding in the non-alcohol context was also tested. The discrete alcohol CS triggered more alcohol-seeking behavior in the alcohol context than the non-alcohol context. NBQX in the BLA reduced CS responding in both contexts but had no effect in the CPu. These data indicate that AMPA glutamate receptors in the BLA are critical for alcohol-seeking elicited by a discrete CS and that behavior triggered by the CS is strongly invigorated by an alcohol context.

Combining cognitive bias modification training with motivational support in alcohol dependent outpatients: study protocol for a randomised controlled trial

BACKGROUND

Addiction research has hypothesised that automatic and reflective cognitive processes play an important role in the onset and maintenance of alcohol (ab)use, wherein automatic reactions to drug-related cues steer the drug user towards consuming before reflective processes can get over and steer towards a different behavioural response. These automatic processes include the tendency to attend and approach alcohol cues. These biases may be trained away from alcohol via computerised cognitive bias modification (CBM). The present protocol describes the design of a double-blind randomised controlled trial (RCT) testing the effectiveness of attentional bias and approach bias re-training with a 2×2 factorial design, alongside a brief motivational support (MS) program.

METHODS/DESIGN

Participants (n = 120) are adult alcohol dependent outpatients, recruited from a public health service for addiction in Italy, who have been abstinent for at least two months, and with a main diagnosis of alcohol dependence disorder. Participants are randomly assigned to one of four experimental conditions and complete 11 sessions of training after a baseline assessment. The MS takes place before each training session. Post-intervention and three-month follow-up assessments examine the change in clinical outcome variables and attentional and approach biases (measured with the Visual Probe Task and the Approach-Avoidance Task, respectively). Alcohol approach-avoidance implicit memory associations (measured with the Brief Implicit Association Test) are also evaluated at pre- and post-intervention to explore generalisation effects. Primary outcome measure is relapse rate at follow-up. Secondary outcome measures include change in cognitive biases, in alcohol-related implicit memory associations, and in the clinical variables assessed. An exploratory analysis is also planned to detect interaction effects between the CBM modules and possible moderators (interference control capacity, gender, age, number of previous detoxifications) and mediators (change in cognitive bias) of the primary outcome measure.

DISCUSSION

This RCT is the first to test the effectiveness of a combined CBM intervention alongside motivational support in alcohol-dependent outpatients. The results of this study can be extremely valuable for future research in the optimisation of CBM treatment for alcohol addiction.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN01005959 (registration date: 24 October 2013).

Relations between trait impulsivity, behavioral impulsivity, physiological arousal, and risky sexual behavior among young men

The current study examined how impulsivity-related traits (negative urgency, sensation seeking, and positive urgency), behavioral measures of risk taking and reward seeking, and physiological reactivity related to three different risky sexual behaviors in sexually active undergraduate men (N = 135). Regression analyses indicated that sensation seeking and behavioral risk-taking predicted unique variance in number of sexual partners. These findings suggest that, for young men, acquisition of new partners is associated with need for excitement and reward and willingness to take risks to meet those needs. Sensation seeking, behavioral risk-taking, and skin conductance reactivity to arousing stimuli was related to ever having engaged in sex with a stranger, indicating that, for men, willingness to have sex with a stranger is related not only to the need for excitement and risk-taking but also with innate responsiveness to arousing environmental triggers. In contrast, regression analyses indicated that young men who were impulsive in the context of negative emotions were less likely to use condoms, suggesting that emotion-based impulsivity may be an important factor in negligent prophylactic use. This study adds to the current understanding of the divergence between the correlates of risky sexual behaviors and may lend utility to the development of individualized HIV prevention programming.

Pavlovian-conditioned alcohol-seeking behavior in rats is invigorated by the interaction between discrete and contextual alcohol cues: implications for relapse

INTRODUCTION

Drug craving can be independently stimulated by cues that are directly associated with drug intake (discrete drug cues), as well as by environmental contexts in which drug use occurs (contextual drug cues). We tested the hypothesis that the context in which a discrete alcohol-predictive cue is experienced can influence how robustly that cue stimulates alcohol-seeking behavior.

METHODS

Male, Long-Evans rats received Pavlovian discrimination training (PDT) sessions in which one conditioned stimulus (CS+; 16 trials/session) was paired with ethanol (0.2 mL/CS+) and a second stimulus (CS-; 16 trials/session) was not. PDT occurred in a specific context, and entries into a fluid port where ethanol was delivered were measured during each CS. Next, rats were acclimated to an alternate (nonalcohol) context where cues and ethanol were withheld. Responses to the nonextinguished CS+ and CS- were then tested without ethanol in the alcohol-associated PDT context, the nonalcohol context or a third, novel context.

RESULTS

Across PDT the CS+ elicited more port entries than the CS-, indicative of Pavlovian discrimination learning. At test, the CS+ elicited more port entries than the CS- in all three contexts: however, alcohol seeking driven by the CS+ was more robust in the alcohol-associated context. In a separate experiment, extinguishing the context-alcohol association did not influence subsequent CS+ responding but reduced alcohol seeking during non-CS+ intervals during a spontaneous recovery test.

CONCLUSION

These results indicate that alcohol-seeking behavior driven by a discrete Pavlovian alcohol cue is strongly invigorated by an alcohol context, and suggest that contexts may function as excitatory Pavlovian conditioned stimuli that directly trigger alcohol-seeking behavior.

Sustained incentive value of heroin-related cues in short- and long-term abstinent heroin users

Models of addiction and addiction memory propose that drug-associated cues elicit incentive effects in drug users, which play an important role in maintenance of drug use and relapse. Incentive effects have been demonstrated for smoking and alcohol-related cues but evidence for heroin-related cues has been inconclusive. Furthermore, it is unknown whether appetitive effects of heroin-related cues persist after prolonged abstinence, although heroin addiction is known to have high relapse rates. Therefore, we investigated implicit and explicit valence of heroin-related cues in dependent users at different stages of abstinence using affective startle modulation. In Study I, 15 current heroin users were measured before and after detoxification. Correspondingly, 15 healthy control participants were tested twice at an interval of 14 days. In Study II, 14 long-term abstinent heroin users were additionally measured in a single session. Implicit processing of drug-related stimuli was assessed using affective startle modulation by pictures of heroin and smoking scenes. Explicit reactions were measured using ratings of valence and craving. In contrast to controls, heroin-dependent participants showed a clear reduction of startle response during heroin-related pictures (p<0.05). Detoxification did not significantly change their startle responses to heroin-cues. No difference between non-detoxified current and long-term abstinent heroin users was found in implicit reactions to heroin-cues, whereas explicit measures differed between both groups (all p<0.05). After detoxification and even after prolonged abstinence, heroin cues still exert implicit appetitive effects in heroin users. This implies that drug-induced adaptations of reward circuits are long-lasting, resulting in a highly stable addiction memory.

A flicker change blindness task employing eye tracking reveals an association with levels of craving not consumption

We investigated attentional biases with a flicker paradigm, examining the proportion of alcohol relative to neutral changes detected. Furthermore, we examined how measures of the participants initial orienting of attention and of their maintained attention relate to levels of alcohol consumption and subjective craving in social drinkers. The eye movements of 58 participants (24 male) were monitored whilst they completed a flicker-induced change blindness task using both simple stimuli and real world scenes, with both an alcohol and neutral change competing for detection. When examined in terms of consumption levels, we observed that heavier social drinkers detected a higher proportion of alcohol related changes in real world scenes only. However, we also observed that levels of craving were not indicative of levels of consumption in social drinkers. Furthermore, also in real world scenes only, higher cravers detected a greater proportion of alcohol related changes compared to lower cravers, and were also quicker to initially fixate on alcohol related stimuli. Thus we conclude that processing biases in the orienting of attention to alcohol related stimuli were demonstrated in higher craving compared to lower craving social users in real world scenes. However, this was not related to the level of consumption as would be expected. These results highlight various methodological and conceptual issues to be considered in future research.

Neural responses to smoking stimuli are influenced by smokers' attitudes towards their own smoking behaviour

An important feature of addiction is the high drug craving that may promote the continuation of consumption. Environmental stimuli classically conditioned to drug-intake have a strong motivational power for addicts and can elicit craving. However, addicts differ in the attitudes towards their own consumption behavior: some are content with drug taking (consonant users) whereas others are discontent (dissonant users). Such differences may be important for clinical practice because the experience of dissonance might enhance the likelihood to consider treatment. This fMRI study investigated in smokers whether these different attitudes influence subjective and neural responses to smoking stimuli. Based on self-characterization, smokers were divided into consonant and dissonant smokers. These two groups were presented smoking stimuli and neutral stimuli. Former studies have suggested differences in the impact of smoking stimuli depending on the temporal stage of the smoking ritual they are associated with. Therefore, we used stimuli associated with the beginning (BEGIN-smoking-stimuli) and stimuli associated with the terminal stage (END-smoking-stimuli) of the smoking ritual as distinct stimulus categories. Stimulus ratings did not differ between both groups. Brain data showed that BEGIN-smoking-stimuli led to enhanced mesolimbic responses (amygdala, hippocampus, insula) in dissonant compared to consonant smokers. In response to END-smoking-stimuli, dissonant smokers showed reduced mesocortical responses (orbitofrontal cortex, subcallosal cortex) compared to consonant smokers. These results suggest that smoking stimuli with a high incentive value (BEGIN-smoking-stimuli) are more appetitive for dissonant than consonant smokers at least on the neural level. To the contrary, smoking stimuli with low incentive value (END-smoking-stimuli) seem to be less appetitive for dissonant smokers than consonant smokers. These differences might be one reason why dissonant smokers experience difficulties in translating their attitudes into an actual behavior change.

Current perspectives on the neurobiology of drug addiction: a focus on genetics and factors regulating gene expression

Drug addiction is a chronic, relapsing disorder defined by cyclic patterns of compulsive drug seeking and taking interspersed with episodes of abstinence. While genetic variability may increase the risk of addictive behaviours in an individual, exposure to a drug results in neuroadaptations in interconnected brain circuits which, in susceptible individuals, are believed to underlie the transition to, and maintenance of, an addicted state. These adaptations can occur at the cellular, molecular, or (epi)genetic level and are associated with synaptic plasticity and altered gene expression, the latter being mediated via both factors affecting translation (epigenetics) and transcription (non coding microRNAs) of the DNA or RNA itself. New advances using techniques such as optogenetics have the potential to increase our understanding of the microcircuitry mediating addictive behaviours. However, the processes leading to addiction are complex and multifactorial and thus we face a major contemporary challenge to elucidate the factors implicated in the development and maintenance of an addicted state.

Glass shape influences consumption rate for alcoholic beverages

BACKGROUND

High levels of alcohol consumption and increases in heavy episodic drinking (binge drinking) are a growing public concern, due to their association with increased risk of personal and societal harm. Alcohol consumption has been shown to be sensitive to factors such as price and availability. The aim of this study was to explore the influence of glass shape on the rate of consumption of alcoholic and non-alcoholic beverages.

METHODS

This was an experimental design with beverage (lager, soft drink), glass (straight, curved) and quantity (6 fl oz, 12 fl oz) as between-subjects factors. Social male and female alcohol consumers (n = 159) attended two experimental sessions, and were randomised to drink either lager or a soft drink from either a curved or straight-sided glass, and complete a computerised task identifying perceived midpoint of the two glasses (order counterbalanced). Ethical approval was granted by the Faculty of Science Research Ethics Committee at the University of Bristol. The primary outcome measures were total drinking time of an alcoholic or non-alcoholic beverage, and perceptual judgement of the half-way point of a straight and curved glass.

RESULTS

Participants were 60% slower to consume an alcoholic beverage from a straight glass compared to a curved glass. This effect was only observed for a full glass and not a half-full glass, and was not observed for a non-alcoholic beverage. Participants also misjudged the half-way point of a curved glass to a greater degree than that of a straight glass, and there was a trend towards a positive association between the degree of error and total drinking time.

CONCLUSIONS

Glass shape appears to influence the rate of drinking of alcoholic beverages. This may represent a modifiable target for public health interventions.