Pathways to alcohol-induced brain impairment in young people: a review by Hermens et al., 2013

What is binge drinking? Insights from a network perspective

This study aimed to delineate the specific characteristics of binge drinking habits by capitalizing on data-driven network analysis. Such an approach allowed us to consider binge drinking as a network system of interacting elements, thus identifying the key variables involved in this phenomenon. A total of 1,455 university students with excessive drinking habits were included in this study. We assessed the most critical features of binge drinking (i.e., the consumption of more than six alcohol units per occasion, drunkenness frequency, consumption speed), together with alcohol use and more general alcohol-related components of dysfunction and harm. All variables were considered in the network analysis. Centrality analysis identified drunkenness frequency as the most influential variable in the entire network. Community detection analysis showed three distinct subnetworks related to alcohol use, drunkenness, and dysfunction/harm components. Drunkenness frequency and blackout occurrence emerged as core bridge items in the binge drinking network. Drunkenness is recognized as the hallmark feature of binge drinking.

Emotional processes in binge drinking: A systematic review and perspective

Binge drinking is a widespread alcohol consumption pattern commonly engaged by youth. Here, we present the first systematic review of emotional processes in relation to binge drinking. Capitalizing on a theoretical model describing three emotional processing steps (emotional appraisal/identification, emotional response, emotional regulation) and following PRISMA guidelines, we considered all identified human studies exploring emotional abilities among binge drinkers. A literature search was conducted in PubMed, Scopus, and PsychINFO, and a standardized methodological quality assessment was performed for each study. The main findings offered by the 43 studies included are: 1) regarding emotional appraisal/identification, binge drinking is related to heightened negative emotional states, including greater severity of depressive and anxiety symptoms, and have difficulties in recognizing emotional cues expressed by others; 2) regarding emotional response, binge drinkers exhibit diminished emotional response compared with non-binge drinkers; 3) regarding emotional regulation, no experimental data currently support impaired emotion regulation in binge drinking. Variability in the identification and measurement of binge drinking habits across studies limits conclusions. Nevertheless, current findings establish the relevance of emotional processes in binge drinking and set the stage for new research perspectives to identify the nature and extent of emotional impairments in the onset and maintenance of excessive alcohol use.

Can we boost attention and inhibition in binge drinking? Electrophysiological impact of neurocognitive stimulation

RATIONALE

Binge drinking (i.e. excessive episodic alcohol consumption) among young adults has been associated with deleterious consequences, notably at the cognitive and brain levels. These behavioural impairments and brain alterations have a direct impact on psychological and interpersonal functioning, but they might also be involved in the transition towards severe alcohol use disorders. Development of effective rehabilitation programs to reduce these negative effects as they emerge thus constitutes a priority in subclinical populations.

OBJECTIVES

The present study tested the behavioural and electrophysiological impact of neurocognitive stimulation (i.e. transcranial direct current stimulation (tDCS) applied during a cognitive task) to improve attention and inhibition abilities in young binge drinkers.

METHODS

Two groups (20 binge drinkers and 20 non-binge drinkers) performed two sessions in a counterbalanced order. Each session consisted of an inhibition task (i.e. Neutral Go/No-Go) while participants received left frontal tDCS or sham stimulation, immediately followed by an Alcohol-related Go/No-Go task, while both behavioural and electrophysiological measures were recorded.

RESULTS

No significant differences were observed between groups or sessions (tDCS versus sham stimulation) at the behavioural level. However, electrophysiological measurements during the alcohol-related inhibition task revealed a specific effect of tDCS on attentional resource mobilization (indexed by the N2 component) in binge drinkers, whereas later inhibition processes (indexed by the P3 component) remained unchanged in this population.

CONCLUSIONS

The present findings indicate that tDCS can modify the electrophysiological correlates of cognitive processes in binge drinking. While the impact of such brain modifications on actual neuropsychological functioning and alcohol consumption behaviours remains to be determined, these results underline the potential interest of developing neurocognitive stimulation approaches in this population.

Disentangling the role of social cognition processes at early steps of alcohol abuse: The influence of affective theory of mind

Excessive alcohol use among adolescents has become a pressing challenge among Western societies. Accordingly, one of the current research objectives is to identify the processes associated with this harmful habit. Although numerous studies have underlined the role of executive and motivational processes, few have explored emotional and interpersonal abilities at early steps of alcohol abuse. The present study evaluated the role of two social cognition processes, namely theory of mind (ability to infer others' mental states at cognitive and affective levels) and empathy (ability to understand others' feelings at cognitive and affective levels) in adolescents' alcohol consumption. Two hundred and two adolescents (13-20 years old) performed a behavioral task evaluating theory of mind and filled in questionnaires measuring personal data, empathy, alcohol consumption (alcohol abuse and specific binge drinking), as well as depressive and anxiety symptoms. Findings showed that cognitive and affective empathy were negatively associated with alcohol consumption in youth whereas affective theory of mind was related to specific binge drinking. Importantly, affective theory of mind predicted binge drinking in adolescents, even after controlling for age, gender, and education level. These results emphasized the role of social cognition in early alcohol abuse and showed that, beyond inhibition, interpersonal abilities might precipitate excessive drinking in youth.

Electrophysiological correlates of emotional crossmodal processing in binge drinking

Emotional crossmodal integration (i.e., multisensorial decoding of emotions) is a crucial process that ensures adaptive social behaviors and responses to the environment. Recent evidence suggests that in binge drinking-an excessive alcohol consumption pattern associated with psychological and cerebral deficits-crossmodal integration is preserved at the behavioral level. Although some studies have suggested brain modifications during affective processing in binge drinking, nothing is known about the cerebral correlates of crossmodal integration. In the current study, we asked 53 university students (17 binge drinkers, 17 moderate drinkers, 19 nondrinkers) to perform an emotional crossmodal task while their behavioral and neurophysiological responses were recorded. Participants had to identify happiness and anger in three conditions (unimodal, crossmodal congruent, crossmodal incongruent) and two modalities (face and/or voice). Binge drinkers did not significantly differ from moderate drinkers and nondrinkers at the behavioral level. However, widespread cerebral modifications were found at perceptual (N100) and mainly at decisional (P3b) stages in binge drinkers, indexed by slower brain processing and stronger activity. These cerebral modifications were mostly related to anger processing and crossmodal integration. This study highlights higher electrophysiological activity in the absence of behavioral deficits, which could index a potential compensation process in binge drinkers. In line with results found in severe alcohol-use disorders, these electrophysiological findings show modified anger processing, which might have a deleterious impact on social functioning. Moreover, this study suggests impaired crossmodal integration at early stages of alcohol-related disorders.

Impact of Exchange Stay on Alcohol Consumption: Longitudinal Exploration in a Large Sample of European Students

BACKGROUND

Each year, more than 300,000 university students take part in European exchange programs. Besides their positive educational and cultural impacts, these programs are also reputed to immerse students in a high-risk festive context where excessive alcohol consumption is strongly present. There is thus a crucial need to evaluate the actual impact of those exchange stays on alcohol consumption.

METHODS

Study abroad (n = 3,950) and local (n = 3,950) European students completed a 2-part longitudinal survey and reported their alcohol consumption before (T1) and during (T2) their exchange stay (or at the beginning of the academic year and 6 months later for local students, constituting the control group).

RESULTS

During their exchange stay, individuals studying abroad showed more excessive and harmful alcohol consumption behaviors than local students, as measured by increased general alcohol consumption and binge drinking (BD) scores at T2. In particular, study abroad students under 20 years of age and performing their exchange stay in eastern Europe were the most exposed to excessive alcohol consumption and BD.

CONCLUSIONS

These results constitute the first large-scale longitudinal confirmation that exchange stays indeed constitute risky contexts in which students significantly increase their consumption and present stronger alcohol-related problems. In view of the rapid and deleterious effects of alcohol consumption in young people, it is essential to promote prevention campaigns targeting this population to limit public health consequences and possible evolution toward severe alcohol use disorders.

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.

Enhancement motivation to drink predicts binge drinking in adolescence: a longitudinal study in a community sample

BACKGROUND

Binge drinking, characterized by alternations between intense alcohol intakes and abstinence periods, is the most frequent alcohol-consumption pattern among adolescents and is associated with cognitive impairments.

OBJECTIVES

It appears crucial to disentangle the psychological factors involved in the emergence of binge drinking in adolescence, and centrally the role played by drinking motives, which are related to binge drinking.

METHODS

This longitudinal study explored the role of drinking motives (i.e., social order, conformity, enhancement, coping) in the emergence of binge drinking among 144 adolescents (56.3% girls) from the community, who were assessed for alcohol consumption and drinking motives at two times (T1/T2), with a 1-year interval. After data checking, 101 adolescents (12-15 years old; 56.4% girls) constituted the final sample.

RESULTS

Strong relationships were found between drinking motives and binge drinking. Regression analyses were computed to determine how drinking motives at T1 predicted binge drinking at T2, while controlling for global alcohol use. The statistical model explained 60% of the binge-drinking variance. In particular, enhancement motivation (i.e., the search for the enjoyable sensations felt when drinking) constituted the unique predictor of future binge drinking. Conversely, social motives did not predict binge drinking.

CONCLUSION

These findings highlight the central role of enhancement motivation (e.g., focusing on the positive expectancies towards alcohol) in youths' alcohol consumption and call for the development of preventive interventions. The previously reported relationship between social motives and college drinking does not seem to play a key role in the early steps of binge drinking.

Identifying Inhibitory Subcomponents Associated with Changes in Binge Drinking Behavior: A 6-Month Longitudinal Design

BACKGROUND

Links between response inhibition and young adult problematic drinking (e.g., binge drinking) have been established, but only to an extent. Considering the presence of some inconsistent findings associated with these 2 variables, this study proposes the need to investigate the extent in which different inhibitory subcomponents are associated with binge drinking behaviors of the same sample.

METHODS

Through the use of a 6-month longitudinal design, changes in Alcohol Use Questionnaire (AUQ) binge score of 163 college students (50.3% female) with a mean age of 21.06 years (SD = 1.83) were correlated with performance on 3 different inhibitory control tasks. Each task was selected to assess separate inhibitory subcomponents: Stop Signal Task (e.g., cancellation of a response), Go/No-Go Task (e.g., withholding of a response), and Simon Task (e.g., inhibiting response interference). Response inhibition was also compared between 2 groups, those who had a substantial increase in AUQ binge score during participation (inAUQ) and those who had a substantial decrease in AUQ binge score (deAUQ).

RESULTS

A significant correlation was found with a change in AUQ binge score and stop signal reaction time among females only, where an increase in binge drinking score positively correlated with a reduced ability to cancel an already-initiated inhibitory response. Differences in inhibitory performance, where inAUQ performed worse than deAUQ, approached significance.

CONCLUSIONS

The results suggest that the cancellation of a prepotent response, as opposed to the withholding of response or interference inhibition, is a more sensitive inhibitory measure associated with increases in binge drinking behavior among female young adult college students. Further exploration of inhibitory subcomponents relative to substance use is greatly needed (e.g., more extensive longitudinal designs and neuroimaging techniques).

Attentional and Neural Processing of Affective and Alcohol-Related Images in University-Attending Emerging Adults

High-risk drinking is prevalent in university-attending emerging adults. This coincides with a critical time for the development of higher level cognitive and emotional processing and underlying neurobiological mechanisms. Cognitive and emotional processing seems to have a particularly sensitive relationship with alcohol. The current study sought to examine the relationship between alcohol use and neurophysiology in an emerging adult, university-attending population. Neurophysiological response, defined as event-related potentials, to alcohol-related and emotionally affective images were evaluated in 23 drinkers and 21 nondrinkers. Drinkers had a greater attentional response to alcohol, positive, and negative images compared to nondrinkers. No differences were found between groups for attentional response (P2) to neutral images or for later emotional processing (late positive potential) for any stimuli type. These data suggest that this drinking population processes alcohol stimuli and affective images similarly and more robustly than nondrinking peers. These data support a relationship between alcohol and emotional processing in emerging adults.

Preserved Crossmodal Integration of Emotional Signals in Binge Drinking

Binge drinking is an alcohol consumption pattern with various psychological and cognitive consequences. As binge drinking showed qualitatively comparable cognitive impairments to those reported in alcohol-dependence, a continuum hypothesis suggests that this habit would be a first step toward alcohol-related disorders. Besides these cognitive impairments, alcohol-dependence is also characterized by large-scale deficits in emotional processing, particularly in crossmodal contexts, and these abilities have scarcely been explored in binge drinking. Emotional decoding, most often based on multiple modalities (e.g., facial expression, prosody or gesture), yet represents a crucial ability for efficient interpersonal communication and social integration. The present study is the first exploration of crossmodal emotional processing in binge drinking, in order to test whether binge drinkers already present the emotional impairments described among alcohol-dependent patients, in line with the continuum hypothesis. Twenty binge drinkers and 20 matched controls performed an experimental task requiring the identification of two emotions (happiness or anger) presented in two modalities (visual or auditory) within three conditions (unimodal, crossmodal congruent or crossmodal incongruent). In accordance with previous research in binge drinking and alcohol-dependence, this study was based on two main hypotheses. First, binge drinkers would present a reduced facilitation effect (i.e., classically indexed in healthy populations by faster reaction times when two congruent modalities are presented simultaneously). Second, binge drinkers would have higher difficulties to inhibit interference in incongruent modalities. Results showed no significant difference between groups in emotional decoding ability, whatever the modality or condition. Control participants, however, appeared slower than binge drinkers in recognizing facial expressions, also leading to a stronger facilitation effect when the two modalities were presented simultaneously. However, findings did not show a disrupted facilitation effect in binge drinkers, whom also presented preserved performance to inhibit incongruence during emotional decoding. The current results thus suggest that binge drinkers do not demonstrate a deficit for emotional processing, both in unimodal and crossmodal contexts. These results imply that binge drinking might not be characterized by impairments for the identification of primary emotions, which could also indicate that these emotional processing abilities are well-preserved at early stages of excessive alcohol consumption.

Differential impairments across attentional networks in binge drinking

RATIONALE

The cognitive deficits observed in young binge drinkers have been largely documented during the last decade. Yet, these earlier studies have mainly focused on high-level cognitive abilities (particularly memory and executive functions), and uncertainty thus still abounds regarding the integrity of less complex cognitive processes in binge drinking. This is particularly true for attentional abilities, which play a crucial role in behavior regulation and are impaired in other alcohol-related disorders.

OBJECTIVES AND METHODS

To specify the attentional deficits associated with binge drinking, two groups of university students (40 binge drinkers and 40 matched controls) performed the Attention Network Task, a theoretically grounded test assessing three independent attentional networks: alerting, orienting, and executive control.

RESULTS

Binge drinkers displayed preserved orienting performance but impaired alerting and executive control. Binge drinking is thus not related to a general attentional impairment but rather to specific impairments of the alerting and executive control networks.

CONCLUSIONS

These results underline that, beyond the already explored high-level deficits, binge drinking is also related to impairments for attentional abilities. In view of the role played by attentional impairments in alcohol dependence, the present data also suggest that rehabilitation programs should be developed to improve attentional abilities at the early stages of alcohol-related disorders.

Evolution of the binge drinking pattern in college students: neurophysiological correlates

It is well known that alcohol impairs response inhibition and that adolescence is a critical period of neuromaturation where cognitive processes such as inhibitory control are still developing. In recent years, growing evidence has shown the negative consequences of alcohol binge drinking on the adolescent and young human brain. However, the effects of cessation of binge drinking on brain function remain unexplored. The objective of the present study was to examine brain activity during response execution and inhibition in young binge drinkers in relation to the progression of their drinking habits over time. Event-related potentials (ERPs) elicited by a Go/NoGo task were recorded twice within a 2-year interval in 57 undergraduate students (25 controls, 22 binge drinkers, and 10 ex-binge drinkers) with no personal or family history of alcoholism or psychopathological disorders. The results showed that the amplitude of NoGo-P3 over the frontal region correlated with an earlier age of onset of regular drinking as well as with greater quantity and speed of alcohol consumption. Regression analysis showed that NoGo-P3 amplitude was significantly predicted by the speed of alcohol intake and the age of onset of regular drinking. The group comparisons showed that, after maintaining a binge drinking pattern for at least 2 years, binge drinkers displayed significantly larger NoGo-P3 amplitudes than controls, whereas ex-binge drinkers were in an intermediate position between the two other groups (with no significant differences with respect to controls or binge drinkers). These findings suggest that binge drinking in young people may impair the neural functioning related to inhibitory processes, and that the cessation of binge drinking may act as a brake on the neurophysiological impairments related to response inhibition.

Larger mid-dorsolateral prefrontal gray matter volume in young binge drinkers revealed by voxel-based morphometry

Binge drinking or heavy episodic drinking is a high prevalent pattern of alcohol consumption among young people in several countries. Despite increasing evidence that binge drinking is associated with impairments in executive aspects of working memory (i.e. self-ordered working memory), processes known to depend on the mid-dorsolateral prefrontal cortex (Brodmann areas 46 and 9), less is known about the impact of binge drinking on prefrontal gray matter integrity. Here, we investigated the effects of binge drinking on gray matter volume of mid- dorsolateral prefrontal cortex in youths. We used voxel-based morphometry on the structural magnetic resonance images of subjects reporting a persistent (at least three years) binge drinking pattern of alcohol use (n = 11; age 22.43 ± 1.03) and control subjects (n = 21; age 22.18 ± 1.08) to measure differences in gray matter volume between both groups. In a region of interest analysis of the mid-dorsolateral prefrontal cortex, after co-varying for age and gender, we observed significantly larger gray matter volume in the left mid-dorsolateral prefrontal cortex (Brodmann areas 46 and 9) in binge drinkers in comparison with control subjects. Furthermore, there was a significant positive correlation between left mid-dorsolateral prefrontal cortex volume and Self-Ordered Pointing Test (SOPT) total errors score in binge drinkers. The left mid-dorsolateral prefrontal cortex volume also correlated with the quantity and speed of alcohol intake. These findings indicate that a repeated exposure to alcohol -that does not meet criteria for alcohol dependence- throughout post-adolescent years and young adulthood is linked with structural anomalies in mid-dorsolateral prefrontal regions critically involved in executive aspects of working memory.

Why is adolescence a key period of alcohol initiation and who is prone to develop long-term problem use?: A review of current available data

BACKGROUND

Early adolescence is a key developmental period for the initiation of alcohol use, and consumption among adolescents is characterized by drinking in high quantities. At the same time, adolescence is characterized by rapid biological transformations including dramatic changes in the brain, particularly in the prefrontal cortex and the mesocorticolimbic dopamine system.

METHODS

This article begins with an overview of the unique neural and behavioural characteristics of adolescent development that predispose these individuals to seek rewards and take risks such as initiation of drinking and high levels of alcohol intake. The authors then outline important factors associated with an increased risk for developing alcohol problems in later adolescence and young adulthood. Thereafter they address causality and the complex interplay of risk factors that lead to the development of alcohol use problems in late adolescence and young adults.

CONCLUSIONS

A few recommendations for the prevention of underage drinking are presented.

Increased cortical activity in binge drinkers during working memory task: a preliminary assessment through a functional magnetic resonance imaging study

BACKGROUND

Cerebral dysfunction is a common feature of both chronic alcohol abusers and binge drinkers. Here, we aimed to study whether, at equated behavioral performance levels, binge drinkers exhibited increased neural activity while performing simple cognitive tasks.

METHODS

Thirty-two participants (16 binge drinkers and 16 matched controls) were scanned using functional magnetic resonance imaging (fMRI) while performing an n-back working memory task. In the control zero-back (N0) condition, subjects were required to press a button with the right hand when the number "2" was displayed. In the two-back (N2) condition, subjects had to press a button when the displayed number was identical to the number shown two trials before.

RESULTS

fMRI analyses revealed higher bilateral activity in the pre-supplementary motor area in binge drinkers than matched controls, even though behavioral performances were similar. Moreover, binge drinkers showed specific positive correlations between the number of alcohol doses consumed per occasion and higher activity in the dorsomedial prefrontal cortex, as well as between the number of drinking occasions per week and higher activity in cerebellum, thalamus and insula while performing the N2 memory task.

CONCLUSIONS

Binge alcohol consumption leads to possible compensatory cerebral changes in binge drinkers that facilitate normal behavioral performance. These changes in cerebral responses may be considered as vulnerability factors for developing adult substance use disorders.