Decision making and binge drinking: a longitudinal study

Understanding sex differences and the translational value of models of persistent substance use despite negative consequences

Persistent substance use despite negative consequences is a key facet of substance use disorder. The last decade has seen the preclinical field adopt the use of punishment to model adverse consequences associated with substance use. This has largely involved the pairing of drug use with either electric foot shock or quinine, a bitter tastant. Whilst at face value, these punishers may model aspects of the physical and psychological consequences of substance use, such models are yet to assist the development of approved medications for treatment. This review discusses progress made with animal models of punishment to understand the behavioral consequences of persistent substance use despite negative consequences. We highlight the importance of examining sex differences, especially when the behavioral response to punishment changes following drug exposure. Finally, we critique the translational value these models provide for the substance use disorder field.

Adolescent brain maturation and the neuropathological effects of binge drinking: A critical review

Adolescence is a transitional stage marked by continued brain development. This period is accompanied by physical and neurochemical modifications in the shape and function of the hippocampus, prefrontal cortex, and other limbic system structures. Brain maturation during adolescence, which is typically governed by intrinsic factors, can be dramatically altered by environmental influences such as drugs and alcohol. Unlike many other addictive substances, binge drinking is very common and normative among teenagers and young adults. This repeated pattern of excessive alcohol consumption in adolescents has been shown to cause behavioral changes and neurocognitive impairments that include increased anxiety, risky decision-making, and learning deficits, which could lead to the development of alcohol use disorder (AUD). This manuscript highlights factors that lead to adolescent binge drinking, discusses maturational changes that occur in an adolescent's brain, and then evaluates the effect of adolescent alcohol consumption on brain structure, function, and neurocognitive abilities in both human studies and animal models. The impact of gender/sex and COVID-19 are briefly discussed. Understanding the factors that promote the onset of adolescent binge drinking and its undesirable consequences could serve as a catalyst for developing therapeutic agents that would decrease or eradicate the damaging effects of alcohol on an adolescent brain.

Sex-specific decision-making impairments and striatal dopaminergic changes after binge drinking history in rats

Binge drinking (BD) is a harmful behavior for health and is a predictive factor for the development of alcohol addiction. Weak decision-making (DM) capacities could play a role in the vulnerability to BD which in turn would lead to DM impairments, thus perpetuating BD. Longitudinal preclinical studies are however lacking and necessary to understand this complex relationship. Both DM and BD are influenced by sex and involve dopamine release in the core of the nucleus accumbens, a central mechanism regulated by dopamine D2/3 autoreceptors. In this context, we used an operant self-administration procedure of BD in male and female rats, and longitudinally assessed DM capacity, memory and anxiety-like behavior. To better understand the mechanisms potentially involved in the relationship between DM and BD, ex vivo dopamine transmission was assessed short term after the end of the binge exposure in the core of the nucleus accumbens (NAc) using the fast-scan cyclic voltammetry (FSCV) technique and the D2/3 agonist quinpirole. We found important basal sex differences in DM, with female rats showing better performances at baseline. Choice processes were impaired exclusively in males after BD history, associated with a decrease in impulse control in both sexes, while memory and anxiety-like behavior were not affected. Our neurobiological results demonstrate that BD did not affect basal dopamine signaling in the NAc core, regardless of the sex, but reveal changes in the sensitivity to the inhibitory effects of quinpirole in females. DM impairments were neither associated with changes in basal dopamine signaling nor pre-synaptic D2 activity. Overall, our findings show that BD affects both DM processes and dopamine transmission in the core of the NAc in a sex-related manner, further suggesting that these effects may play a role in the vicious cycle leading to BD perpetuation and the early onset of AUD. Our results may inform novel strategies for therapeutic and prevention interventions.

Sexually dimorphic development of the mesolimbic dopamine system is associated with nuanced sensitivity to adolescent alcohol use

Alcohol use remains a major public health concern and is especially prevalent during adolescence. Adolescent alcohol use has been linked to several behavioral abnormalities in later life, including increased risk taking and impulsivity. Accordingly, when modeled in animals, male rats that had moderate alcohol consumption during adolescence exhibit multiple effects in adulthood, including increased risk taking, altered incentive learning, and greater release of dopamine in the mesolimbic pathway. It has been proposed that alcohol arrests neural development, "locking in" adolescent physiological, and consequent behavioral, phenotypes. Here we examined the feasibility that the elevated dopamine levels following adolescent alcohol exposure are a "locked in" phenotype by testing mesolimbic dopamine release across adolescent development. We found that in male rats, dopamine release peaks in late adolescence, returning to lower levels in adulthood, consistent with the notion that high dopamine levels in adolescence-alcohol-exposed adults were due to arrested development. Surprisingly, dopamine release in females was stable across the tested developmental window. This result raised a quandary that arrested dopamine levels would not differ from normal development in females and, therefore, may not contribute to pathological behavior. However, the aforementioned findings related to risk-based decision-making have only been performed in male subjects. When we tested females that had undergone adolescent alcohol use, we found that neither risk attitude during probabilistic decision-making nor mesolimbic dopamine release was altered. These findings suggest that different developmental profiles of the mesolimbic dopamine system across sexes result in dimorphic susceptibility to alcohol-induced cognitive and motivational anomalies exposure.

Chemogenetic inhibition of corticotropin-releasing factor neurons in the central amygdala alters binge-like ethanol consumption in male mice

Repetitive bouts of binge drinking can lead to neuroplastic events that alter ethanol's pharmacologic effects and perpetuate excessive consumption. The corticotropin-releasing factor (CRF) system is an example of ethanol-induced neuroadaptations that drive excessive ethanol consumption. Our laboratory has previously shown that CRF antagonist, when infused into the central amygdala (CeA), reduces binge-like ethanol consumption. The present study extends this research by assessing the effects of silencing CRF-producing neurons in CeA on binge-like ethanol drinking stemming from "Drinking in the Dark" (DID) procedures. CRF-ires-Cre mice underwent surgery to infuse Gi/o-coupled Designer Receptors Exclusively Activated by Designer Drugs (DREADD) virus or a control virus into either the CeA or basolateral amygdala (BLA). Gi/o-DREADD-induced CRF-neuronal inhibition in the CeA resulted in a 33% decrease in binge-like ethanol consumption. However, no effect on ethanol consumption was seen after DREADD manipulation in the BLA. Moreover, CeA CRF-neuronal inhibition had no effect on sucrose consumption. The effects of silencing CRF neurons in the CeA on ethanol consumption are not secondary to changes in motor function or anxiety-like behaviors as assessed in the open-field test (OFT). Finally, the DREADD construct's functional ability to inhibit CRF-neuronal activity was demonstrated by reduced ethanol-induced c-Fos following DREADD activation. Together, these data suggest that the CRF neurons in the CeA play an important role in binge ethanol consumption and that inhibition of the CRF-signaling pathway remains a viable target for manipulating binge-like ethanol consumption. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Effects of binge drinking during adolescence and emerging adulthood on the brain: A systematic review of neuroimaging studies

Binge drinking (BD) is a common pattern of alcohol consumption which is generating great concern because of its deleterious consequences. We selected 33 neuroimaging studies of healthy young binge drinkers (BDs) by following PRISMA guidelines. This review provides a comprehensive overview of the relationship between BD and neurocognitive anomalies reported across magnetic resonance studies. Moreover, this work is the first in which results of relatively new imaging techniques, such as resting-state functional connectivity (RS-FC) and neurite orientation dispersion and density imaging (NODDI), have been reviewed using a systematic procedure. We established strict inclusion criteria in order to isolate the various potential effects of BD on the adolescent brain. Two authors independently evaluated the methodological quality, assessing different aspects related to sample size, and statistical correction methods, which are of particular importance in neuroimaging studies. BD is associated with structural and functional anomalies in several cortical and subcortical brain regions intimately involved in the control and regulation of impulsive or risky behaviours, as well as in the processing of reinforcing stimuli.

Alcohol dependence decreases functional activation of the caudate nucleus during model-based decision processes

BACKGROUND

Impaired decision making, a key characteristic of alcohol dependence (AD), manifests in continuous alcohol consumption despite severe negative consequences. The neural basis of this impairment in individuals with AD and differences with known neural decision mechanisms among healthy subjects are not fully understood. In particular, it is unclear whether the choice behavior among individuals with AD is based on a general impairment of decision mechanisms or is mainly explained by altered value attribution, with an overly high subjective value attributed to alcohol-related stimuli.

METHODS

Here, we use a functional magnetic resonance imaging (fMRI) monetary reward task to compare the neural processes of model-based decision making and value computation between AD individuals (n = 32) and healthy controls (n = 32). During fMRI, participants evaluated monetary offers with respect to dynamically changing constraints and different levels of uncertainty.

RESULTS

Individuals with AD showed lower activation associated with model-based decision processes in the caudate nucleus than controls, but there were no group differences in value-related neural activity or task performance.

CONCLUSIONS

Our findings highlight the role of the caudate nucleus in impaired model-based decisions of alcohol-dependent individuals.

Individual strategies in the rat gambling task are related to voluntary alcohol intake, but not sexual behavior, and can be modulated by naltrexone

INTRODUCTION

Gambling disorder (GD) is the first non-substance or behavioral addiction to be included in substance-related and addictive disorders in DSM-5. Since GD is a younger phenomenon relative to alcohol and substance use disorders, little is known about potential unique features in GD and to what extent characteristics are shared with alcohol and substance use disorders. The rat gambling task (rGT) is used to study decision-making in rats. This study aimed to identify individual differences in rGT strategies and explore the stability of these strategies over time. Moreover, motor impulsivity, sexual behavior, and voluntary alcohol intake were examined in rats with different rGT strategies. Finally, the response to naltrexone on performance in rats with different rGT strategies was investigated.

METHODS

Male Lister hooded rats (n = 40) underwent repeated testing in the rGT, repeated copulatory behavioral tests, and 7 weeks of voluntary alcohol intake through a modified intermittent two-bottle free-choice paradigm. Finally, rats were treated with naltrexone prior to testing in the rGT.

RESULTS

The results revealed individual choice strategies in the rGT that were stable over time, even after multiple interruptions and other behavioral testing. The rats with a risky choice strategy displayed higher motor impulsivity and voluntary alcohol intake than the other groups. No difference in sexual behavior was found between the different rGT groups. Finally, in all rats irrespectively of rGT strategy, treatment with naltrexone decreased the number of completed trials and premature responses, and increased omissions, which indicates an overall lowered motivation.

DISCUSSION

In conclusion, rats with risky rGT strategies had higher voluntary alcohol intake but not elevated sexual behavior, indicating shared underlying mechanisms between rGT strategies and alcohol intake but not natural rewards in terms of sexual behavior. Finally, naltrexone treatment resulted in an overall lowered motivation in the rGT.

Adolescent Binge Drinking Is Associated With Accelerated Decline of Gray Matter Volume

The age- and time-dependent effects of binge drinking on adolescent brain development have not been well characterized even though binge drinking is a health crisis among adolescents. The impact of binge drinking on gray matter volume (GMV) development was examined using 5 waves of longitudinal data from the National Consortium on Alcohol and NeuroDevelopment in Adolescence study. Binge drinkers (n = 166) were compared with non-binge drinkers (n = 82 after matching on potential confounders). Number of binge drinking episodes in the past year was linked to decreased GMVs in bilateral Desikan-Killiany cortical parcellations (26 of 34 with P < 0.05/34) with the strongest effects observed in frontal regions. Interactions of binge drinking episodes and baseline age demonstrated stronger effects in younger participants. Statistical models sensitive to number of binge episodes and their temporal proximity to brain volumes provided the best fits. Consistent with prior research, results of this study highlight the negative effects of binge drinking on the developing brain. Our results present novel findings that cortical GMV decreases were greater in closer proximity to binge drinking episodes in a dose-response manner. This relation suggests a causal effect and raises the possibility that normal growth trajectories may be reinstated with alcohol abstinence.

Component Processes of Decision Making in a Community Sample of Precariously Housed Persons: Associations With Learning and Memory, and Health-Risk Behaviors

The Iowa Gambling Task (IGT) is a widely used measure of decision making, but its value in signifying behaviors associated with adverse, "real-world" consequences has not been consistently demonstrated in persons who are precariously housed or homeless. Studies evaluating the ecological validity of the IGT have primarily relied on traditional IGT scores. However, computational modeling derives underlying component processes of the IGT, which capture specific facets of decision making that may be more closely related to engagement in behaviors associated with negative consequences. This study employed the Prospect Valence Learning (PVL) model to decompose IGT performance into component processes in 294 precariously housed community residents with substance use disorders. Results revealed a predominant focus on gains and a lack of sensitivity to losses in these vulnerable community residents. Hypothesized associations were not detected between component processes and self-reported health-risk behaviors. These findings provide insight into the processes underlying decision making in a vulnerable substance-using population and highlight the challenge of linking specific decision making processes to "real-world" behaviors.

What We Talk About When We Talk About Binge Drinking: Towards an Integrated Conceptualization and Evaluation

RATIONALE

Binge drinking (BD), characterized by recurring alternations between intense intoxication episodes and abstinence periods, is the most frequent alcohol consumption pattern in youth and is growing in prevalence among older adults. Many studies have underlined the specific harmful impact of this habit by showing impaired abilities in a wide range of cognitive functions among binge drinkers, as well as modifications of brain structure and function.

AIMS

Several controversies and inconsistencies currently hamper the harmonious development of the field and the recognition of BD as a specific alcohol consumption pattern. The main concern is the absence of consensual BD conceptualization, leading to variability in experimental group selection and alcohol consumption evaluation. The present paper aims at overcoming this key issue through a two-step approach.

METHODS AND CONCLUSIONS

First, a literature review allows proposing an integrated BD conceptualization, distinguishing it from other subclinical alcohol consumption patterns. Six specific characteristics of BD are identified, namely, (1) the presence of physiological symptoms related to BD episodes, (2) the presence of psychological symptoms related to BD episodes, (3) the ratio of BD episodes compared to all alcohol drinking occasions, (4) the frequency of BD episodes, (5) the consumption speed and (6) the alternation between BD episodes and soberness periods. Second, capitalizing on this conceptual clarification, we propose an evaluation protocol jointly measuring these six BD characteristics. Finally, several research perspectives are presented to refine the proposed conceptualization.

Pharmacological evidence of a cholinergic contribution to elevated impulsivity and risky decision-making caused by adding win-paired cues to a rat gambling task

BACKGROUND

Pairing rewards with sensory stimulation, in the form of auditory and visual cues, increases risky decision-making in both rats and humans. Understanding the neurobiological basis of this effect could help explain why electronic gambling machines are so addictive, and inform treatment development for compulsive gambling and gaming. Numerous studies implicate the dopamine system in mediating the motivational influence of reward-paired cues; recent data suggest the cholinergic system also plays a critical role. Previous work also indicates that cholinergic drugs alter decision-making under uncertainty.

AIMS

We investigated whether the addition of reward-concurrent cues to the rat gambling task (crGT) altered the effects of peripherally administered cholinergic compounds.

METHODS

Muscarinic and nicotinic agonists and antagonists were administered to 16 male, Long-Evans rats trained on the crGT. Measures of optimal/risky decision-making and motor impulsivity were the main dependent variables of interest.

RESULTS

The muscarinic receptor antagonist scopolamine improved decision-making overall, decreasing selection of one of the risky options while increasing choice of the more advantageous options. The muscarinic agonist oxotremorine increased choice latency but did not significantly affect option preference. Neither the nicotinic antagonist mecamylamine nor the agonist nicotine affected choice patterns, but mecamylamine decreased premature responding, an index of motor impulsivity.

CONCLUSIONS

These results contrast sharply from those obtained previously using the uncued rGT, and suggest that the deleterious effects of win-paired cues on decision-making and impulse control may result from elevated cholinergic tone.

Acute rewarding and disinhibiting effects of alcohol as indicators of drinking habits

RATIONALE

Laboratory studies have reliably shown that heightened sensitivity to the rewarding effects of alcohol is associated with heavier drinking patterns. More recently, there has been research to suggest that heightened sensitivity to the disinhibiting effects of alcohol might also contribute to drinking habits. Most research on the acute effects of alcohol has focused on drinking magnitudes averaged across participants with little attention paid to how individual differences influence alcohol abuse potential. In large part, this is due to limited sample sizes in previous laboratory studies.

OBJECTIVES

This study overcomes previous limitations by testing the degree to which individual differences in acute sensitivity and tolerance to the rewarding and disinhibiting effects of alcohol relate to drinking behavior in a large sample size.

METHODS

Data from six laboratory studies were aggregated to comprise a sample of 181 adults. Participants' level of "liking" (the effects of alcohol) and disinhibition were assessed following 0.65 g/kg alcohol once during the ascending limb of the blood alcohol concentration (BAC) curve and again at the same BAC during the descending limb of the curve. The measures were also assessed following placebo.

RESULTS

Alcohol increased ratings of liking and behavioral disinhibition. Heavier drinking was associated with heightened sensitivity to liking on the ascending limb. Additionally, those who showed reduced acute tolerance to both disinhibition and liking were also heavier drinkers.

CONCLUSIONS

These data suggest that individual variability in liking the effects of alcohol and persistent disinhibition are key indicators of drinking habits.

Frequency of Recent Binge Drinking Is Associated With Sex-Specific Cognitive Deficits: Evidence for Condition-Dependent Trait Expression in Humans

Evolutionary theory suggests that commonly found sex differences are largest in healthy populations and smaller in populations that have been exposed to stressors. We tested this idea in the context of men’s typical advantage (vs. women) in visuospatial abilities (e.g., mental rotation) and women’s typical advantage (vs. men) in social-cognitive (e.g., facial-expression decoding) abilities, as related to frequent binge drinking. Four hundred nineteen undergraduates classified as frequent or infrequent binge drinkers were assessed in these domains. Trial-level multilevel models were used to test a priori Sex × Group (binge drinking) interactions for visuospatial and social-cognitive tasks. Among infrequent binge drinkers, men’s typical advantage in visuospatial abilities and women’s typical advantage in social-cognitive abilities was confirmed. Among frequent binge drinkers, men’s advantage was reduced for one visuospatial task (Δ d = 0.29) and eliminated for another (Δ d = 0.75), and women’s advantage on the social-cognitive task was eliminated (Δ d = 0.12). Males who frequently engaged in extreme binges had exaggerated deficits on one of the visuospatial tasks, as did their female counterparts on the social-cognitive task. The results suggest sex-specific vulnerabilities associated with recent, frequent binge drinking, and support an evolutionary approach to the study of these vulnerabilities.

Latent Profile Analysis of Heavy Episodic Drinking in Emerging Adults: A Reinforcer Pathology Approach

BACKGROUND

Heavy episodic drinking (HED) is a major public health problem among emerging adults (individuals 18 to 25), but with considerable heterogeneity in concurrent substance use and psychopathology. The current study used latent profile analysis (LPA) to detect discrete subgroups of HED based on alcohol, other drug severity, and concurrent psychopathology. A reinforcer pathology approach was used to understand motivational differences among the latent subgroups.

METHODS

Participants were 2 samples of emerging adults reporting regular HED, 1 Canadian (n = 730) and 1 American (n = 602). Indicators for the LPA were validated dimensional self-report assessments of alcohol severity, cannabis severity, other drug severity, nicotine dependence, depression, anxiety, posttraumatic stress disorder, and attention-deficit/hyperactivity disorder. Reinforcer pathology indicators were measures of alcohol demand, proportionate substance-related reinforcement, and discounting of future rewards.

RESULTS

The LPA yielded parallel 3-class solutions in both samples. The largest subgroup was characterized by comparatively low substance severity and psychopathology (Low overall severity). The second largest subgroup was characterized by comparatively high alcohol and other drug severity (excluding tobacco) and high levels of psychopathology (Heavy alcohol & high psychiatric severity). The third subgroup exhibited high alcohol, smoking and intermediate levels of other substance use and psychopathology (Heavy alcohol, smoking, & intermediate psychiatric severity). The Heavy alcohol & high psychiatric severity and Heavy alcohol, smoking, & intermediate psychiatric severity subgroups exhibited significantly higher alcohol demand, greater proportionate substance-related reinforcement, and steeper delay discounting.

CONCLUSIONS

Parallel latent subgroups of emerging adults engaging in HED were present in both samples, and the high-risk subgroups were significantly differentiated by the reinforcer pathology indicators. These latent profiles may ultimately inform heterogeneity in the longitudinal course of HED in emerging adults.

Motivational and Control Mechanisms Underlying Adolescent versus Adult Alcohol Use

Increased motivation towards alcohol use and suboptimal behavioral control are suggested to predispose adolescents to alcohol use disorders (AUDs). Paradoxically however, most adolescent AUDs resolve over time without any formal intervention, suggesting adolescent resilience to AUDs. Importantly, studies directly comparing adolescent and adult alcohol use are largely missing. We therefore aimed to unravel the moderating role of age in the relation between alcohol use and motivational and control-related cognitive processes in 45 adolescent drinkers compared to 45 adults. We found that enhancement drinking motives and impulsivity related positively to alcohol use. Although enhancement drinking motives and impulsivity were higher in adolescents, the strength of the relation between these measures and alcohol use did not differ between age groups. None of the alcohol use-related motivational measures (i.e., craving, attentional bias, and approach bias) and behavioral control measures (i.e., interference control, risky decision making, and working-memory) were associated with alcohol use or differed between age groups. These findings support the role of impulsivity and affective sensitivity in adolescent drinking but question the moderating role of age therein. The current study contributes towards understanding the role of age in the relation between alcohol use and cognition.

ELSA 2014 Cohort: Risk Factors Associated With Heavy Episodic Drinking Trajectories in Argentinean College Students

Heavy episodic drinking (HED) is highly prevalent in college students. In Argentina, there is a notable lack of longitudinal studies examining drinking trajectories. The present study identified HED trajectories in Argentinean college students during the first 3 years of college (seven waves) and examined the association between risk factors for alcohol use and HED trajectories. The sample was composed of 1,240 college students [63.1% women, aged 18–25 years (M = 19.1 ± 1.7)] who completed at least three waves (the first data collection and ≥2 follow-ups). For 3 years, participants completed seven surveys that measured HED frequency, age of drinking onset, drunkenness occurrence, trait impulsivity, family history of alcohol abuse, stressful life events, and perceived peer’s drinking. Latent Class Growth Analysis (LCGA) and Multinomial Logistic Regression (MLR) were used to identify the pattern and number of HED trajectories and to explore which risk factors better distinguished between the trajectories, respectively. Six HED trajectories were identified: Heavy Stable Frequency, Moderate Stable Frequency, Moderate Decreasing Frequency, Stable Infrequent, Decreasing Infrequent, and No-HED. Younger age of drinking onset, alcohol intoxication, greater perception of peer drinking frequency and higher levels of impulsivity (i.e., sensation seeking, lack of premeditation, and positive urgency) increased the probability of belonging to the trajectories with more frequent HED. These trajectories partially coincide with those identified in studies from other cultures. Unlike previous studies, we did not find a trajectory with increasing/ascending HED frequency. This may be related to contextual/cultural variables unique to Argentina, like differences in the age when the peak in alcohol consumption is reached or the legal minimum age to buy alcoholic beverages in this country, and the idiosyncratic elements that characterize college life in Argentina. This work represents a step forward in the identification of risk factors differentiating between different HED trajectories, and help understand changes in alcohol use during college, in an understudied population.

Effects of Ethanol Exposure During Adolescence or Adulthood on Locomotor Sensitization and Dopamine Levels in the Reward System

Behavioral sensitization is a process of neuroadaptation characterized by a gradual increase in motor behaviors. The major neural substrates involved in the behavioral sensitization lie on the dopaminergic mesocorticolimbic pathway, which is still under development during adolescence. To investigate age-differences in ethanol behavioral sensitization and dopamine levels in distinct brain regions of the reward system, adolescent and adult mice were repeatedly pretreated with saline or ethanol (2.0 g/kg i.p.) during 15 consecutive days and challenged with saline or ethanol 5 days after pretreatment. Dopamine and its metabolites were measured in tissue samples of the prefrontal cortex (PFC), nucleus accumbens (NAc) and striatum by HPLC analysis. While repeated ethanol administration resulted in the development of locomotor sensitization in both adult and adolescent mice, only the adults expressed sensitization to a subsequent ethanol challenge injection. Neurochemical results showed reduced dopamine levels in adolescents compared to adults. Specifically, mice pretreated with ethanol during adolescence displayed lower dopamine levels in the PFC compared to the respective adult group in response to an ethanol challenge injection, and preadolescent mice exhibited lower dopamine levels in the NAc following an acute ethanol treatment compared to adults. These findings suggest that adolescent mice are not only less sensitive to the expression of ethanol-induced sensitization than adults, but also show lower dopamine content after ethanol exposition in the PFC and NAc.

Detecting Binge Drinking and Alcohol-Related Risky Behaviours from Twitter's Users: An Exploratory Content- and Topology-Based Analysis

Binge Drinking (BD) is a common risky behaviour that people hardly report to healthcare professionals, although it is not uncommon to find, instead, personal communications related to alcohol-related behaviors on social media. By following a data-driven approach focusing on User-Generated Content, we aimed to detect potential binge drinkers through the investigation of their language and shared topics. First, we gathered Twitter threads quoting BD and alcohol-related behaviours, by considering unequivocal keywords, identified by experts, from previous evidence on BD. Subsequently, a random sample of the gathered tweets was manually labelled, and two supervised learning classifiers were trained on both linguistic and metadata features, to classify tweets of genuine unique users with respect to media, bot, and commercial accounts. Based on this classification, we observed that approximately 55% of the 1 million alcohol-related collected tweets was automatically identified as belonging to non-genuine users. A third classifier was then trained on a subset of manually labelled tweets among those previously identified as belonging to genuine accounts, to automatically identify potential binge drinkers based only on linguistic features. On average, users classified as binge drinkers were quite similar to the standard genuine Twitter users in our sample. Nonetheless, the analysis of social media contents of genuine users reporting risky behaviours remains a promising source for informed preventive programs.

An Event-Related Potential Study of Decision-Making and Feedback Utilization in Female College Students Who Binge Drink

This study investigated the ability to use feedback for decision-making in female college students who binge drink (BD) using the iowa gambling task (IGT) and event-related potentials (ERPs). Twenty-seven binge drinkers and 23 non-binge drinkers (non-BD) were identified based on scores on the Korean version of the Alcohol Use Disorder Test and the Alcohol Use Questionnaire. The IGT consists of four cards, including two cards that result in a net loss, with large immediate gains but greater losses in the long term, and two cards that result in a net gain, with small immediate gains but reduced losses in the long term. Participants were required to choose one card at a time to maximize profit until the end of the task while avoiding losses. The BD group showed a significantly lower total net score than the non-BD group, indicating that the BD group chose more disadvantageous cards. The BD group showed significantly smaller ΔFRN amplitudes [difference in amplitudes of feedback-related negativity (FRN) between gain and loss feedback] but not in P3 amplitudes. Additionally, ΔFRN amplitudes in the fronto-central area were positively correlated with the total net score and net scores for sectors 4 and 5. Thus, total net scores and later performance on the IGT increased as ΔFRN amplitudes from the fronto-central area increased. FRN is known to reflect early feedback evaluation employing a bottom-up mechanism, whereas P3 is known to reflect late feedback processing and allocation of attentional resources using a top-down mechanism. These results indicate that college students who binge drink have deficits in early evaluation of positive or negative feedback and that this deficit may be related to decision-making deficits.

Perceived Social Support from Significant Others among Binge Drinking and Polyconsuming Spanish University Students

Sense of acceptance is conceived as a central component of perceived social support and is thought to be a key resilience factor for adjustment during transition to university. The current study examines how a binge drinking pattern of alcohol consumption and the co-consumption of binge drinking and cannabis in first-year university students are related to perceived acceptance from family, mother, father, and friends. The study sample consisted of 268 women and 216 men, of average age 18.25 years (SE = 0.01), enrolled in the first year of different degree courses at the University of Santiago de Compostela. Participants were classified in three groups (control, binge drinking, polyconsuming) on the basis of the Timeline Followback for alcohol and cannabis. Perceived sense of acceptance was measured using the Perceived Acceptance Scale. Analysis of the data revealed that perceived acceptance was lower in polyconsuming students than in the binge drinking and control groups (p < 0.05; with η2 ranging between 0.009 and 0.020). A curvilinear relationship between binge drinking and perceived acceptance from friends was identified. Social support should be considered in future investigations and interventions as a vulnerability marker for detrimental consequences of substance use and risk of consumption disorders, as well as adolescent maladjustment.

Auditing the AUDIT: A systematic review of cut-off scores for the Alcohol Use Disorders Identification Test (AUDIT) in low- and middle-income countries

INTRODUCTION

The World Health Organization's (WHO) Alcohol Use Disorders Identification Test (AUDIT) is used extensively across the world, with cut-off scores recommended by the WHO. We reviewed the use and validity of AUDIT cut-off scores in low- and middle-income countries as cultural contexts are expected to influence the detection of alcohol use disorders.

MATERIALS AND METHODS

The systematic review was guided by an a priori defined protocol consistent with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. We searched Cochrane library, Medline, EMBASE, PsycINFO, CINAHL, Indmed, LILACS, and AJOL databases using appropriate search terms. We conducted a narrative synthesis of the data.

RESULTS

We identified 54 distinct studies that used AUDIT cut-off scores which were not in alignment with those recommended by the WHO. India (n = 10), Nigeria (n = 9), and Brazil (n = 9) produced most of these included studies. Most of the studies (n = 42) did not conduct psychometric evaluations of AUDIT cut-off scores. Of the twelve studies which did report psychometric results, a wide range of cut-off scores performed well. In these studies the cut-off scores to detect hazardous drinking ranged from >3 to >5, for harmful drinking from >5 to >16, and for dependent drinking from >7 to >24.

DISCUSSION

AUDIT is being widely used in LMICs and non-recommended cut-off scores are considered to be appropriate in these countries. It is important to systematically evaluate the psychometric properties of those cut-off scores to ensure the internal validity of the studies in which they are used.

Young frequent binge drinkers show no behavioral deficits in inhibitory control and cognitive flexibility

Alcohol intoxication and abuse are well-known to cause impairments in executive functioning and control. Still, we know surprisingly little about individuals engaging in frequent binge drinking, even though they have an increased risk to develop an alcohol use disorder (AUD) later in life. As this risk has been suggested to be linked to (premorbid) executive deficits, we assessed changes in cognitive flexibility and inhibition with the help of a switching task and a stop-change task. Both paradigms had previously been shown to be modulated by alcohol, as well as by functional variations in dopaminergic and GABAergic neurotransmission. We employed an extreme group approach, where we compared pre-selected samples of frequent binge drinkers and non-frequent binge drinkers, all of which had stably pursued their respective consumption pattern for at least 3 years. In combination with Bayes analyses, our results showed that individuals engaging in frequent binge drinking showed no impairments of cognitive flexibility or inhibition, as compared to non-frequent binge drinkers. These observations suggest that frequent binge drinking alone is not associated with the cognitive control deficits commonly observed in AUD. Importantly, the investigated executive functions are known to be altered both during binge drinking and in individuals with AUD. It could hence be speculated that their intermittent consumption pattern prevents non-AUD frequent binge drinkers from the homeostatic counter-regulations of alcohol- and control-associated neurotransmitter systems that may be observed in AUD patients. Yet, this hypothesis still needs to be tested in future research, including studies that combine MR and molecular imaging.

Face validity of a pre-clinical model of operant binge drinking: just a question of speed

Binge drinking (BD) is often defined as a large amount of alcohol consumed in a 'short' period of time or 'per occasion'. In clinical research, few researchers have included the notion of 'speed of drinking' in the definition of BD. Here, we aimed to describe a novel pre-clinical model based on voluntary operant BD, which included both the quantity of alcohol and the rapidity of consumption. In adult Long-Evans male rats, we induced BD by regularly decreasing the duration of ethanol self-administration from 1-hour to 15-minute sessions. We compared the behavioral consequences of BD with the behaviors of rats subjected to moderate drinking or heavy drinking (HD). We found that, despite high ethanol consumption levels (1.2 g/kg/15 minutes), the total amounts consumed were insufficient to differentiate HD from BD. However, consumption speed could distinguish between these groups. The motivation to consume was higher in BD than in HD rats. After BD, we observed alterations in locomotor coordination in rats that consumed greater than 0.8 g/kg, which was rarely observed in HD rats. Finally, chronic BD led to worse performance in a decision-making task, and as expected, we observed a lower stimulated dopaminergic release within nucleus accumbens slices in poor decision makers. Our BD model exhibited good face validity and can now provide animals voluntarily consuming very rapidly enough alcohol to achieve intoxication levels and thus allowing the study of the complex interaction between individual and environmental factors underlying BD behavior.

A comparison of implicit and explicit reward learning in low risk alcohol users versus people who binge drink and people with alcohol dependence

Chronic alcohol use leads to specific neurobiological alterations in the dopaminergic brain reward system, which probably are leading to a reward deficiency syndrome in alcohol dependence. The purpose of our study was to examine the effects of such hypothesized neurobiological alterations on the behavioral level, and more precisely on the implicit and explicit reward learning. Alcohol users were classified as dependent drinkers (using the DSM-IV criteria), binge drinkers (using criteria of the USA National Institute on Alcohol Abuse and Alcoholism) or low-risk drinkers (following recommendations of the Scientific board of trustees of the German Health Ministry). The final sample (n = 94) consisted of 36 low-risk alcohol users, 37 binge drinkers and 21 abstinent alcohol dependent patients. Participants were administered a probabilistic implicit reward learning task and an explicit reward- and punishment-based trial-and-error-learning task. Alcohol dependent patients showed a lower performance in implicit and explicit reward learning than low risk drinkers. Binge drinkers learned less than low-risk drinkers in the implicit learning task. The results support the assumption that binge drinking and alcohol dependence are related to a chronic reward deficit. Binge drinking accompanied by implicit reward learning deficits could increase the risk for the development of an alcohol dependence.

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Alcohol dependent patients were impaired in implicit and explicit reward learning.

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Alcohol dependence may lead to implicit and explicit reward learning deficits.

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Binge drinkers learned less than low-risk drinkers in the implicit learning task.

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Binge drinking is related to implicit reward learning deficits.

Mindfulness-Based Relapse Prevention and Transcranial Direct Current Stimulation to Reduce Heavy Drinking: A Double-Blind Sham-Controlled Randomized Trial

BACKGROUND

Mindfulness-based relapse prevention (MBRP) and transcranial direct current stimulation (tDCS) have independently shown benefits for treating alcohol use disorder (AUD). Recent work suggests tDCS may enhance mindfulness. The combination of MBRP and tDCS may provide synergistic benefits and may target both behavioral and neurobiological dysfunctions in AUD. The goal of this double-blind sham-controlled randomized trial was to examine the efficacy of a rolling group MBRP treatment combined with tDCS among individuals interested in reducing their drinking.

METHODS

Individuals who were interested in reducing their alcohol use (n = 84; 40.5% female; mean age = 52.3; 98.9% with current AUD) were randomized to receive active (2.0 milliamps) or sham (0.0 milliamps) anodal tDCS (5 cm × 3 cm electrode) of the right inferior frontal gyrus with the 5 cm × 3 cm cathodal electrode applied to the left upper arm, combined with 8 weeks of outpatient MBRP rolling group treatment. Assessments were conducted at baseline, posttreatment, and 2 months following treatment. The primary outcome was drinks per drinking day, and secondary outcomes were percent heavy drinking days, self-reported craving, alcohol cue reactivity in an alcohol cue task, and response inhibition in a stop signal reaction time task.

RESULTS

Results indicated significant reductions in drinks per drinking day over time, B(SE) = -0.535 (0.16), p = 0.001, and a significant dose effect for number of groups attended, B(SE) = -0.259 (0.11), p = 0.01. There were also significant effects of time and dose for number of groups attended on secondary outcomes of percent heavy drinking days and alcohol cue reactivity. There were no effects of active versus sham tDCS on primary or secondary outcomes.

CONCLUSIONS

Findings from the current study provide initial support for the effectiveness of rolling group MBRP as an outpatient treatment for drinking reduction. The current study did not find additive effects of this tDCS protocol in enhancing MBRP among individuals with drinking reduction goals.

Effects of measurement timing on subgroup identification using growth mixture modeling: An empirical application to alcohol use

Growth mixture modeling (GMM) identifies latent classes exhibiting distinct longitudinal patterns on an outcome. Subgroups identified by GMM may be artifactually influenced by measurement timing (e.g., timing of the initial assessment, length of the interval from the first to the last assessment, and total number of assessments) as well as the theoretically posited developmental patterns of the behavior. The current study investigated this possibility using alcohol data from the 1997 National Longitudinal Survey of Youth (n = 2686; 49.44% female; 71.84% White). Three assessment configurations were examined: all 12 waves, first 6 waves, and last 7 waves. Five subgroups were identified using all 12 waves: Normative (71.33%), Low-Increasing (8.45%), Low-Steady (8.97%), High-Slowly Decreasing (7.67%), and Extreme-Sharply Decreasing (3.57%). When comparing participants' subgroup membership for all 12 waves to the first six waves, 14% of the sample was differentially classified. When comparing all 12 waves to the last seven waves, 62% of the sample was differentially classified. Alterations in the timing of the initial assessment had a substantial impact on latent class estimation, underscoring the importance of selecting the developmental window a priori based on theory and empirical knowledge. The time-bounded nature of mixture modeling solutions (i.e., a selected developmental window within the course of a phenomenon) suggests that the latent subgroups should not be interpreted as representing subgroups that are present in the population. Future directions and strategies for testing alternative interpretations are presented. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Behavioral and Cerebral Impairments Associated with Binge Drinking in Youth: A Critical Review

Binge drinking is a widespread alcohol consumption pattern in youth that is linked to important behavioral and cerebral impairments, in both the short and the long term. From a critical review of the current literature on this topic, we conclude that binge drinkers display executive impairments, cerebral modifications, and problems with emotion-related processes. Five key empirical and theoretical topics are discussed to pave the way for future research in the field: (1) the specificity of the brain modifications observed in binge drinkers that may index a compensatory mechanism or result from multiple withdrawals; (2) the nature of the relationship between binge drinking and impairments, suggesting reciprocal influences between excessive alcohol consumption and executive deficits; (3) the possible recovery of brain and cognitive functioning after the cessation of binge drinking; (4) the validity of the continuum hypothesis, suggesting links between binge drinking and severe alcohol use disorders; and (5) the existing strategies to reduce binge drinking habits or rehabilitate the associated cognitive deficits. Future perspectives are described in relation to the questions raised to identify the crucial variables to be addressed in research and clinical practice.

Driving After Drinking Alcohol Associated with Insufficient Sleep and Insomnia among Student Athletes and Non-Athletes

Introduction: The proportion of university/college students (UCS) consuming alcohol is similar to the number of those reporting poor sleep, at approximately 30%, the proportion being greater in student athletes (SA). What remains to be understood is if poor sleep potentiates risky behaviors. Objective: Our aim was to examine the association among sleep difficulties, insomnia symptoms, and insufficient sleep on the risk of driving under the influence of alcohol in a sample of UCS and whether these associations were more pertinent in SA. Methods: Data from the National University/College Health Assessment was used from the years 2011–2014. Questions on number of drinks consumed and behaviors such as driving after drinking alcohol were related to answers to questions pertaining to sleep difficulties, insufficient sleep, and insomnia symptoms. Results: Mean alcohol intake was of about 3 drinks; SA consumed significantly more than student non-athletes (SNA). Binge-drinking episodes were significantly higher among SA than SNA. Difficulty sleeping was associated with an increased likelihood of driving after any drinks and after 5 or more drinks in both groups, effects being stronger among SA. Insomnia was associated with an increased likelihood of driving after any drinks and after 5 or more drinks in SA and after 5 or more drinks in SNA. These effects were stronger among athletes. Conclusion: The present study found that self-reported difficulties sleeping, insomnia symptoms, and insufficient sleep are associated with driving after drinking alcohol. This relationship applied to driving after drinking any alcohol or binge drinking and was again stronger among SA than SNA.

Binge drinking is associated with reduced quality of life in young students: A pan-European study

BACKGROUND

Binge drinking (BD) is frequently observed in youth, with psychological and cognitive consequences, but its link with quality of life has been scarcely explored.

METHODS

Sociodemographic and alcohol consumption characteristics were collected in a cross-sectional survey including 15,020 European students. Health-related quality of life was assessed using the Alcohol Quality of Life Scale (AQoLS) measuring the self-reported negative impact of alcohol consumption. A flexible link function, using Bayesian P-splines, was used to study the relationship between alcohol-related quality of life and alcohol consumption.

RESULTS

A non-linear relationship between BD and AQoLS scores was identified, showing that: (1) For students presenting moderate BD pattern, alcohol consumption is related to a robust reduction in quality of life, this link remaining stable for students with more intense BD patterns; (2) BD are not strongly associated with social, personal, and work activities, but are linked to an increase in perceived loss of control over consumption; (3) Harmful or hazardous consumption is also related with a massive decrease in quality of life; (4) The strongest relationship between BD and impacted quality of life is found among males and Eastern European students.

CONCLUSIONS

These results demonstrate the importance of measuring the perceived relation between alcohol and quality of life, beyond the classically assessed consequences, as this relation is strong among young students. Prevention programs should take this into account, notably regarding the perceived loss of control over alcohol consumption, which constitutes a key factor for the emergence of severe alcohol-use disorders.

Ventral striatal response during decision making involving risk and reward is associated with future binge drinking in adolescents

Beginning to engage in heavy alcohol use during adolescence, as opposed to later in life, is associated with elevated risk for a variety of negative consequences, including the development of an alcohol use disorder. Behavioral studies suggest that poor decision making predicts alcohol use during adolescence; however, more research is needed to determine the neurobiological risk factors that underlie this association. Using functional magnetic resonance imaging, brain activation during decision making involving risk and reward was assessed in 47 adolescents (14-15 years old) with no significant history or alcohol or drug use. After baseline assessment, participants completed follow-up interviews every 3 months to assess the duration to onset of binge drinking. Adolescents who made a greater number of risky selections and had greater activation in the nucleus accumbens, precuneus, and occipital cortex during decision making involving greater potential for risk and reward began binge drinking sooner. Findings suggest that heightened activation of reward circuitry during decision making under risk is a neurobiological risk factor for earlier onset of binge drinking. Furthermore, brain activation was a significant predictor of onset to binge drinking, even after controlling for decision-making behavior, suggesting that neurobiological markers may provide additional predictive validity over behavioral assessments. Interventions designed to modify these behavioral and neurobiological risk factors may be useful for curbing heavy alcohol use during adolescence.

Affective impairments in binge drinking: Investigation through emotional facial expression decoding

OBJECTIVE

Binge drinking, an excessive alcohol consumption pattern frequently observed in young people, is known to be associated with psychological and cerebral deficits. While cognitive dysfunctions have been widely investigated, emotional abilities have scarcely been explored. Such an exploration would however offer a more exhaustive understanding of the deficits associated with binge drinking, as well as of the possible transition towards alcohol-dependence.

METHODS

46 young adults (23 binge drinkers, 12 women; 23 control participants, 12 women) were recruited among university students. They performed an emotional recognition task consisting of the visual decoding of six basic emotions (i.e. anger, contempt, disgust, fear, happiness, and sadness). Accuracy scores and detection thresholds were collected for each emotion.

RESULTS

Binge drinkers showed lower performance than control participants for the decoding of all emotions and increased detection threshold, this later reflecting less ability to capture an emotion. Binge drinking is thus associated with a need for higher emotional intensity to perform correct detection. Moreover, these emotional difficulties appear specifically related to alcohol consumption.

CONCLUSION

These findings reinforce previous experimental evidence of altered emotional processing among binge drinkers, and extend these results for various emotional contents. They support the hypothesis of a continuum between binge drinking and alcohol-dependence, in which massive emotional impairments have been documented. Indeed, these impairments could be involved in the onset and maintenance of excessive alcohol consumption, notably through the established relationship between emotional deficits and social distress.

Presence and User Experience in a Virtual Environment under the Influence of Ethanol: An Explorative Study

Virtual Reality (VR) is used for a variety of applications ranging from entertainment to psychological medicine. VR has been demonstrated to influence higher order cognitive functions and cortical plasticity, with implications on phobia and stroke treatment. An integral part for successful VR is a high sense of presence - a feeling of 'being there' in the virtual scenario. The underlying cognitive and perceptive functions causing presence in VR scenarios are however not completely known. It is evident that the brain function is influenced by drugs, such as ethanol, potentially confounding cortical plasticity, also in VR. As ethanol is ubiquitous and forms part of daily life, understanding the effects of ethanol on presence and user experience, the attitudes and emotions about using VR applications, is important. This exploratory study aims at contributing towards an understanding of how low-dose ethanol intake influences presence, user experience and their relationship in a validated VR context. It was found that low-level ethanol consumption did influence presence and user experience, but on a minimal level. In contrast, correlations between presence and user experience were strongly influenced by low-dose ethanol. Ethanol consumption may consequently alter cognitive and perceptive functions related to the connections between presence and user experience.

Effects of Binge Drinking on the Developing Brain

Binge drinking is a pattern of alcohol drinking that raises a person's blood alcohol concentration to at least .08%, which amounts to consuming five alcoholic drinks for men and four alcoholic drinks for women in about 2 hours. It is the most common form of alcohol misuse in adolescents and young adults. Heavy drinking includes the same criterion as binge drinking, but with higher frequency (i.e., 5 or more days in the past 30 days). Although binge drinking or heavy drinking alone is insufficient to meet the criteria for an alcohol use disorder (AUD) diagnosis, there are neurobiological changes, as well as an increased risk of developing an AUD later in life, associated with this form of alcohol misuse. This review describes the recent neuroimaging findings in binge drinking and heavy-drinking adolescents and young adults, a developmental period during which significant neuromaturation occurs.

Gender Differences in Binge Drinking

Just as binge drinking rates differ for men and women, the predictors and consequences of binge drinking vary by gender as well. This article examines these differences and how binge drinking definitions and research samples and methods may influence findings. It also describes the relationship between age and binge drinking among men and women, and how drinking culture and environment affect this relationship. It examines gender-specific trends in binge drinking, predictors of binge drinking for men and women, and binge drinking in the context of smoking. The article reviews current findings on gender differences in the health consequences of binge drinking, including morbidity and mortality, suicidality, cancer, cardiovascular disorders, liver disorders, and brain and neurocognitive implications. It also discusses gender differences in the behavioral and social consequences of binge drinking, including alcohol-impaired driving, sexual assault, and intimate partner violence, and includes implications for treatment and prevention.

Role of the innate immune system in the neuropathological consequences induced by adolescent binge drinking

Adolescence is a critical stage of brain maturation in which important plastic and dynamic processes take place in different brain regions, leading to development of the adult brain. Ethanol drinking in adolescence disrupts brain plasticity and causes structural and functional changes in immature brain areas (prefrontal cortex, limbic system) that result in cognitive and behavioral deficits. These changes, along with secretion of sexual and stress-related hormones in adolescence, may impact self-control, decision making, and risk-taking behaviors that contribute to anxiety and initiation of alcohol consumption. New data support the participation of the neuroimmune system in the effects of ethanol on the developing and adult brain. This article reviews the potential pathological bases that underlie the effects of alcohol on the adolescent brain, such as the contribution of genetic background, the perturbation of epigenetic programming, and the influence of the neuroimmune response. Special emphasis is given to the actions of ethanol in the innate immune receptor toll-like receptor 4 (TLR4), since recent studies have demonstrated that by activating the inflammatory TLR4/NFκB signaling response in glial cells, binge drinking of ethanol triggers the release of cytokines/chemokines and free radicals, which exacerbate the immune response that causes neuroinflammation/neural damage as well as short- and long-term neurophysiological, cognitive, and behavioral dysfunction. Finally, potential treatments that target the neuroimmune response to treat the neuropathological and behavioral consequences of adolescent alcohol abuse are discussed.

A Personalidade na Tomada de Decisão com o Iowa Gambling Task: Uma Revisão Integrativa

RESUMO O Iowa GamblingTask (IGT), apesar de amplamente utilizado na avaliação da tomada de decisão, apresenta uma grande variabilidade nos resultados. Pretende-se com este trabalho proceder a uma revisão integrativa da literatura que relacione a personalidade com o desempenho no IGT, de modo a identificar o papel dessa variável nesse desempenho. Para o efeito, foram selecionados e analisados 74 estudos referenciados na Web of Science e na b-on. Os resultados evidenciam alguma inconsistência e algumas relações não lineares entre variáveis, embora o mau desempenho no IGT surja associado mais frequentemente à dimensão neuroticismo, ansiedade, impulsividade, variáveis socioeconômicas e ao fator antissociabilidade na psicopatia e dependência de substâncias. À luz desses resultados, sugerem-se algumas orientações para a pesquisa na área.

Gender differences in the inflammatory cytokine and chemokine profiles induced by binge ethanol drinking in adolescence

Heavy binge drinking in adolescence can cause long-term cognitive and behavioral dysfunctions. Recent experimental evidence indicates the participation of immune system activation in the effects of ethanol in the adolescent brain and suggests gender differences. The present study aims to assess plasma cytokine and chemokine levels in male and female adolescents and young adults during acute alcohol intoxication and to correlate these results with the toll-like receptor 4 (TLR4) response. The potential role of the TLR4 signaling response was also assessed in plasma and prefrontal cortex (PFC) of adolescent wild-type and TLR4-knockout male and female mice with binge ethanol treatment. The results showed that alcohol intoxication increased the plasma levels of several cytokine and chemokine [interferon-γ, interleukin (IL)-10, IL-17A, IL-1β, IL-2, IL-4, IL-6, IL-8, fractalkine, monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein 1α (MIP-1α)] and the upregulation of TLR4 mRNA levels occurred in intoxicated females, while elevation of colony-stimulating factor was only observed in the plasma of males. In wild-type female adolescent mice, intermittent ethanol treatment increased the levels of several cytokines (IL-17A and IL-1β) and chemokines (MCP-1, MIP-1α and fractalkine) in PFC and in serum (IL-17A, MCP-1 and MIP-1α), but significant differences in the fractalkine levels in PFC were observed only in male mice. No changes in serum or prefrontal cortex cytokine and chemokine levels were noted in ethanol-treated male or female TLR4-knockout mice. Our findings revealed that females are more vulnerable than males to inflammatory effects of binge ethanol drinking and suggested that TLR4 is an important target of ethanol-induced inflammation and neuroinflammation in adolescence.

Alcohol Binge Drinking and Executive Functioning during Adolescent Brain Development

Alcohol consumption in adolescents causes negative effects on familiar, social, academic life, as well as neurocognitive alterations. The binge drinking (BD) pattern of alcohol is characterized by the alternation of episodes of heavy drinking in a short interval of time, and periods of abstinence, a practice that can result in important brain alterations; even more than regular alcohol consumption. The prefrontal cortex, which acts as neural support for the executive processes, is particularly affected by alcohol; however, not all studies are in agreement about how BD alcohol consumption affects executive functioning. Some research has found that alcohol consumption in adolescence does not significantly affect executive functioning while others found it does. It is possible that these discrepancies could be due to the history of alcohol consumption, that is, at what age the subjects started drinking. The aim of our study is to assess the performance on executive functioning tasks of 13–19-year-old adolescents according to their pattern of alcohol consumption. We hypothesize that BD adolescents will perform worse than non-BD subjects in tasks that evaluate executive functions, and these differences will increase depending on how long they have been consuming alcohol. Three hundred and twenty-two students (48.14% females; age range 13–22 years; mean aged 16.7 ± 2.59) participated in the study; all of them had begun drinking at the age of 13 years. Participant were divided into three groups, according to their age range (13–15, 16–18, and 19–22 years) and divided according to their pattern of alcohol consumption (BD and control groups). Then, the subjects were evaluated with neuropsychological tasks that assess executive functions like working memory, inhibition, cognitive flexibility, or self-control among others. The entire sample showed a normal improvement in their executive performance, but this improvement was more stable and robust in the control group. Regarding the executive performance among age groups, control subjects only obtained better results than BDs in the 19–22-year-old range, whereas the performance was quite similar at younger ages. Considering that all the BD subjects started drinking at the same age (13 years old), it is possible that a kind of compensation mechanism exists in the adolescent brain which allows them to reach a normal performance in executive tasks. This theoretical mechanism would depend upon neuronal labor, which could lose efficacy over time with further alcohol ingestion. This process would account for the differences in neuropsychological performance, which were only observed in older students with a longer history of alcohol consumption.

Age of Drinking Initiation as a Risk Factor for Alcohol Use Disorder Symptoms is Moderated by ALDH2*2 and Ethnicity

BACKGROUND

An early age of drinking initiation (ADI) has been associated with increased risk for alcohol use disorders (AUDs), but the consistency of this risk across diverse samples has not been well studied. The purpose of this study was to examine whether the pathway from ADI to AUD symptoms by early adulthood is moderated by ethnicity and possessing an alcohol-metabolizing gene ALDH2*2 variant allele.

METHODS

We used multigroup structural equation modeling, including 5 groups split by ethnicity and ALDH2*2, to examine the consistency of the path from ADI to AUD symptoms in 604 Chinese-, Korean-, and White-American college students. We further examined the effects of ALDH2*2, ethnicity, and their interaction in Asians to better understand their unique contributions to the moderation.

RESULTS

The association between ADI and AUD symptoms was moderated, with ADI negatively associated with AUD symptoms among Koreans without ALDH2*2 and Whites, but not among Koreans with ALDH2*2 or Chinese regardless of ALDH2*2. Both ALDH2*2 and ethnicity within Asians contributed unique variability in the effect.

CONCLUSIONS

Ethnicity and ALDH2*2 altered the relationship of ADI as a risk factor for AUD symptoms. Being Chinese and possessing an ALDH2*2 allele within Koreans both buffered against the risk for AUD symptoms associated with earlier ADI, indicating that this relationship can be attenuated by protective factors.