Effects of 0.4 g/kg alcohol on attentional bias and alcohol-seeking behaviour in heavy and moderate social drinkers

Exploring Attentional Bias toward Alcohol Content: Insights from Eye-Movement Activity

INTRODUCTION

Attentional bias (AB) is an implicit selective attention toward processing disorder-significant information while neglecting other environmental cues. Considerable empirical evidence highlights the clinical implication of AB in the onset and maintenance of substance use disorder. An innovative method to explore direct measures of AB relies on the eye-movement activity using technologies like eye-tracking (ET). Despite the growing interest regarding the clinical relevance of AB in the spectrum of alcohol consumption, more research is needed to fully determine the AB patterns and its transfer from experimental to clinical applications. The current study consisted of three consecutive experiments. The first experiment aimed to design an ad-hoc visual attention task (VAT) consisting of alcohol-related and neutral images using a nonclinical sample (n = 15). The objective of the second and third experiments was to analyze whether the effect of type of image (alcohol-related vs. neutral images) on AB toward alcohol content using the VAT developed in the first experiment was different for type of drinker (light vs. heavy drinker in the second experiment [n = 30], and occasional social drinkers versus alcohol use disorder (AUD) patients in the third experiment [n = 48]).

METHODS

Areas of interest (AOIs) within each type of image (neutral and alcohol-related) were designed and raw ET-based data were subsequently extracted through specific software analyses. For experiment 1, attention maps were created and processed for each image. For experiments 2 and 3, data on ET variables were gathered and subsequently analyzed through a two-way ANOVA with the aim of examining the effects of the type of image and drinker on eye-movement activity.

RESULTS

There was a statistically significant interaction effect between type of image and type of drinker (light vs. heavy drinker in experiment 2, F(1, 56) = 13.578, p < 0.001, partial η2 = 0.195, and occasional social drinker versus AUD patients in the experiment 3, F(1, 92) = 35.806, p < 0.001, partial η2 = 0.280) for "first fixation" with large effect sizes, but not for "number of fixations" and "dwell time." The simple main effect of type of image on mean "first fixation" score for AUD patients was not statistically significant.

CONCLUSION

The data derived from the experiments indicated the importance of AB in sub-clinical populations: heavy drinkers displayed an implicit preference for alcohol-related images compared to light drinkers. Nevertheless, AB fluctuations in patients with AUD compared to the control group were found. AUD patients displayed an early interest in alcohol images, followed by an avoidance attentional processing of alcohol-related images. The results are discussed in light of recent literature in the field.

The impact of alcohol priming on craving and motivation to drink: a meta-analysis

BACKGROUND AND AIMS

An initial dose of alcohol can motivate-or prime-further drinking and may precipitate (re)lapse and bingeing. Lab-based studies have investigated the alcohol priming effect; however, heterogeneity in designs has resulted in some inconsistent findings. The aims of this meta-analysis were to (i) determine the pooled effect size for motivation to drink following priming, measured by alcohol consumption and craving, and (ii) examine whether design characteristics influenced any priming effect.

METHODS

Literature searches of PsycINFO, PubMed and Scopus in October 2020 (updated October 2021) identified lab-based alcohol priming studies that assessed effect of priming on motivation to drink. A tailored risk-of-bias tool assessed quality of lab-based studies. Random effects meta-analyses were computed on outcome data from 38 studies comparing the effect of a priming dose of alcohol against control on subsequent alcohol consumption/self-reported craving. Study characteristics that might have affected outcomes were design type (within/between-participant), dose of prime, time of motivation assessment, type of control drink (placebo alcohol/soft drink).

RESULTS

Relative to control, alcohol had a small-to-moderate priming effect on subsequent alcohol consumption (standardised mean difference [SMD] = 0.336 [95% CI, 0.171, 0.500]) and craving (SMD = 0.431 [95% CI, 0.306, 0.555]). Aspects of study design differentially affected consumption and craving. The size of the priming dose had no effect on consumption, but larger doses were sometimes associated with greater craving (with craving generally following the blood alcohol curve). Alcohol priming effects for consumption, but not craving, were smaller when compared with placebo, relative to soft drink, control.

CONCLUSIONS

Lab-based alcohol priming studies are a valid paradigm from which to investigate the impact of acute intoxication on alcohol motivation. Designs are needed that assess the impact of acute consumption on motivation to drink in more varied and realistic ways.

Attentional bias in alcohol drinkers: A systematic review of its link with consumption variables

In severe alcohol use disorder (SAUD), attentional bias refers to the preferential allocation of attentional resources toward alcohol-related cues. Dominant models consider that this bias plays a key role in the emergence and maintenance of SAUD. We evaluate the available experimental support for this assumption through a systematic literature review, providing a critical synthesis of studies exploring the links between alcohol consumption and attentional bias. Using PRISMA guidelines, we explored three databases (PsycINFO, PubMed, Scopus) and extracted 95 papers. We assessed their methodological quality and categorized them based on the population targeted, namely patients with SAUD or subclinical populations with various drinking patterns. We also classified papers according to the measures used (i.e., behavioral or eye-tracking measures). Overall, subclinical populations present an alcohol-related bias, but many studies in SAUD did not find such bias, nor approach/avoidance patterns. Moreover, attentional bias fluctuates alongside motivational states rather than according to alcohol use severity, which questions its stability. We provide recommendations to develop further theoretical knowledge and overcome methodological shortcomings.

How laboratory studies of cigarette craving can inform the experimental alcohol craving literature

Interest in alcohol and other drug craving has flourished over the past two decades, and evidence has accumulated showing that craving can be meaningfully linked to both drug use and relapse. Considerable human experimental alcohol craving research since 2000 has focused on craving as a clinical phenomenon. Self-reported craving to drink typically has served as a catch-all for the craving construct in these studies, whereas few studies have considered craving as a process (or hypothetical construct) that interacts with other phenomena to affect use. In contrast to alcohol, we believe that recently there has been more mechanistic work targeting cigarette craving-related processes. Here, we briefly present a narrative review of studies of acute alcohol craving in humans that have been conducted during the past two decades. We then specify important ways in which alcohol and tobacco differ (e.g., the role of withdrawal), and we note the unique challenges in inducing robust alcohol craving states in the laboratory. Finally, we offer recommendations for how the alcohol field might advance its conceptual understanding of craving by adopting ideas and methods drawn from the smoking research literature. Specifically, we suggest that researchers extend their studies to not only examine the link between alcohol craving and relapse but also to focus on why and, in some instances, how alcohol cravings matter clinically, and the circumstances under which craving especially matters. We propose research to investigate the shifts in alcohol-related cognitive and affective processing that occur during alcohol craving states. Furthermore, we highlight the value of research examining the level of insight that individuals with varying levels of alcohol involvement possess about their own craving-related processing shifts. We believe that laboratory studies can provide rich opportunities to examine conceptual questions about alcohol craving that are central to addiction.

Anti-saccade as a Tool to Evaluate Neurocognitive Impairment in Alcohol Use Disorder

It has been widely shown that chronic alcohol use leads to cognitive dysfunctions, especially inhibitory control. In an extension of the traditional approach, this research field has benefited from the emergence of innovative measures, among which is an anti-saccade, allowing direct and sensitive measure of the eye movements indexing attention bias to alcohol-related cues and the capability of inhibiting the reflexive saccades to the cues. During the past decade, there are numerous reports showing that drinkers make more unwanted reflexive saccades and longer latency in the anti-saccade task. These increased errors are usually explained by the deficits in inhibitory control. It has been demonstrated that inhibitory control on eye movement may be one of the earliest biomarkers of the onset of alcohol-related cognitive impairments. This review summarizes how an anti-saccade task can be used as a tool to investigate and assess the cognitive dysfunctions and the early detection of relapsing risk of alcohol dependence.

Intoxication without anticipation: Disentangling pharmacological from expected effects of alcohol

BACKGROUND

The pharmacological effects of alcohol on executive function, craving and subsequent alcohol-seeking have been well documented. Yet, insufficient methodological controls within existing alcohol administration paradigms have meant that the relative importance of alcohol's pharmacological and anticipatory effects remains in need of further elucidation.

AIM

The objective of this study is to disentangle alcohol's pharmacological effects from its anticipatory effects on alcohol-related cognitions and subsequent consumption.

METHODS

Inhibitory control, attentional bias and craving were assessed pre- and post-consumption in 100 participants who were randomly allocated to one of four beverage conditions in a two by two design: (1) alcohol aware (alcohol with participant knowledge (pharmacological/anticipation effects)), (2) alcohol blind (alcohol without participant knowledge; in a novel grain alcohol masking condition (pharmacological/no anticipation effects)), (3) placebo (no alcohol but participants were deceived (anticipation/non-pharmacological effects)) and (4) pure control (no alcohol with participant knowledge (no anticipation/non-pharmacological effects)).

RESULTS

Findings suggest that the pharmacological effects of alcohol result in greater inhibitory control impairments compared with anticipated effects. Anticipatory but not the pharmacological effects of alcohol were found to increase attentional bias. Both pharmacology and anticipation resulted in increased craving, though higher levels of craving were observed due to alcohol's pharmacology. Furthermore, alcohol pharmacology resulted in heightened ad libitum consumption; however, anticipation did not. Changes in craving partially mediated the relationship between initial intoxication and subsequent drinking, while inhibitory control impairments did not.

CONCLUSIONS

Successive alcohol consumption appears driven primarily by the pharmacological effects of alcohol which are exerted via changes in craving.

The Effects of Placebo and Moderate Dose Alcohol on Attentional Bias, Inhibitory Control and Subjective Craving

AIMS

Previous research indicates that acute alcohol intoxication and placebo can inhibit people's control over consumption behaviour and heighten attentional bias (AB) towards alcohol-related stimuli and craving. We designed a study to disentangle anticipated from pharmacological effects of alcohol in order to gain a clearer view of their relative contributions to alcohol consumption.

METHODS

In a within-participants design (moderate alcohol dose, placebo and control), and over a minimum 2-week period, participants completed a battery of questionnaires and cognitive tasks, followed by a bogus taste task to measure ad libitum consumption.

RESULTS

Both alcohol preload and placebo resulted in cognitive and psychological changes, including impaired inhibitory control, heightened AB and craving. However, ad libitum consumption only increased following alcohol and not placebo. Furthermore, inhibitory control impairments did not mediate the relationship between initial intoxication and ad libitum consumption, and findings indicate that increases in craving may mediate this association.

CONCLUSION

Psychological processes such as craving may be more important in driving consummatory behaviour relative to transient changes in cognitive processes, such as inhibitory control.

Alcohol-related attentional biases in recently detoxified inpatients with severe alcohol use disorder: an eye-tracking approach

BACKGROUND

Dominant theoretical models consider that attentional biases (AB) towards alcohol-related stimuli play a key role in the development and maintenance of alcohol use disorder (AUD). Their assessment has however showed high inconsistencies and has been mostly based on unreliable behavioral measures. This study evaluated the presence and extent of alcohol-related AB in recently detoxified inpatients with severe AUD by combining the visual probe task (VPT) paradigm with eye-tracking measures, known to improve the VPT reliability in subclinical populations.

METHODS

We recruited 24 patients and 27 matched healthy controls. They performed the VPT (measuring reaction time when processing visual targets preceded by alcoholic and matched non-alcoholic pictures) combined with eye-tracking measures (dwell time, first fixation direction/duration, second fixation direction) during two sessions. Estimates of internal consistency, split-half reliability, and test-retest reliability were measured.

RESULTS

Patients showed shorter dwell time for alcohol cues (p = .004, d=.853) and reduced number of fixations towards alcohol after a first fixation on non-alcohol cues (p = .012, d=.758) compared to controls. These findings suggest the presence of alcohol-related avoidance AB in detoxified patients with severe AUD. The VPT achieved excellent reliability for these eye-tracking measures. Reaction times and first fixation measures did not indicate any AB pattern and showed poor reliability.

CONCLUSIONS

The VPT, when combined with dwell time and second fixation direction, constitutes a reliable method for assessing AB in detoxified patients. It showed the presence of an alcohol-related avoidance bias in this clinical population, in contradiction with the approach bias predicted by theoretical models.

Does alcohol-related desire thinking predict in-the-moment drinking behaviours?

Desire thinking (voluntary thinking involving a perseverative focusing on desired target-related memories, images, and information), is an important factor in the experience of drinking urges and cravings. Research has not examined the relationship between desire thinking, behavioural intention and the implementation of that behaviour into action, nor how one's past repeated behaviour in situ (expressed as habit) may moderate these relationships. We employed an ad libitum drinking paradigm to provide indirect measures of in-the-moment drinking behaviours (amount poured [mls] and amount consumed [mls]) in a group of eighty-eight self-defined social drinkers immediately after measuring self-reported drinking habit, drinking-related desire thinking, and general drinking behaviour. Results confirmed the predicted positive relationship between desire thinking and in-the-moment drinking behaviour with the effects increasing as a function of rising drinking habit strength. We also observed a dissociation between desire thinking components (verbal perseveration and imaginal prefiguration) in the moderating effects of habit strength on drinking behaviour. For imaginal prefiguration (thoughts related to construction of mental images of a desired target or of its context for consumption) a direct effect on drinking behaviours was shown. In comparison, the effect for verbal perseveration (repetitive self-talk regarding the need to achieve a desired target) was not shown to independently predict drinking-related behaviour but was significantly moderated by increasing drinking-related habit strength. Future work should formulate the nature of this moderating influence on perseverative goal-directed thinking.

A review of studies exploring fetal alcohol spectrum disorders through eye tracking measures

The widespread cognitive and cerebral consequences of prenatal alcohol exposure have been established during the last decades, through the exploration of fetal alcohol spectrum disorders (FASD) using neuropsychological and neuroscience tools. This research field has recently benefited from the emergence of innovative measures, among which eye tracking, allowing a precise measure of the eye movements indexing a large range of cognitive functions. We propose a comprehensive review, based on PRISMA guidelines, of the eye tracking studies performed in populations with FASD. Studies were selected from the PsycINFO, PubMed and Scopus databases, and were evaluated through a standardized methodological quality assessment. Studies were classified according to the eye tracking indexes recorded (saccade characteristics, initial fixation, number of fixations, dwell time, gaze pattern) and the process measured (perception, memory, executive functions). Eye tracking data showed that FASD are mostly associated with impaired ocular perceptive/motor abilities (i.e., altered eye movements, centrally for saccade initiation), lower accuracy as well as increased error rates in saccadic eye movements involving working memory abilities, and reduced inhibitory control on saccades. After identifying the main limitations presented by the reviewed studies, we propose guidelines for future research, underlining the need to increase the standardization of diagnosis and evaluation tools, and to improve the methodological quality of eye tracking measures.

Eye Tracking Studies Exploring Cognitive and Affective Processes among Alcohol Drinkers: a Systematic Review and Perspectives

Acute alcohol intoxication and alcohol use disorders are characterized by a wide range of psychological and cerebral impairments, which have been widely explored using neuropsychological and neuroscientific techniques. Eye tracking has recently emerged as an innovative tool to renew this exploration, as eye movements offer complementary information on the processes underlying perceptive, attentional, memory or executive abilities. Building on this, the present systematic and critical literature review provides a comprehensive overview of eye tracking studies exploring cognitive and affective processes among alcohol drinkers. Using PRISMA guidelines, 36 papers that measured eye movements among alcohol drinkers were extracted from three databases (PsycINFO, PubMed, Scopus). They were assessed for methodological quality using a standardized procedure, and categorized based on the main cognitive function measured, namely perceptive abilities, attentional bias, executive function, emotion and prevention/intervention. Eye tracking indexes showed that alcohol-related disorders are related to: (1) a stable pattern of basic eye movement impairments, particularly during alcohol intoxication; (2) a robust attentional bias, indexed by increased dwell times for alcohol-related stimuli; (3) a reduced inhibitory control on saccadic movements; (4) an increased pupillary reactivity to visual stimuli, regardless of their emotional content; (5) a limited visual attention to prevention messages. Perspectives for future research are proposed, notably encouraging the exploration of eye movements in severe alcohol use disorders and the establishment of methodological gold standards for eye tracking measures in this field.

Where's the wine? Heavy social drinkers show attentional bias towards alcohol in a visual conjunction search task

BACKGROUND AND AIMS

Research indicates that high consumers of alcohol exhibit attentional bias (AB) towards alcohol-related cues, suggestive of a cognitive mechanism that might drive substance seeking. Many tasks that measure AB (e.g. visual probe, addiction Stroop), however, are limited by their reliance on non-appetitive control cues, the serial presentation of stimuli and their poor internal reliability. The current study employed a visual conjunction search (VCS) task capable of presenting multiple alcoholic and non-alcoholic appetitive cues simultaneously to assess whether social drinkers attend selectively to alcoholic stimuli. To assess the construct validity of this task, we examined whether alcohol consumption and related problems, subjective craving and drinking motives predict alcohol-specific AB.

DESIGN AND SETTING

A VCS task was performed in a laboratory setting, which required participants to detect the presence of appetitive alcoholic (wine, beer) and non-alcoholic (cola, lemonade) targets within arrays of matching and non-matching distractors.

PARTICIPANTS

Data from 99 participants were assessed [mean_age  = 20.77, standard deviation (SD) = 2.98; 64 (65%) females], with 81.8% meeting the threshold for harmful alcohol consumption (mean_AUDIT  = 12.89, SD = 5.79).

MEASUREMENTS

Self-reports of alcohol consumption and related problems [Alcohol Use Disorders Identification Test (AUDIT)], subjective craving (Alcohol Craving Questionnaire Short Form) and drinking motives (Drinking Motives Questionnaire Short Form) were obtained, and the VCS task measured response times for the correct detection of alcoholic and non-alcoholic targets.

FINDINGS

Participants were significantly quicker to detect alcoholic relative to non-alcoholic appetitive targets (P < 0.001, d_z  = 0.41), which was predicted positively by AUDIT scores (P = 0.013, R²  = 0.06%). The VCS task achieved excellent reliability (α > 0.79), superior to other paradigms.

CONCLUSIONS

The visual conjunction search task appears to be a highly reliable method for assessing alcohol-related attentional bias, and shows that heavy social drinkers prioritize alcoholic cues in their immediate environment.

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.

Does Self-Reported or Behavioral Impulsivity Predict Subjective Response to Low-Dose Alcohol?

AIMS

Subjective response to alcohol and impulsivity are both independent predictors of alcohol use and may be related risk factors for alcohol use disorders (AUDs). Recent findings suggest that more impulsive individuals may experience higher risk subjective response patterns at moderate-to-high doses of alcohol. However, whether these relationships are observable early in a drinking occasion remains an open question. This study examined multiple measures of impulsivity in relation to subjective response following low-dose alcohol.

METHOD

Eighty-seven non-treatment-seeking heavy drinkers were enrolled in a placebo-controlled alcohol administration study testing the effects of NMDA receptor antagonist, Memantine. Baseline impulsivity assessments included the Cued Go/No-Go Task, Experiential Discounting Task, and Barratt Impulsiveness Scale, Version 11 (BIS-11). Following consumption of low-dose alcohol aimed to increase blood alcohol concentration (BAC) to 0.03%, subjective stimulation and sedation were measured using the Biphasic Alcohol Effects Scale. Models were tested to relate impulsivity measures to subjective response with a post hoc exploratory model exploring boredom as an alternate predictor.

RESULTS

Increases in stimulation and sedation were observed following low-dose alcohol, but were not predicted significantly by impulsivity measures. Although greater impulsivity on the BIS-11 was a trend-level predictor of increased sedation, post hoc analyses suggested these results were an artifact of boredom.

CONCLUSION

Although impulsivity did not predict subjective response to low-dose alcohol, the results suggest that small amounts of alcohol can produce a range of subjective effects, even among heavy drinkers. Future studies would benefit by examining subjective response across a range of BACs among both light and heavy drinkers.

Beer? Over here! Examining attentional bias towards alcoholic and appetitive stimuli in a visual search eye-tracking task

RATIONALE

Experimental tasks that demonstrate alcohol-related attentional bias typically expose participants to single-stimulus targets (e.g. addiction Stroop, visual probe, anti-saccade task), which may not correspond fully with real-world contexts where alcoholic and non-alcoholic cues simultaneously compete for attention. Moreover, alcoholic stimuli are rarely matched to other appetitive non-alcoholic stimuli.

OBJECTIVES

To address these limitations by utilising a conjunction search eye-tracking task and matched stimuli to examine alcohol-related attentional bias.

METHODS

Thirty social drinkers (Mage = 19.87, SD = 1.74) were asked to detect whether alcoholic (beer), non-alcoholic (water) or non-appetitive (detergent) targets were present or absent amongst a visual array of matching and non-matching distractors. Both behavioural response times and eye-movement dwell time were measured.

RESULTS

Social drinkers were significantly quicker to detect alcoholic and non-alcoholic appetitive targets relative to non-appetitive targets in an array of matching and mismatching distractors. Similarly, proportional dwell time was lower for both alcoholic and non-alcoholic appetitive distractors relative to non-appetitive distractors, suggesting that appetitive targets were relatively easier to detect.

CONCLUSIONS

Social drinkers may exhibit generalised attentional bias towards alcoholic and non-alcoholic appetitive cues. This adds to emergent research suggesting that the mechanisms driving these individual's attention towards alcoholic cues might 'spill over' to other appetitive cues, possibly due to associative learning.

The effects of reward and loss anticipation on attentional bias for reward-related stimuli

Attentional biases for reward-related (e.g., food, alcohol) cues are moderated by the expectation of imminent reward availability, but the psychological mechanisms that underlie this effect are unclear. We report two studies in which we investigated if effects of reward gain anticipation are specific to the type of reward that is anticipated, and if anticipation of loss has comparable effects to anticipation of reward gain. We used an eye tracking task to investigate the effects of anticipation of gain (experiment 1) or loss (experiment 2) of alcohol and chocolate on attentional bias for alcohol and chocolate pictures using full crossover designs; the effects of uncertain outcomes were investigated in both experiments. Results indicated robust effects of anticipation of reward gain and uncertainty on attentional bias that were outcome-specific (experiment 1). However attentional bias was not influenced by loss anticipation (experiment 2). Our findings demonstrate that anticipation of reward gain increases attentional bias for the type of reward that is anticipated, but anticipation of loss does not influence attentional bias.

The effect of beliefs about alcohol's acute effects on alcohol priming and alcohol-induced impairments of inhibitory control

Acute alcohol administration can lead to a loss of control over drinking. Several models argue that this 'alcohol priming effect' is mediated by the effect of alcohol on inhibitory control. Alternatively, beliefs about how alcohol affects behavioural regulation may also underlie alcohol priming and alcohol-induced inhibitory impairments. Here two studies examine the extent to which the alcohol priming effect and inhibitory impairments are moderated by beliefs regarding the effects of alcohol on the ability to control behaviour. In study 1, following a priming drink (placebo or .5g/kg of alcohol), participants were provided with bogus feedback regarding their performance on a measure of inhibitory control (stop-signal task; SST) suggesting that they had high or average self-control. However, the bogus feedback manipulation was not successful. In study 2, before a SST, participants were exposed to a neutral or experimental message suggesting acute doses of alcohol reduce the urge to drink and consumed a priming drink and this manipulation was successful. In both studies craving was assessed throughout and a bogus taste test which measured ad libitum drinking was completed. Results suggest no effect of beliefs on craving or ad lib consumption within either study. However, within study 2, participants exposed to the experimental message displayed evidence of alcohol-induced impairments of inhibitory control, while those exposed to the neutral message did not. These findings do not suggest beliefs about the effects of alcohol moderate the alcohol priming effect but do suggest beliefs may, in part, underlie the effect of alcohol on inhibitory control.

Changes in the Relative Balance of Approach and Avoidance Inclinations to Use Alcohol Following Cue Exposure Vary in Low and High Risk Drinkers

According to the ambivalence model of craving, alcohol craving involves the dynamic interplay of separate approach and avoidance inclinations. Cue-elicited increases in approach inclinations are posited to be more likely to result in alcohol consumption and risky drinking behaviors only if unimpeded by restraint inclinations. Current study aims were (1) to test if changes in the net balance between approach and avoidance inclinations following alcohol cue exposure differentiate between low and high risk drinkers, and (2) if this balance is associated with alcohol consumption on a subsequent taste test. In two experiments (N = 60; N = 79), low and high risk social drinkers were exposed to alcohol cues, and pre- and post- approach and avoidance inclinations measured. An ad libitum alcohol consumption paradigm and a non-alcohol exposure condition were also included in Study 2. Cue-elicited craving was characterized by a predominant approach inclination only in the high risk drinkers. Conversely, approach inclinations were adaptively balanced by equally strong avoidance inclinations when cue-elicited craving was induced in low risk drinkers. For these low risk drinkers with the balanced craving profile, neither approach or avoidance inclinations predicted subsequent alcohol consumption levels during the taste test. Conversely, for high risk drinkers, where the approach inclination predominated, each inclination synergistically predicted subsequent drinking levels during the taste test. In conclusion, results support the importance of assessing both approach and avoidance inclinations, and their relative balance following alcohol cue exposure. Specifically, this more comprehensive assessment reveals changes in craving profiles that are not apparent from examining changes in approach inclinations alone, and it is this shift in the net balance that distinguishes high from low risk drinkers.

Bibi ergo sum: the effects of a placebo and contextual alcohol cues on motivation to drink alcohol

RATIONALE

Acute 'priming' doses of alcohol reliably increase alcohol-seeking behaviour in social drinkers. However, the effects of the anticipated (rather than pharmacological) effects of alcohol, and their interaction with contextual alcohol cues, are not well understood.

OBJECTIVES

This study aims to determine the extent to which an alcohol-placebo drink increases craving, subjective intoxication and beer consumption, while conjointly investigating the impact of contextual alcohol cues.

METHODS

On a within-subject basis, 64 undergraduate social drinkers consumed both a placebo (which they believed to contain alcohol) and a control drink (which they knew did not contain alcohol) in different sessions. Participants completed the study procedures in a bar laboratory designed to look like a 'pub' or a standard psychology lab containing no alcohol-related cues. Craving (Desires for Alcohol Questionnaire) and subjective intoxication were measured pre- and post-drink, and a bogus taste test to measure ad-lib alcohol consumption was completed at the end of each session.

RESULTS

Compared to the control drink, placebo significantly increased craving, ad-lib consumption and subjective intoxication, regardless of environmental context.

CONCLUSIONS

Increased craving and ad-lib alcohol consumption after consuming a priming dose of alcohol is at least partly attributable to the anticipated rather than the pharmacological effects of the priming dose.

Alcohol Administration Increases Cocaine Craving But Not Cocaine Cue Attentional Bias

BACKGROUND

Alcohol consumption is a known antecedent to cocaine relapse. Through associative conditioning, it is hypothesized that alcohol increases incentive motivation for cocaine and thus the salience of cocaine-related cues, which are important in maintaining drug-taking behavior. Cocaine-using individuals display a robust cocaine cue attentional bias as measured by fixation time during the visual probe task. The purpose of this study was to evaluate the influence of alcohol administration on cocaine cue attentional bias using eye-tracking technology to directly measure attentional allocation.

METHODS

Twenty current cocaine users completed a double-blind, placebo-controlled, within-subjects study that tested the effect of 3 doses of alcohol (0.00, 0.325, and 0.65 g/kg) on cocaine cue attentional bias using the visual probe task with eye-tracking technology. The participant-rated and physiological effects of alcohol were also assessed.

RESULTS

Participants displayed a robust cocaine cue attentional bias following both placebo and alcohol administration as measured by fixation time, but not response time. Alcohol administration did not influence cocaine cue attentional bias, but increased craving for cocaine in a dose-dependent manner. Alcohol produced prototypic psychomotor and participant-rated effects.

CONCLUSIONS

Alcohol administration increases cocaine craving but not cocaine cue attentional bias. Alcohol-induced cocaine craving suggests that alcohol increases incentive motivation for cocaine but not the salience of cocaine-related cues.

Brain Activation Associated with Automatic Processing of Alcohol-Related Cues in Young Heavy Drinkers and Its Modulation by Alcohol Administration

BACKGROUND

While the automatic processing of alcohol-related cues by alcohol abusers is well established in experimental psychopathology approaches, the cerebral regions involved in this phenomenon and the influence of alcohol intake on this process remain unknown. The aim of this functional magnetic resonance imaging (fMRI) study was to investigate the neural mechanisms underlying the processing of task-irrelevant alcohol-related stimuli in young heavy drinkers and their modulation by alcohol administration.

METHODS

Twelve heavy drinking male participants were scanned on 2 separate days; once after a low dose of alcohol intake (0.4 g/kg), and once after a placebo intake, in balanced order. Images of alcoholic drinks, soft drinks, or neutral objects were shown while participants' neural activity was recorded through fMRI. Moreover, participants' attentional focus was manipulated using a task which required them to process the central images of interest (focus alcohol condition) or a center unattended task (focus not on alcohol condition).

RESULTS

Results indicated that an explicit judgment on beverage-related cues increased activation in the prefrontal area compared with the judgment of neutral objects. By comparison with that of task-irrelevant neutral cues, the processing of task-irrelevant alcohol-related cues increased the activation in a large network of cerebral areas including visual and temporal regions, the bilateral anterior cingulate cortex, the posterior cingulate cortex, and the putamen. Moreover, in the condition with focus not on alcohol, the ventral tegmental area (VTA) was particularly activated by the presentation of (task-irrelevant) alcohol-related cues compared to task-irrelevant soft-drink-related cues.

CONCLUSIONS

The VTA was especially involved in the automatic processing of alcohol-related cues in young heavy drinkers. Low dose of alcohol did not modulate the neural substrates involved in the processing of salient alcohol-related cues.

Increased behavioral economic demand and craving for alcohol following a laboratory alcohol challenge

BACKGROUND AND AIMS

Although increases in subjective alcohol craving have been observed following moderate doses of alcohol (e.g. priming effects), the effects of alcohol consumption on behavioral economic demand for alcohol are largely unstudied. This study examined the effects of alcohol intoxication on alcohol demand and craving.

DESIGN

A between-subjects design in which participants were randomly assigned to either an alcohol (n = 31), placebo (n = 29) or control (n = 25) condition.

SETTING

A laboratory setting at the University of Missouri, USA.

PARTICIPANTS

Eighty-five young adult moderate drinkers were recruited from the University of Missouri and surrounding community.

MEASUREMENTS

Change in demand for alcohol across time was measured using three single items: alcohol consumption at no cost (i.e. intensity), maximum price paid for a single drink (i.e. breakpoint) and total amount spent on alcohol (i.e. Omax). Alcohol demand at baseline was also assessed using an alcohol purchase task (APT). Craving was assessed using a single visual analog scale item.

FINDINGS

In the alcohol group compared with the combined non-alcohol groups, intensity, breakpoint and craving increased from baseline to the ascending limb and decreased thereafter (Ps < 0.05; Omax , P = 0.06). Change in craving following alcohol consumption was significantly associated with change in each of the demand indices (Ps < 0.0001). Finally, the demand single items were associated with corresponding indices from the APT (Ps < 0.05).

CONCLUSIONS

Alcohol demand increases following intoxication, in terms of both the maximum amount people are willing to pay for one drink and the number of drinks people would consume if drinks were free. Behavioral economic measures of alcohol value can complement subjective craving as measures of moment-to-moment fluctuations in drinking motivation following intoxication.

The clinical relevance of attentional bias in substance use disorders

Individuals with substance use disorders typically show an "attentional bias" for substance-related cues: Those cues are able to grab and hold the attention, in preference to other cues in the environment. We discuss the theoretical context for this work before reviewing the measurement of attentional bias, and its relationship to motivational state and relapse to substance use after a period of abstinence. Finally, we discuss the implications of this research for the treatment of substance use disorders. We conclude that attentional bias is associated with subjective craving, and that moment-by-moment fluctuations in attentional bias may precede relapse to substance use. The evidence regarding the predictive relationship between attentional bias assessed in treatment contexts and subsequent relapse is inconsistent. Furthermore, there is currently insufficient evidence to endorse attentional bias modification as a treatment for substance use disorders. Clinical implications and suggestions for future research are highlighted.

Relationship between alcohol dependence, escape drinking, and early neural attention to alcohol-related cues

RATIONALE

Previous work has indicated that implicit attentional biases to alcohol-related cues are indicative of susceptibility to alcohol dependence and escape drinking, or drinking to avoid dysphoric mood or emotions.

OBJECTIVE

The goal of the current study was to examine whether alcohol dependence and escape drinking were associated with early neural attentional biases to alcohol cues.

METHODS

Electroencephalography data were recorded from 54 college students who reported that they regularly drank alcohol, while they viewed alcohol and control pictures that contained human content (active) or no human content (inactive).

RESULTS

Those who were alcohol dependent showed more neural attentional bias to the active alcohol-related stimuli than to the matched control stimuli early in processing, as indicated by N1 amplitude. Escape drinkers showed greater neural attention to the active alcohol cues than non-escape drinkers, as measured by larger N2 amplitudes.

CONCLUSIONS

While alcohol dependence is associated with enhanced automatic attentional biases early in processing, escape drinking is associated with more controlled attentional biases to active alcohol cues during a relatively later stage in processing. These findings reveal important information about the time-course of attentional processing in problem drinkers and have important implications for addiction models and treatment.

A comparison of the anticipated and pharmacological effects of alcohol on cognitive bias, executive function, craving and ad-lib drinking

Acute alcohol administration alters automatic processing of alcohol-related cues, impairs executive functions and increases alcohol seeking. Few studies have investigated the effects of expecting to receive alcohol on these measures. Thirty-one social drinkers completed three experimental sessions receiving either 0.65 g/kg alcohol, a placebo and a control beverage (which they knew was not alcoholic) before reporting craving and completing a test battery including a measure of automatic alcohol-approach tendencies (stimulus response compatibility task), a measure of executive function (Controlled Oral Word Association Task (COWAT)) and a taste test assessing ad-lib drinking. Results indicated that alcohol administration impaired performance on the COWAT and increased ad-lib drinking; however, there were no significant differences on these measures after administration of placebo versus control beverages. Craving was increased after alcohol and (to a lesser extent) after placebo. Automatic alcohol-approach tendencies were pronounced after both alcohol and placebo compared to the control beverage, with no difference between alcohol and placebo. Results suggest craving is sensitive to the anticipated and pharmacological effects of alcohol, alcohol-approach tendencies are particularly sensitive to the anticipated effects of alcohol, and measures of executive function and ad-lib drinking are affected by the pharmacological, but not the anticipated, effects of alcohol.