Alcohol effects on interoception shape expectancies and subjective effects: a registered report using the heart rate discrimination task.

AIMS: Alcohol acutely impacts interoceptive processes, which in turn affect the perception of alcohol effects and the development of alcohol expectancies. However, previous research is limited by the tools used to measure cardiac interoception and subjective alcohol effects. This registered report proposes a re-examination of previous findings using a state-of-the-art measure of interoceptive capacity, the heart rate discrimination task, and measurements of subjective alcohol effects across both ascending and descending limbs. METHODS: In a double-blind, placebo-controlled experiment, n = 36 participants were given 0.4 g/kg of ethanol, and a baseline measure of alcohol expectancies was obtained. Changes in interoceptive capacity after beverage administration, along with measures of light-headedness, mood, and biphasic alcohol effects, were assessed over two sessions. HYPOTHESES: As registered in this secondary data analysis, alcohol was expected to acutely impact different indices of interoceptive capacity, and those changes were hypothesized to correlate with subjective alcohol effects and expectancies. Analyses were conducted only following in-principle acceptance. RESULTS: Alcohol-induced changes in interoceptive capacity predicted the development of light-headedness, stimulation, and negative mood. Changes in interoceptive capacity were also correlated with negative alcohol expectancies, as measured 2 weeks prior to the experiment. These effects were unique to the interoceptive condition, as null effects were observed in an exteroceptive control task. DISCUSSION: This report offers a replication of key previous findings that alcohol impacts interoceptive processes to shape the detection of subjective alcohol effects. We propose that, through repeated drinking occasions, bodily responses feed into the experience of intoxication, shaping future expectancies about alcohol effects.

A systematic review of the acute effects of alcohol on emotion recognition of facial expressions.

Alcohol has been linked to both positive (e.g., sociability) and negative (e.g., aggression) social outcomes, and researchers have proposed that alcohol-induced changes in emotion recognition may partially explain these effects. Here, we systematically review alcohol administration studies to clarify the acute effects of alcohol on emotion recognition. We also investigate various moderator variables (i.e., sex, study quality, study design, alcohol dosage, emotion recognition task and outcome measure). PsycINFO, PubMed and Google Scholar were searched following a pre-registered PROSPERO protocol (CRD42021225392) and PRISMA methodology. Analyses focused on differences in emotion recognition between participants consuming alcoholic and/or non-alcoholic (i.e., placebo or no-alcohol control) beverages. Nineteen unique samples (N = 1271 participants) were derived from 17 articles (two articles included two studies, each conducted on a unique sample). Data were extracted for sample characteristics, alcohol administration methods and emotion recognition tasks and outcomes. All studies compared an alcoholic beverage to a placebo beverage and used tasks that asked participants to identify emotions from images or videos of facial expressions. Otherwise, methodologies varied substantially across studies, including the alcohol dosage(s) tested, the specific emotion recognition task(s) used and the outcome variable(s) assessed. No consistent effects of alcohol on emotion recognition emerged for any emotion. None of the moderator variables affected the findings, except for some indication that alcohol may affect males' emotion recognition abilities more so than females. Alcohol does not appear to consistently affect positive or negative emotion recognition of facial expressions, at least with the tasks currently used in the field.

Changes in interoception after alcohol administration correlate with expectancies and subjective effects.

Interoceptive signals give rise to subjective feeling states that can drive motivational and behavioural responses. In the context of alcohol use behaviours, interoceptive signals may shape subjective alcohol experiences and thereby support biobehavioural mechanisms of drinking behaviour change. This study examined the acute effects of alcohol on participants' interoceptive abilities and determined whether pharmacologically induced changes in heart beat detection correlate with subjective alcohol effects, craving and expectancies. Participants completed a two-session, double-blind placebo controlled experiment (n = 27). Participants consumed a beverage containing 0.4 g/kg of alcohol or a placebo. They also completed measurements of alcohol expectancies at baseline, and alcohol-induced changes in mood, craving and light-headedness. Interoceptive ability was measured using the heartbeat discrimination task prior to and following beverage administration, yielding indices of interoceptive accuracy, confidence and meta-cognition. Alcohol administration increased interoceptive accuracy compared with baseline and placebo; and those changes in interoception negatively correlated with negative alcohol expectancies. Further, changes in interoception positively correlated with perceived light-headedness and positive mood after alcohol administration, whereas null effects were found for craving. In the placebo condition, null results were obtained. Alcohol is well established to change bodily states, and here, we find that the extent to which alcohol increases participants' sensitivity to bodily states correlates with their subjective drinking experiences. This was observed in relation to mood, light-headedness and prospective alcohol expectancies. We posit that over successive alcohol experiences, changes in bodily states may feed into the development of alcohol expectancies that could in turn predict future drinking behaviours.

A Critical Review of Alcohol Administration Guidelines in Laboratory Medication Screening Research: Is It Time to Include Treatment Seekers?

Human laboratory studies play an important role in alcohol use disorder (AUD) medication development. Medications that are found to be safe and effective during human laboratory screening will then move to more expensive clinical trials in patient populations. Given the gatekeeping role of human laboratory studies in the medication development pipeline, it is critical that these studies accurately forecast how pharmacotherapies will perform under true-to-life clinical conditions. On the other hand, the design of these studies also must adhere to ethical guidelines: certain aspects of clinical reality cannot be incorporated into screening studies because doing so might place the participant at risk for harm or breach other ethical guidelines. Conventions exist that guide the resolution of these conflicting ideals. This article considers the practice of recruiting non-treatment-seeking heavy drinkers to participate in laboratory screening studies. By convention, volunteers are excluded from laboratory screening studies that involve alcohol administration if they are deemed "treatment seeking," meaning that they recently stopped drinking or are motivated to do so. Although this common practice may reduce risk to participants, findings may not accurately predict medication effects on treatment seekers. Indeed, there is empirical evidence that treatment seekers differ from nontreatment seekers in their responses to medications (Neuropsychopharmacology 2017a; 42: 1776; Am J Drug Alcohol Abuse 2017b; 43: 703; J Psychiatr Res 2006; 40: 383). Here, we argue for the importance of recruiting treatment seekers for this research due to their qualitative difference from nontreatment seekers. We argue that these individuals should be the default population in human laboratory medication screening studies. We conclude by discussing 2 case examples of medication experiments led by our research groups that involved administering medications to treatment seekers.

How Alcohol Influences Mechanisms of Sexual Risk Behavior Change: Contributions of Alcohol Challenge Research to the Development of HIV Prevention Interventions.

This paper examines the contributions of laboratory-based alcohol challenge research (ACR) to the development of HIV prevention interventions. Following a brief overview of HIV prevention interventions and related health behavior change models, we discuss how alcohol may influence mechanisms of behavior change. The paper highlights the value of ACR for: (1) elucidating mechanisms of action through which alcohol affects sexual risk behavior, (2) testing how alcohol may influence mechanisms thought to underlie HIV prevention interventions, (3) clarifying moderators of the causal influences of alcohol, (4) identifying novel intervention targets, and (5) developing strategies to reduce sexual risk among those who consume alcohol. We conclude with a discussion of the importance of using experimental research to identify mechanisms of behavior change that are specific to populations at high risk for HIV and outline some key implications for developing HIV prevention interventions that integrate the role of alcohol.

Interoceptive signaling in alcohol cognitive biases: Role of family history and alliesthetic components.

The role of interoceptive signals in the development of cognitive biases for drug-related cues has been hypothesized in the past; however, experimental evidence is lacking. This report examined the relationship between physiological responses and memories for alcohol cues. Participants (n = 158) were categorized as having either a positive or negative family history of alcohol use disorder (AUD). They were assigned to an alcohol, placebo, or control beverage condition to which they were blinded. All participants were presented with alcohol, neutral, and emotional cues. Heart rate variability (HRV) at 0.1 Hz, as an index of viscero-afferent reactivity, and in the high-frequency range was measured during picture-cue exposure. Participants then completed free recall and repetition priming tasks to assess memories for previously presented stimuli. Participants with a positive family history (FHP) for AUD who received an alcohol beverage displayed a positive relationship between 0.1 Hz HRV and free recall. This effect was specific to alcohol cues, highlighting the relevance of physiological signals in the development of alcohol cognitive biases. These results support the hypothesis of a coordinated brain-body interaction in the development of drug-related behaviors. FHP as an AUD risk factor may increase the mapping of physiological responses onto cognitive biases for alcohol cues. Increased ratings of subjective intoxication dampened this relationship, suggesting that perceived bodily states may modulate incentive salience processes. This report provides novel evidence for the involvement of interoceptive signals in addictive processes, setting a precedent for the exploration of brain-body interactions in the study of alcohol cognitive biases.

Sexual Aggression Analogues Used in Alcohol Administration Research: Critical Review of Their Correspondence to Alcohol-Involved Sexual Assaults.

BACKGROUND: Alcohol administration studies are crucial because causal questions about alcohol's role in human behavior can only be answered through experimental research that randomly assigns participants to drink conditions. The primary goal of this review was to catalogue the characteristics of experimental analogues used in alcohol administration research to assess men's sexual aggression proclivity and evaluate the extent to which they represent the scope of alcohol-involved sexual aggression. Although this review focuses on sexual aggression analogues, the identified methodological issues are relevant to a wide range of alcohol administration studies. METHODS: Online databases were searched for published studies that randomly assigned participants to drink conditions and assessed participants' sexual aggression proclivity with an experimental analogue. Characteristics of the analogues were coded by both authors. RESULTS: Seventeen studies were identified that used 12 unique experimental analogues. All of the analogues depicted a completed or potential sexual assault in an apartment between a male perpetrator and female victim who did not know each other well. This information was presented in written (n = 7), audio (n = 1), video (n = 3), or virtual simulation (n = 1) format. Sexual aggression proclivity was measured through participants' self-reports (n = 10) and behavioral responses (n = 2). Perpetrators primarily used physical force which the woman verbally and physically resisted. Only one analogue depicted behavioral signs of the woman's alcohol impairment; none included signs of the man's alcohol impairment. CONCLUSIONS: These analogues were designed to address important theoretical questions; however, they do not represent the full range of alcohol-involved sexual assaults. This hampers the development of evidence-based prevention and treatment programs because we do not know whether these findings generalize to other types of sexual assaults (e.g., with incapacitated victims, within serious relationships, with sexual and other gender minorities). Funding agencies need to support more alcohol administration research in order to provide a strong foundation for the development of effective interventions.

The Feasibility, Tolerability, and Safety of Administering a Very High Alcohol Dose to Drinkers with Alcohol Use Disorder.

INTRODUCTION: There remains a paucity of research quantifying alcohol's effects in drinkers with alcohol use disorder (AUD), particularly responses to very high alcohol doses (≥0.8 g/kg). As drinkers with AUD frequently engage in very heavy drinking (8 to 10 drinks/occasion), doses of ≤0.8 g/kg may lack ecological validity. The present study examined the feasibility, tolerability, and safety of administering a very high alcohol dose (1.2 g/kg) to non-treatment-seeking AUD participants. METHODS: Sixty-one young adult AUD drinkers enrolled in the Chicago Social Drinking Project and completed 3 laboratory sessions at which they consumed a beverage with 1.2, 0.8, and 0.0 g/kg alcohol. Physiological responses (vital signs, nausea and vomiting, breath alcohol concentrations [BrAC]) were monitored throughout the sessions. After each session, participants completed a next-day survey of substance use, engagement in risky behaviors, and related consequences. RESULTS: Overall, the sample demonstrated good compliance with study procedures; 93% of participants adhered to presession alcohol abstinence requirements (indicated by BrAC < 0.003 g/dl), with no participants exhibiting serious alcohol withdrawal symptoms at arrival to study visits. The 1.2 g/kg alcohol dose achieved an expected mean peak BrAC of 0.13 g/dl at 60 minutes after drinking, which was well tolerated; the majority of the sample did not experience nausea (70%) or vomiting (93%), and dose effects on vital signs were not clinically significant. Finally, we demonstrated that the 1.2 g/kg alcohol dose is safe and not associated with postsession consequences, including reduced sleep time, atypical substance use, accidents or injuries, and severe hangovers. CONCLUSION: Results support the feasibility, tolerability, and safety of administering a very high alcohol dose to young adult drinkers with AUD within the context of a well-validated laboratory alcohol challenge paradigm. Utilizing an alcohol dose more consistent with naturalistic drinking patterns may foster greater ecological validity of laboratory paradigms for persons with moderate to severe AUD.

Intravenous Alcohol Administration Selectively Decreases Rate of Change in Elasticity of Demand in Individuals With Alcohol Use Disorder.

BACKGROUND: Alcohol demand is a key behavioral economic concept that provides an index of alcohol's relative reinforcing value. Initial studies have reported that alcohol demand increases during alcohol administration and in response to alcohol cues. However, the extent to which these effects are observed explicitly in samples composed of individuals with alcohol use disorder (AUD) and are operative in conjunction with each other has not been studied. METHODS: To address this gap in the literature, we assessed alcohol demand during an alcohol challenge and subsequent alcohol cue-exposure paradigm in non-treatment-seeking, alcohol-dependent (i.e., DSM-IV criteria) participants (N = 27). Specifically, participants completed 2 counterbalanced intravenous, placebo-controlled, alcohol administration sessions followed by a controlled cue-exposure paradigm. At baseline and at breath alcohol concentration of 0.06 g/dl, participants completed the alcohol purchase task, assessing estimated alcohol consumption at escalating prices. Participants were also assessed for alcohol demand following each cue exposure. RESULTS: During alcohol administration, there was a significant decrease in the rate of change in elasticity compared with placebo, and during the cue-reactivity paradigm, there was a significant main effect such that alcohol cues decreased the rate of change in elasticity relative to water cues. There were no statistically significant differences in other demand indices. CONCLUSIONS: These findings provide further evidence that alcohol administration increases price insensitivity and extends the literature on alcohol's effects on demand by using a clinical sample with AUD and by adding a placebo-alcohol condition.

Vaped, Not Stirred: Vaporized Alcohol Knowledge, Use, and Susceptibility.

Background: Vaporized alcohol is an alternative method of ingesting alcohol that has received significant attention in the press. However, research on vaporized alcohol to date is limited. Objectives: The current study sought to assess vaporized alcohol knowledge, use, and future susceptibility in diverse sample of young adults in the Southwest United States. Method: A cross-sectional survey design was used to assess perception and use of vaporized alcohol in a sample of 986 young adults in college gathered in 2015 and 2016. Results: Overall, 26% of participants had heard of vaporized alcohol, 1.7% had used vaporized alcohol, and 33.5% were susceptible to future vaporized alcohol use. Contrary to our hypothesis, heavy drinkers were not more likely to have tried vaporized alcohol. Further, there were no significant differences in vaporized alcohol use across any sociodemographic groups. Conclusions/Importance: Ever use of vaporized alcohol was low, which was generally consistent with prior research, debunking media reports that vaporized alcohol is a widespread problem. However, ongoing monitoring of this method of alcohol ingestions appears warranted, especially with different populations (i.e., adolescents, and young adults not in college) where no empirical research has been published to date.

Explicit Attitudes, Working Memory Capacity, and Driving After Drinking.

BACKGROUND: Attitudes toward driving after drinking are strongly predictive of drinking and driving behavior. This study tested working memory capacity (WMC) as a moderator of the association between attitudes and drinking and driving behavior. Consistent with dual process models of cognition, we hypothesized that the association between perceived danger and drinking and driving would be stronger for individuals with higher WMC. METHODS: Participants (N = 161) enrolled in larger alcohol administration study were randomly assigned to an alcohol (n = 57), placebol (n = 52), or control (n = 52, not included) beverage condition. Past-year frequency of driving after drinking and WMC were assessed at baseline. Attitudes were assessed by asking participants to rate the perceived danger of driving at their current level of intoxication twice on the ascending limb (AL1, AL2), at peak breath alcohol concentration (BrAC), and twice on the descending limb (DL1, DL2). RESULTS: Analyses across the BrAC curve indicated that the hypothesized interaction was observed for the alcohol but not placebo condition. Analyses for each assessment point indicated that the interaction was significant for the ascending limb and peak BrAC. In the alcohol condition, for those higher in WMC, lower perceived dangerousness was strongly associated with increased driving after drinking (AL1: incident rate ratios [IRR] = 5.87, Wald's χ2  = 12.39, p = 0.006, 95% CI [2.19, 15.75]; AL2: IRR = 8.17, Wald's χ2  = 11.39, p = 0.001, 95% CI [2.41, 27.66]; Peak: IRR = 5.11, Wald's χ2  = 9.84, p = 0.002, 95% CI [1.84, 14.16]). Associations were not significant at low WMC. CONCLUSIONS: Results suggest that individuals higher in WMC are more likely to act consistently with their explicit attitudes toward drinking and driving. Findings may have implications for existing drinking and driving interventions and suggest the potential for novel interventions targeting implicit associations or WMC.

The effects of alcohol intoxication and sexual interest on men's sexual persistence and hostility in a dating simulation.

Perpetrators of sexual assault are often intoxicated; however, few experimental studies evaluate alcohol's "in the moment" effects on sexual aggression. This study extends past theory and research by examining the acute effects of alcohol on men's decisions about how to respond to sexual refusals in a dating simulation. Men (N = 62) ages 21-29 were randomly assigned to consume alcohol (target breath alcohol level 0.080%) or no alcohol. Participants were encouraged to talk to a simulated woman and act as they would on an actual date. They made choices from a list which included nonsexual and sexual options. The female agent was programmed to engage in some sexual activities but refuse others. Refusals became more intense if participants persisted. Negative binomial regression analysis was used to test a path analytic model. As predicted, participants' self-reported desire to have sex was positively associated with choosing more consensual sexual activities during the simulation (i.e., activities in which the woman willingly engaged). Consensual sexual activities were positively associated with the number of times participants persisted after the woman refused. Alcohol moderated this relationship such that it was stronger for intoxicated men than sober men. The more sexual refusals participants received, the more hostile verbal comments they made to the woman. Contrary to our predictions, this relationship was not moderated by alcohol condition. Because participants had multiple opportunities to escalate their aggression or desist, this paradigm provides new insights into the mechanisms through which intoxication enhances the likelihood of sexual aggression in dating situations.

Sample Entropy of the Heart Rate Reflects Properties of the System Organization of Behaviour.

Cardiac activity is involved in the processes of organization of goal-directed behaviour. Each behavioural act is aimed at achieving an adaptive outcome and it is subserved by the actualization of functional systems consisting of elements distributed across the brain and the rest of the body. This paper proposes a system-evolutionary view on the activity of the heart and its variability. We have compared the irregularity of the heart rate, as measured by sample entropy (SampEn), in behaviours that are subserved by functional systems formed at different stages of individual development, which implement organism-environment interactions with different degrees of differentiation. The results have shown that SampEn of the heart rate was higher during performing tasks that included later acquired knowledge (foreign language vs. native language; mathematical vocabulary vs. general vocabulary) and decreased in the stress and alcohol conditions, as well as at the beginning of learning. These results are in line with the hypothesis that irregularity of the heart rate reflects the properties of a set of functional systems subserving current behaviour, with higher irregularity corresponding to later acquired and more complex behaviour.

Association between overall rate of change in rising breath alcohol concentration and the magnitude of acute tolerance of subjective intoxication via the Mellanby method.

OBJECTIVE: The magnitude of acute tolerance is a strong predictor of the development of longer-term chronic tolerance and plays a decisive role in risky decisions (e.g., driving after drinking). Therefore, it is important to identify factors that increase the magnitude of this adaptive process. This study explored whether acute tolerance magnitude varied as a function of the overall rate of increase in breath alcohol concentration (BrAC). METHODS: Twenty-nine young adult social drinkers (M age = 22.55, SD = 3.10; 62.1% women) consumed a moderate dose of alcohol (men: 0.86 g/kg, women: 0.75 g/kg) in a controlled laboratory setting. Subjective intoxication was assessed at matched BrACs (~0.060 g/dl) on each limb of the BrAC curve. RESULTS: Hierarchical regression results indicated that faster overall increases in BrAC on the ascending limb were associated with greater acute tolerance for subjective intoxication ratings (p < .01, R2  = .29). CONCLUSIONS: These results present some of the first evidence that faster increases in BrAC may be associated with greater acute tolerance, as indicated by greater reduction in subjective intoxication across the limbs of the BrAC curve. This greater reduction may, in turn, promote heavier drinking and/or engagement in behaviors for which one is unfit (e.g., driving after drinking).

A prospective study of genetic factors, human laboratory phenotypes, and heavy drinking in late adolescence.

Subjective responses to alcohol are considered candidate endophenotypes for alcohol use disorder and appear to anticipate future consumption. However, prospective studies have been rare, and laboratory research has typically examined subjective responses absent measures of self-administration. This study examined the association of subjective responses with subsequent laboratory self-administration, also evaluating laboratory phenotypes in relation to putative genetic risk factors [family history (FH) of alcohol dependence and OPRM1 genotype] and subsequent heavy drinking. Participants (N = 61, M = 19.89 years, SD = 0.86) completed laboratory sessions involving intravenous alcohol challenge (Session 1) and free-access intravenous self-administration (Session 2), followed by prospective assessments. Multilevel modeling showed that higher reported stimulation and lower sedation during Session 1 independently predicted greater alcohol self-administration during Session 2. Although self-administration did not differ by FH group, participants with the OPRM1 118G allele evidenced steeper breath alcohol concentration (BrAC) trajectories and greater peak BrAC relative to 118A homozygous participants. Prospective analyses supported significant indirect associations between Session 1 subjective responses and 6-month heavy drinking via peak BrAC in Session 2. Additionally, significant indirect associations of FH (via Session 1 stimulation and Session 2 peak BrAC) and OPRM1 (via peak BrAC) with follow-up heavy drinking were observed. These results further support the utility of human laboratory phenotypes in prospective studies of alcohol use disorder risk and highlight the potential role of self-administration phenotypes in longitudinal research.

Alcohol Vapor Inhalation as a Model of Alcohol-Induced Organ Disease.

BACKGROUND: Chronic intermittent ethanol vapor (CIEV) exposure has been used extensively to produce rodent models of alcohol dependence, but unlike other models of alcohol abuse, CIEV has not been assessed as a model of end-organ damage. The purpose of this study was to characterize the effects of CIEV on peripheral organ systems affected by alcohol abuse, including the liver, lungs, and cardiovascular system. METHODS: Adult male Sprague-Dawley rats were exposed to daily CIEV for a period of 8 weeks (14HR ON/10HR OFF), producing blood alcohol levels of ~200 mg/dl. Controls were exposed to room air. After 8 weeks, echocardiography was performed to assess cardiac function. Indices of liver injury (alanine and aspartate aminotransferases [ALT and AST]; cytochrome p450 2E1 [CYP2E1]; alcohol dehydrogenase [ADH]; Oil Red O and triglyceride content; lipid peroxidation; inflammatory cytokine expression; and macrophage infiltration), and lung inflammatory cell count, proinflammatory cytokine expression, and lipid peroxidation were measured. RESULTS: Left ventricular posterior wall thickness was significantly decreased, and systolic blood pressure was significantly elevated by CIEV compared with air controls. CIEV led to a significant increase in plasma ALT and triglycerides compared with room air controls. CIEV did not affect liver triglyceride content, lipid staining or peroxidation, but increased CYP2E1 and chemokine (C-C motif) ligand 2 (CCL2) protein expression, while decreasing ADH expression. CIEV significantly increased numbers of both polymorphonuclear neutrophils and lymphocytes in the bronchoalveolar lavage fluid, indicative of pulmonary inflammation. However, CIEV did not produce significant changes in lung mass, pulmonary lipid peroxidation, inflammatory cytokine expression, or edema. CONCLUSIONS: These results show that CIEV produces hepatic, pulmonary, and cardiovascular effects in rats similar to those found in other models of chronic alcohol administration. Alcohol vapor administration is a novel method of alcohol-induced tissue injury with high potential for widespread use in alcohol toxicology research.

Acute Effects of Intoxication and Arousal on Approach/Avoidance Biases Toward Sexual Risk Stimuli in Heterosexual Men.

This study tested the effects of alcohol intoxication and physiological arousal on cognitive biases toward erotic stimuli and condoms. Ninety-seven heterosexual men were randomized to 1 of 6 independent conditions in a 2 (high arousal or control) × 3 (alcohol target BAC = 0.08, placebo, or juice control) design and then completed a variant of the Approach-Avoidance Task (AAT). The AAT assessed reaction times toward approaching and avoiding erotic stimuli and condoms with a joystick. Consistent with hypotheses, the alcohol condition exhibited an approach bias toward erotic stimuli, whereas the control and placebo groups exhibited an approach bias toward condom stimuli. Similarly, the participants in the high arousal condition exhibited an approach bias toward erotic stimuli and the low arousal control condition exhibited an approach bias toward condoms. The results suggest that acute changes in intoxication and physiological arousal independently foster biased responding toward sexual stimuli and these biases are associated with sexual risk intentions.

Perceived danger while intoxicated uniquely contributes to driving after drinking.

BACKGROUND: Previous findings suggest that alcohol alters perceptions of risky behaviors such as drinking and driving. However, studies testing these perceptions as a predictor of drinking and driving typically measure these perceptions while participants are sober. This study tested whether the perceived danger of driving after drinking assessed while intoxicated was associated with increased willingness to drive and self-reported drinking-and-driving behavior over and above perceptions assessed while sober. Additionally, we tested the effect of acute tolerance on the perceived danger of driving after drinking assessed on the ascending and descending limbs of the breath alcohol concentration (BrAC) curve. METHODS: Eighty-two young adults attended 2 counterbalanced laboratory sessions. In one session, participants consumed a moderate dose of alcohol (men: 0.72 g/kg, women: 0.65 g/kg) and reported their perceived danger of driving and willingness to drive at multiple points across the BrAC curve. On a separate occasion, participants remained sober and appraised the dangerousness of driving at a hypothetical, illegal BrAC. RESULTS: Perceptions of the dangerousness of driving following alcohol administration were associated with increased willingness to drive and higher rates of self-reported drinking-and-driving behavior over and above perceptions reported when sober. Furthermore, perceived danger was reduced on the descending limb of the BrAC curve, compared with the ascending limb, suggesting the occurrence of acute tolerance. CONCLUSIONS: Results from this study suggest that intoxicated perceptions are uniquely associated with drinking-and-driving decisions and that the perceived danger of drinking and driving is lower on the descending limb of the BrAC curve. Efforts to prevent alcohol-impaired driving have focused on increasing awareness of the danger of driving after drinking. Prevention efforts may be enhanced by educating drivers about how intoxication can alter perceived danger, and interventions may benefit from targeting perceptions of dangerousness while individuals are intoxicated in addition to when they are sober.

Limited evidence that alcohol affects emotional face processing via interoceptive pathways, a registered report.

BACKGROUND: Our brain uses interoceptive signals from the body to shape how we perceive emotions in others; however, whether interoceptive signals can be manipulated to alter emotional perceptions is unknown. This registered report examined whether alcohol administration triggers physiological changes that alter interoceptive signals and manipulate emotional face processing. METHODS: Participants (n=36) were administered an alcohol or placebo beverage. Cardiovascular physiology (Heartrate variability, HRD) was recorded before and after administration. Participants completed a behavioral task in which emotional faces were presented in synchrony with different phases of the cardiac cycle (i.e., systole/diastole) to index of how interoceptive signals amplify them. HYPOTHESES: We hypothesized that alcohol administration would disrupt the cardiac amplification of emotional face processing. We further explored whether this disruption depended on the nature and magnitude of changes in cardiovascular physiology after alcohol administration. RESULTS: We observed no main effects or interactions between alcohol administration and emotional face processing. We found that HRV at baseline negatively correlated with the cardiac amplification of emotional faces. The extent to which alcohol impacted HRV negatively correlated with the cardiac amplification of angry faces. CONCLUSIONS: This registered report failed to validate the primary hypotheses but offers some evidence that the effects of alcohol on emotional face processing, if any, could be mediated via changes in basic physiological signals that are integrated via interoceptive mechanisms. Results are interpreted within the context of interoceptive inference and could feed novel perspectives for the interplay between physiological sensitivity and interoception in the development of drug-related behaviors.

Are medication effects on subjective response to alcohol and cue-induced craving associated? A meta regression study.

RATIONALE: Alcohol administration and cue-reactivity paradigms are frequently used to screen for the initial efficacy of medications for alcohol use disorder (AUD). While medication effects on the primary outcomes for these paradigms are assumed to be qualitatively related, there is a critical lack of quantitative evidence to support this hypothesis. OBJECTIVES: The study aims to test the relationship between medication effect sizes on subjective response to alcohol administration and medication effect sizes for cue-induced craving to cue exposure, using meta-analysis. METHODS: Systematic literature searches were conducted to identify randomized trials, wherein AUD medications were tested using the alcohol administration and/or cue-reactivity paradigms. From these studies, descriptive statistics were collected to compute medication effect sizes on the primary outcomes for each respective paradigm. With medication as the unit of analysis, medication effect sizes in alcohol administration studies were compared with medication effect sizes in cue-reactivity studies using the Williamson-York regression which allows for meta-regression across independent samples. RESULTS: Medication effect sizes on alcohol-induced stimulation and alcohol-induced craving were not significantly associated with medication effect sizes on cue-induced alcohol craving (k stimulation = 10 medications, [Formula: see text] and k craving = 11 medications, [Formula: see text] (SE = 0.237), [Formula: see text]), respectively. Medication effect sizes on alcohol-induced sedation were significantly associated with medication effects on cue-induced craving (k = 10 medications, [Formula: see text] (SE = 0.258), [Formula: see text]), such that medications that increased alcohol-induced sedation were more likely to reduce cue-induced alcohol craving. CONCLUSIONS: With the exception of alcohol-induced sedation, there is little quantitative evidence of medication effects on subjective response domains measured during alcohol administration parallel medication effects on cue-induced alcohol craving. To provide additional context to the current study, future work should examine whether cue-reactivity findings predict clinical trial outcomes.