Blood Alcohol Concentration-Related Lower Performance in Immediate Visual Memory and Working Memory in Adolescent Binge Drinkers

Alcohol Intake and Academic Performance and Dropout in High School: A Prospective Cohort Study in 65,233 Adolescents

PURPOSE

During the teenage years, many adolescents start drinking alcohol, and binge drinking is prevalent. We investigated the relationship between alcohol intake and academic performance.

METHODS

We conducted a longitudinal cohort study by combining data from the Danish National Youth Study on 65,233 high school students aged 15-20 years, with information on dropout and grade point average. We assessed associations between alcohol intake and academic performance using multilevel Poisson regression and linear regression, accounting for dependency between students from the same school and class.

RESULTS

The average alcohol intake was 10 drinks per week, and 43.6% engaged in binge drinking 3+ times per month. During follow-up, 9.8% of the boys and 6.7% of the girls dropped out. The incidence rate ratio was higher in never drinkers, frequent binge drinkers, and those with a high weekly alcohol intake as compared to those with a low intake. For example, the incidence rate ratio was 1.47 (95% confidence level: 1.24, 1.76) in girls who drank 21-27 drinks per week and 1.29 (95% confidence level: 1.13, 1.48) in girls who never drank as compared to those who drank <7 drinks per week. Alcohol associated with a lower grade point average over the entire span of intake in a dose-dependent manner, and similarly so in boys and girls. Findings were consistent in strata of socioeconomy and individual academic ambition.

DISCUSSION

Alcohol intake has implications for academic performance and poses a threat for the prospects of the individual as well as society. Policies and interventions aimed at lowering the intake among high school students are warranted.

Associations between blackout drinking and self-reported everyday cognition among young adults

INTRODUCTION

Blackout drinking, or alcohol-induced memory loss during at least some part of a drinking occasion, is common among young adults and associated with negative alcohol-related consequences. One potential unique effect of blackout drinking episodes could be prolonged, general difficulties forming new memories through impairments in encoding, storage, or retrieval. The current study examined preliminary associations between blackout drinking and self-reported everyday cognitive functioning (i.e., memory lapses, non-memory cognitive difficulties, cognitive concerns) among a sample of young adults. We also examined the moderating role of key factors linked to blackout drinking: gender and frequent simultaneous alcohol and cannabis use.

METHODS

Participants (N = 479; 53% women) were aged 18-30 who reported past-year blackout drinking. Participants completed an online survey through Qualtrics Panels.

RESULTS

More frequent blackout experiences were found to be significantly related to more memory lapses, more non-memory cognitive difficulties, and more cognitive concerns even after controlling for typical alcohol use behavior. Men and individuals reporting frequent simultaneous use indicated stronger relationships between blackout drinking frequency and cognitive outcomes.

DISCUSSION AND CONCLUSIONS

Findings add to the growing body of literature supporting the uniquely hazardous effects of blackout drinking and identify individuals at heightened risk of harms. Given that associations between blackout drinking frequency and everyday cognitive functioning were identified even among a young adult sample suggests that blackout drinking may be a risky behavior that links to poorer cognitive functioning.

The Influence of Sex on Hippocampal Neurogenesis and Neurotrophic Responses on the Persistent Effects of Adolescent Intermittent Ethanol Exposure into Adulthood

In the United States, approximately 90% of alcohol consumed by adolescents is binge drinking. Binge-like ethanol exposure during adolescence promotes dysregulation of neurotrophic responses and neurogenesis in the hippocampus. These effects include changes in proliferation, regulation, differentiation, and maturation of neurons, and there is indication that such effects may be disproportionate between sexes. This study determined whether sex impacts neurotrophic responses and neurogenesis in adulthood after adolescent intermittent ethanol (AIE) exposure. To determine this, adolescent rats underwent AIE with ethanol (5 g/kg). In adulthood, animals were euthanized, and immunohistochemical techniques and ELISAs were utilized to determine AIE effects on sex-specific neurogenesis factors and neurotrophic markers, respectively. AIE exposure led to a significant decrease in neurogenesis in the dentate gyrus of the hippocampal formation indicated by reductions in the numbers of DCX+, SOX2+ and Ki-67+ cells in male and female AIE-exposed rats. Additionally, AIE increased markers for the pro-inflammatory cytokines, TNF-α and IL-1β, in the hippocampus into adulthood in male AIE-exposed rats only. No significant AIE-induced differences were observed in the anti-inflammatory cytokines, IL-10 and TGF-β, nor in the neurotrophic factors BDNF and GDNF. Altogether, our findings indicate that although AIE did not have a persistent effect on hippocampal neurotrophic levels, there was still a reduction in neurogenesis. The neurogenic impairment was not sex specific, but the neurogenic deficits in males may be attributed to an increase in pro-inflammatory cytokine expression. A persistent impairment in neurogenesis may have an impact on both behavioral maladaptations and neurodegeneration in adulthood.

Associations between Adolescent Alcohol Use and Neurocognitive Functioning in Young Adulthood

This study examined the associations between excessive alcohol intake during adolescence and neurocognitive functioning in young adulthood and whether these relations varied by sex. Participants were working-class Chilean adolescents (N = 692; Mage 16.0 years; 54.5% female) who provided frequency of past 30-day bingeing and past-year intoxication. Neurocognitive measures were completed in young adulthood (Mage 21.2 years). Illicit substance users were excluded a priori and other substance use was controlled. When males and females were considered simultaneously, no main effects of intoxication or bingeing were found. However, several sex-specific effects emerged for intoxication, such that more frequent intoxication was associated with poorer visual memory, attention, processing speed, response inhibition, and cognitive flexibility in females, while frequent intoxication related to better attention and processing speed in males. In general, effect sizes were small. No relations emerged for verbal memory, working memory, or spatial learning. Possible factors that contribute to divergent sex effects are discussed.

Effects of binge drinking and the anti-inflammatory drug indomethacin on spatial memory and cognitive flexibility in mice

In previous research, we found that chronic-intermittent ethanol administration (CIEA), a model of binge drinking, impaired emotional memory in mice, and this impairment was counteracted by the anti-inflammatory drug indomethacin. In the present study, we evaluated the effects of CIEA on spatial memory and cognitive flexibility in adolescent mice of both sexes. Animals were randomly assigned to one of four groups for each sex: SS (saline + saline), SA (saline + alcohol), SI (saline + indomethacin), and AI (alcohol + indomethacin). They were injected with saline, ethanol (3 g/kg) or indomethacin (10 mg/kg) for the first three days of each week, throughout three weeks. 96 h after treatment, subjects learnt a standard water maze task on five consecutive days (4-day training and 1-day probe trial). One day later, mice underwent a reversal task for evaluating spatial cognitive flexibility. Animals receiving alcohol (SA and AI groups) did not differ from controls (SS groups) during the standard task, but animals treated with indomethacin performed better than controls, both in the acquisition trials and the probe trial. During the reversal task, no significant differences between alcohol groups and controls were observed, but the indomethacin group showed significant lower escape latencies than controls. No sex differences were found in either task. In conclusion, binge drinking does not impair spatial memory or spatial cognitive flexibility, while the anti-inflammatory indomethacin improves both, showing that the effects of alcohol and indomethacin on spatial memory (dependent on hippocampus) are different to those they exert on emotional memory (dependent on amygdala).

Primed for addiction: A critical review of the role of microglia in the neurodevelopmental consequences of adolescent alcohol drinking

Alcohol is one of the most widely used recreational substances worldwide, with drinking frequently initiated during adolescence. The developmental state of the adolescent brain makes it vulnerable to initiating alcohol use, often in high doses, and particularly susceptible to alcohol-induced brain changes. Microglia, the brain parenchymal macrophages, have been implicated in mediating some of these effects, though the role that these cells play in the progression from alcohol drinking to dependence remains unclear. Microglia are uniquely positioned to sense and respond to central nervous system insult, and are now understood to exhibit innate immune memory, or "priming," altering their future functional responses based on prior exposures. In alcohol use disorders (AUDs), the role of microglia is debated. Whereas microglial activation can be pathogenic, contributing to neuroinflammation, tissue damage, and behavioral changes, or protective, it can also engage protective functions, providing support and mediating the resolution of damage. Understanding the role of microglia in adolescent AUDs is complicated by the fact that microglia are thought to be involved in developmental processes such as synaptic refinement and myelination, which underlie the functional maturation of multiple brain systems in adolescence. Thus, the role microglia play in the impact of alcohol use in adolescence is likely multifaceted. Long-term sequelae may be due to a failure to recover from EtOH-induced tissue damage, altered neurodevelopmental trajectories, and/or persistent changes to microglial responsivity and function. Here, we review critically the literature surrounding the effects of alcohol on microglia in models of adolescent alcohol misuse. We attempt to disentangle what is known about microglia from other neuroimmune effectors, to which we apply recent discoveries on the role of microglia in development and plasticity. Considered altogether, these studies challenge assumptions that proinflammatory microglia drive addiction. Alcohol priming microglia and thereby perturbing their homeostatic roles in neurodevelopment, especially during critical periods of plasticity such as adolescence, may have more serious implications for the neuropathogenesis of AUDs in adolescents.

Nalmefene alleviates the neuroimmune response to repeated binge-like ethanol exposure: A TSPO PET imaging study in adolescent rats

A large body of preclinical research has shown that neuroimmunity plays a key role in the deleterious effects of alcohol (ethanol) to the brain. Translational imaging techniques are needed to monitor the efficacy of strategies to prevent or mitigate neuroinflammation and alleviate ethanol-induced neurotoxicity. Opioid receptor antagonists such as nalmefene are antagonists of the toll-like receptor 4, which may block the proinflammatory signaling cascade induced by ethanol at this specific target. Male adolescent rats received a validated protocol of ethanol injection (i.p, 3 g/kg daily for two consecutive days followed by two resting days) during 14 days. Positron emission tomography (PET) imaging with the translocator protein 18 kDa (TSPO) radioligand [¹⁸ F]DPA-714 was performed at day-15. Toxicity induced by repeated binge-like ethanol exposure (71% mortality) was drastically reduced by nalmefene pretreatment (0.4 mg/kg, 14% mortality). No mortality was observed in animals that received vehicle (control) or nalmefene alone. Compared with control animals (n = 10), a significant 2.8-fold to 4.6-fold increase in the volume of distribution (V_T ) of [¹⁸ F]DPA-714 was observed among brain regions in animals exposed to ethanol only (n = 9). Pretreatment with nalmefene significantly alleviated the neuroimmune response to ethanol exposure in all brain regions (1.2-fold to 2.5-fold increase in V_T ; n = 5). Nalmefene alone (n = 6) did not impact [¹⁸ F]DPA-714 V_T compared with the control group. Nalmefene may protect against the neuroinflammatory response and overall toxicity associated with binge drinking. [¹⁸ F]DPA-714 PET imaging can be used to noninvasively address the neuroimmune impact of ethanol exposure and its modulation by pharmacological strategies in vivo, with translational perspectives.

The Effects of Light-to-Moderate Alcohol Consumption on the Cognitive Function of Community Nondemented Male Elderly: A Cohort Study

Aim

To investigate the effects of light-to-moderate drinking on the cognitive function of the elderly in a large elderly community cohort. Although heavy drinking is linked with impaired brain functions, the effects of light-to-moderate drinking on the cognitive function of the elderly are still controversial.

Methods

A total of 1469 nondemented elderly men from 15 research centers in 8 cities and provinces were included and divided into two groups: drinking (531 subjects) and nondrinking (938 subjects). Cognitive functions were assessed by the Beijing version of the Montreal Cognitive Assessment (MoCA) at baseline and one-year follow-up.

Results

There was no difference in total cognitive scores between the light-to-moderate drinking and nondrinking groups at baseline and follow-up. Nonalcohol users performed better naming and abstraction function at baseline and better naming function at follow-up. There was no difference in cognitive performance decline and new-onset dementia rates at follow-up.

Conclusions

Light-to-moderate alcohol consumption had no significant impact on the overall cognitive function and the risk of dementia in elderly men.

Binge Drinking, Alone or With Cannabis, During Adolescence Triggers Different Effects on Immediate Visual Memory in Men and Women

Background: This study examines the interaction between a history of binge drinking (BD), alone or with cannabis consumption, and the effects of acute alcohol exposure on immediate visual memory (IVM) (faces memory task, scenes memory task and IVM-IQ) in adolescents of both sexes. Method: Two hundred and ninety adolescents, grouped into refrainers, binge drinkers and subjects with a history of simultaneous BD/Cannabis co-use, received a risk dose of alcohol or a control drink. Results: Consumption Pattern (refrainers vs. binge drinkers vs. BD/Cannabis consumers) was not significant, while Treatment (acute alcohol vs. control drink) was significant in both sexes. Also, male binge drinkers' performance in the faces memory task was poorer than that of refrainers and BD/Cannabis consumers who consumed the control drink. BD/Cannabis consumers performed this task as capably as refrainers. In women, binge drinkers performed better than refrainers in scene memory and IVM-IQ tests when given alcohol, and binge drinkers performed worse than refrainers after consuming the control drink. Conclusions: Acute alcohol consumption worsens IVM. Cannabis exerts a buffering effect in men. A cognitive tolerance effect is observed in women. Exposure during adolescence to alcohol, alone or with cannabis, can trigger different cognitive effects in men and women that could endure into adulthood.

Emotional memory impairment produced by binge drinking in mice is counteracted by the anti-inflammatory indomethacin

The Binge Drinking (BD) pattern of alcohol consumption, prevalent in adolescents and young adults, has been associated with memory impairment. In addition, evidence shows that alcohol abuse causes neuroinflammation, which may contribute to the brain damage produced by alcohol and explain its cognitive consequences. In this study, we evaluated the effectiveness of the anti-inflammatory indomethacin in counteracting the memory impairment produced by alcohol (ethanol) in adolescent mice of both sexes. Animals were randomly assigned to one of four groups for each sex: SS (saline + saline), SA (saline + alcohol), SI (saline + indomethacin) and AI (alcohol + indomethacin). They were injected acutely (Experiment 1) or chronically intermittent (Experiment 2) with saline, ethanol (3 g/kg) and indomethacin (10 mg/kg). All subjects were evaluated in an inhibitory avoidance task 96 h after treatment. With acute administration, SA groups showed significantly lower Test latencies than SS groups, while AI groups had similar latencies to controls. The chronic-intermittent administration of alcohol, an animal model of BD, produced significant emotional memory impairment -blocking learning in males- which was counteracted by indomethacin, as the AI groups had similar latencies to the SS groups. No significant differences were observed in locomotor activity or analgesia. In conclusion, alcohol BD (one or several episodes) impairs emotional memory in mice. This impairment is not secondary to the effects of alcohol BD on locomotor activity or pain sensitivity, and it is counteracted by indomethacin. Therefore, the memory impairment produced by alcohol BD seems to be mediated, in part, by neuroinflammatory processes. These findings open a window for new treatments for alcohol use disorders.

Neurobiological and Cognitive Profile of Young Binge Drinkers: a Systematic Review and Meta-Analysis

This review provides the first systematic and quantitative synthesis of the literature examining the relationship between binge drinking, cognition, brain structure and function in youth aged 10 to 24 years. PubMed, EMBASE, Medline, PsychINFO and ProQuest were searched for neuroimaging, neurophysiological, and neuropsychological studies. A total of 58 studies (21 neuroimaging, 16 neurophysiological, 21 neuropsychological) met the eligibility criteria and were included in the review. Overall, abnormal or delayed development of key frontal executive-control regions may predispose youth to binge drink. These abnormalities appear to be further exacerbated by the uptake of binge drinking, in addition to alcohol-related neural aberrations in reward-seeking and incentive salience regions, indexed by cognitive deficits and maladaptive alcohol associations. A meta-analysis of neuropsychological correlates identified that binge drinking in youth was associated with a small overall neurocognitive deficit (g = -0.26) and specific deficits in decision-making (g = -1.70), and inhibition (g = -0.39). Using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) Evidence Profile, the certainty in outcomes ranged from very low to low. Future prospective longitudinal studies should address concomitant factors, exposure thresholds, and age-related vulnerabilities of binge drinking, as well as the degree of recovery following discontinuation of use.

Alcohol Consumption and Subclinical Findings on Cognitive Function, Biochemical Indexes, and Cortical Anatomy in Cognitively Normal Aging Han Chinese Population

Background: Binge drinking of alcohol is associated with brain damage, but less is known about relationship of light-to-moderate alcohol consumption with cognitive function, biochemical indexes, and cortical anatomy. Previous findings have debated on whether light-to-moderate drinking has any health benefits. We investigated cortical thickness and its association with alcohol consumption and cognitive functions in a non-dementia aging Han Chinese population.

Methods: 940 non-dementia aging subjects were included in our study (alcohol n = 149; non-alcohol n = 791). Among them, 572 received blood biochemical tests including liver function and lipid metabolism (alcohol n = 100; non-alcohol n = 472) and 141 had brain magnetic resonance imaging (alcohol n = 27; non-alcohol n = 114). The Beijing version of the Montreal Cognitive Assessment and the Chinese version of the neuropsychological test battery were used to assess cognitive functions.

Results: There was no significant difference in cognitive functions between alcohol and non-alcohol groups in the overall database. Similarly, there was no significant difference in liver function and lipid metabolism between two groups in the sub-database. The left superiortemporal gyrus was one of age sensitive regions and alcohol consumption was significantly associated with thinner cortex of the left superiotemporal cluster in the sub-database.

Conclusion: Alcohol consumption was not significantly associated with better or worse cognitive function and biochemical indexes abnormality, however, significantly associated with thinner cortex of the left superiortemporal gyrus in cognitively normal aging Han Chinese population.

Binge Drinking and the Young Brain: A Mini Review of the Neurobiological Underpinnings of Alcohol-Induced Blackout

Binge drinking has significant effects on memory, particularly with regards to the transfer of information to long-term storage. Partial or complete blocking of memory formation is known as blackout. Youth represents a critical period in brain development that is particularly vulnerable to alcohol misuse. Animal models show that the adolescent brain is more vulnerable to the acute and chronic effects of alcohol compared with the adult brain. This mini-review addresses the neurobiological underpinnings of binge drinking and associated memory loss (blackout) in the adolescent and young adult period. Although the extent to which there are pre-existing versus alcohol-induced neurobiological changes remains unclear, it is likely that repetitive binge drinking in youth has detrimental effects on cognitive and social functioning. Given its role in learning and memory, the hippocampus is a critical region with neuroimaging research showing notable changes in this structure associated with alcohol misuse in young people. There is a great need for earlier identification of biological markers associated with alcohol-related brain damage. As a means to assess in vivo neurochemistry, magnetic resonance spectroscopy (MRS) has emerged as a particularly promising technique since changes in neurometabolites often precede gross structural changes. Thus, the current paper addresses how MRS biomarkers of neurotransmission (glutamate, GABA) and oxidative stress (indexed by depleted glutathione) in the hippocampal region of young binge drinkers may underlie propensity for blackouts and other memory impairments. MRS biomarkers may have particular utility in determining the acute versus longer-term effects of binge drinking in young people.