Impulsivity as a Multifaceted Construct Related to Excessive Drinking Among UK Students

The role of impulsivity in the relationship between affect and alcohol consumption in young adults

BACKGROUND

Theoretical models of alcohol use posit that individuals consume alcohol to ameliorate negative affect or to heighten positive affect. It is important, however, to consider the influence of factors that may determine an individual's tendency to consume excessive amounts of alcohol under positive and negative circumstances. Thus, the current study examined a large sample of young adults to clarify whether positive and negative affect predict total alcohol consumption on drinking days and whether facets of impulsivity moderate these relationships.

METHODS

Six-hundred ninety-three young adults (Mage  = 19.71 years, SD = 2.04; female = 62.9%) completed the Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scales at baseline followed by daily measures of positive and negative affect and self-reported alcohol use for 13 days. Generalized linear mixed models were specified to assess the role of pre-consumption affect on total drinks consumed across drinking days and to determine the moderating effect of each BIS/BAS subscale.

RESULTS

Participants were significantly more likely to drink in greater quantities on occasions preceded by higher positive affect but not negative affect. While fun-seeking positively predicted total drinks consumed, there were no significant interaction effects between the BIS/BAS subscales and affect on total drinks consumed.

CONCLUSIONS

These findings challenge existing affect regulation models and have implications for ecological momentary interventions aimed at addressing hazardous drinking behaviors.

Sex differences in associations between delay discounting and expectancies for alcohol analgesia

Self-medication of pain with alcohol is prevalent, and expectancies for alcohol analgesia likely influence pain relief and alcohol consumption. Hazardous alcohol use has been associated with greater delay discounting rates; however, little is known about the relationship between delay discounting and expectancies for alcohol analgesia. Therefore, the present study examined sex differences in associations between delay discounting and expectancies for alcohol analgesia. Healthy drinkers without chronic pain (N = 53) completed measures of expectancies for alcohol analgesia, alcohol use, and alcohol outcome expectancies. A five-trial adjusting-delay discounting task (DDT) for monetary outcomes was also administered. Regression analyses revealed that sex moderated the relationship between delay discounting and expectancies for alcohol analgesia. Steeper delay discounting rates were associated with weaker expectancies for alcohol analgesia among men when adjusting for average alcohol consumption. Among women, nonsignificant associations between delay discounting rates and expectancies for alcohol analgesia were observed. These findings provide initial evidence of sex differences in associations between delay discounting and expectancies for alcohol analgesia. The directionality of these associations was unexpected and may have implications for patterns of self-medication with alcohol. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Testing the validity and reliability of the Matching Familiar Figures Test-2021: An updated behavioral measure of reflection–impulsivity

The Matching Familiar Figures Test (MFFT) is a well-known and extensively used behavioral measure of reflection-impulsivity. However, the instrument has several deficiencies, including images designed for school-age children in the United States during the 1960s. Most importantly, an adult version of the instrument is currently unavailable and the lack of a single repository for the images raises questions regarding the MFFT’s validity and reliability. We developed a 21st century version of the MFFT using images that are familiar to adults and reside in a freely accessible repository. We conducted two studies examining validity and reliability issues. In Study 1, participants interacting with the MFFT-2021, versus those interacting with the original MFFT20, spent more time on the task, took more time in making their first response, and were more likely to complete the task without errors, even though the average number of errors was higher than the comparison group. The coherence of these results is evidence of convergent validity. Regarding predictive validity, the MFFT-2021 remained a reliable predictor of rational thinking, such that participants who demonstrated more reflection (less impulsivity) tended to avoid rational thinking errors. Also, performance on the MFFT-2021 predicted higher quality judgments in processing job characteristic cues with embedded interactions, a form of configural information processing. We also found evidence of concurrent validity: performance on the MFFT-2021 differed in a predictable manner for participants grouped by their performance on the Cognitive Reflection Test. In Study 2, we tested discriminant validity by comparing participant performance on the MFFT-2021 to their performance on the Information Sampling Task (IST), another behavioral measure of reflection-impulsivity used in studies of psychopharmacological and addiction behaviors. For our participants (undergraduate business students), we found that the MFFT was a stronger predictor of performance on rational thinking tasks, and, contrary to prior studies, our exploratory factor analysis identified separate factors for the MFFT-2021 and the IST, supporting discriminant validity, indicating that these two instruments measure different subtypes of reflection-impulsivity.

The use of transcranial direct current stimulation (tDCS) to reduce impulsivity and aggression in adults with mild intellectual developmental disabilities: the tDCS-RIADD randomised controlled trial protocol

Background

Challenging behaviours, in particular aggressive behaviours, are prevalent among people with intellectual developmental disabilities. Predictors of challenging behaviours are numerous, including past history of aggression, poor coping skills and impulsivity. Factors like motor or rapid-response impulsivity (RRI) have neurobiological underpinnings that may be amenable to change via neuromodulation using non-invasive brain stimulation techniques like transcranial direct current stimulation (tDCS).

Methods

This study aims to determine the efficacy of anodal tDCS in reducing RRI and incidents of aggression in people with intellectual developmental disabilities (IDD) in residential or hospital settings. Using a single blind, randomised, sham-controlled trial design, adults with IDD, with a history of impulsivity leading to aggression, will be randomised to receive either repetitive anodal or sham tDCS applied to the left dorsolateral prefrontal cortex. Outcome measures assessing impulsivity and aggression will be collected for up to 1 month following the last tDCS session.

Discussion

The results of this study may pave the way for developing targeted interventions for impulsivity and aggressive behaviours in people with IDD.

Addressing methodological issues in a study of impulsivity and vulnerability for transition to alcohol use disorder

BACKGROUND

Heightened behavioral impulsivity has been advocated as a preexisting risk factor for the development of alcohol use disorder (AUD). Nonetheless, studies investigating impulsivity in adolescent/young adult at-risk drinkers-who are at increased risk of developing AUD-report mixed findings. This may be due to methodological limitations related to definitions of at-risk drinking, the retrospective assessment of alcohol intake, and/or the relatively modest sample size of some studies.

METHODS

Healthy individuals (N = 814, M_age  = 22.50) completed online surveys and a measure of choice impulsivity. Of these, a number of participants also undertook an online measure of response inhibition (n = 627, M_age  = 22.66), and a further subgroup submitted real-time alcohol consumption information for a period of 21 days using an app (n = 543, M_age  = 22.96). Differences in behavioral impulsivity were assessed as a function of various at-risk alcohol intake categories. Hierarchical multiple regression was employed to determine whether impulsivity predicted alcohol use in the form of a continuous index comprising variables related to intake and consequences of use.

RESULTS

Significantly greater impulsivity was not evident in heavy, standard binge, high binge, harmful, or hazardous alcohol drinkers as compared to controls, regardless of the criteria employed to categorize these at-risk drinkers. Neither choice impulsivity nor reduced response inhibition significantly predicted the alcohol use index.

CONCLUSIONS

While results could be attributed to the online nature of this research, it is possible that more sensitive measures of behavioral impulsivity are required when assessing nondependent drinkers.

Mind training, stress and behaviour-A randomised experiment

In this paper, we evaluate the effects of a psychological training, called Mindfulness-Based Stress Reduction (MBSR) on stress and risk and time preferences. MBSR is a well-known psychological technique, which is believed to improve self-control and reduce stress. We conduct the experiment with 139 participants, half of whom receive the MBSR training, while the other half are asked to watch a documentary series, both over 4 consecutive weeks. Using a range of self-reported and physiological measures (such as cortisol measures), we find evidence that mindfulness training reduces perceived stress, but we only find weak evidence of effects on risk and inter-temporal attitudes.

Impulsivity Scale-12 and its utilization in alcohol use disorder

INTRODUCTION

One of the core symptoms of alcohol use disorder (AUD) is impulsivity. The recently published study on the Impulsivity Scale 12 (IS-12) offers a promising tool to use in clinics working with clients with AUD due to its simplicity. IS-12 includes subscales related tocognitive impulsivity and behavioral impulsivity, which are related to different aspects of AUD symptomatology. The aim of the study was to adapt IS-12 to polish and test its utility in a sample of patients diagnosed with AUD.

METHODS

Using a Confirmatory Factor Analysis, we compared the two-factor model of the Polish adaptation of the BIS-11 and the IS-12 on a sample of 615 patients diagnosed with AUD. Additionally, we explored the association between the IS-12's cognitive impulsivity and behavioral impulsivity subscales and depressive symptoms, AUD severity, and suicidal ideation using Structural Equation Modeling on a subsample of 450 patients with AUD.

RESULTS

The IS-12 demonstrated a better model fit and good reliability compared to the BIS-11. Moreover, cognitive impulsivity predicted suicidal ideation, but not AUD severity, while behavioral impulsivity predicted AUD severity, but not suicidal ideation. Both subscales of IS-12 predicted depressive symptoms.

CONCLUSION

Consistent with prior work, findings indicate that the second-order factor model of the BIS-11 had reliability issues and evidenced poor model fit. In contrast, the IS-12 demonstrated a satisfactory model fit and was predictive of clinical symptomatology. Thus, utilizing an easy tool, such as IS-12, might be beneficial for researchers and clinicians working with patients with AUD.

Limited Evidence of Associations Between Executive Functioning and Alcohol Involvement In UK Adolescents

Aims

Deficits in motor inhibitory control and working memory have been hypothesized to be both a cause and consequence of heavy alcohol use. Adolescence is a critical developmental stage for inhibitory control and working memory, and it is also a stage when individuals are most likely to initiate alcohol use. This study aimed to examine whether inhibitory control and working memory would predict alcohol use and involvement in a group of UK adolescents.

Methods

We recruited 220 (N = 178, female) adolescents, aged between 16 and 18, from eight higher education settings in the Merseyside region of the UK. Alcohol use was examined using the Timeline Follow-Back and involvement (and related problems) using the Adolescent Alcohol Involvement Scale. A reward-based inhibitory control task (Go/No-Go) was used to examine the inhibition and reward sensitivity, and a self-ordered pointing task was used to measure working memory.

Results

Multiple regression demonstrated that neither inhibitory control (b = 0.02 (95% confidence interval (CI): −0.21, 0.24)) nor working memory (b = −0.12 (95% CI: −0.30, 0.07)) were significant predictors of alcohol use (units consumed). Inhibitory control (b = 0.61 (95% CI: 0.12, 1.09), specifically, in the no reward condition and school deprivation (b = 0.67 (95% CI: 0.06, 1.28) significantly predicted alcohol-related problems.

Conclusions

Our findings demonstrated limited evidence that deficits in specific mechanisms of executive functioning (i.e. motor inhibition and working memory) were associated with alcohol-related problems in UK adolescents. This study adds to an increasing body of literature suggesting weak or non-existent links between inhibitory control, working memory and alcohol use.

Deter the emotions: Alexithymia, impulsivity and their relationship to binge drinking

Introduction

The relevance of both emotion processing and impulsivity to alcohol use and misuse is increasingly recognised, yet there is a scarcity of studies addressing their reciprocal interaction. The present study aimed to examine the role that difficulties in emotion processing and trait impulsivity play in explaining binge drinking pattern of alcohol use in student population. We looked at binge drinking, as it is a risk factor to later alcohol abuse and is a common alcohol drinking habit among students. Alexithymia (from Greek as "deter/repel emotions"), a difficulty in identifying and describing feelings in self and others is increasingly recognised as a feature of alcohol misuse.

Methods

One-hundred and seventy-four student alcohol drinkers were assessed for their drinking habits (Alcohol Use Questionnaire), as well as for alexithymia (Toronto Alexithymia Scale) and impulsivity trait (Barratt Impulsiveness Scale); facial emotional expression judgements were also tested.

Results

A direct relationships between, both, alexithymia and impulsivity, and binge drinking was found. When combined, trait impulsivity partially mediated the relationship between alexithymia and binge drinking. Facial emotional expression judgements also showed a relationship with binge drinking.

Conclusions

These findings highlight the importance of both emotion processing and impulsivity in understanding binge drinking and indicate potential routes for prevention and intervention techniques, especially towards those who may be at risk of later alcohol abuse.

Relevance of routine activities for understanding the impact of the dual systems model on binge drinking among college students

BACKGROUND

Past research has indicated that dual systems model constructs (impulsivity, sensation-seeking) are predictors of binge drinking. Further, engagement in routine unstructured social activities also predicts elevated risk for binge drinking. However, there has yet to be any research that examines the interactive effect of these constructs.

METHODS

The present study utilized a sample of 248 undergraduate students to understand the relationships between concepts on interest. A series of ordinal logistic regression models were estimated to determine the direct effects of impulsivity, sensation-seeking, and routine activities on binge drinking and also determine whether or not involvement in routine activities moderated the direct effects of either impulsivity and/or sensation-seeking on binge drinking.

RESULTS

Results indicated that lower sensation-seeking was associated with elevated binge drinking frequency. However, the interaction between routine activities and sensation-seeking indicated a positive relationship. This meant that the effects of high levels of sensation-seeking on binge drinking were exacerbated at higher levels of routine activities involvement.

CONCLUSIONS

Findings of the present study indicate that students high in sensation-seeking and engagement in unstructured socializing present great risk for high frequency binge drinking. However, students who demonstrate low levels of sensation-seeking may also present an at-risk population, as they may be using alcohol to self-medicate anhedonia symptoms.

The impact of health literacy on college students' psychological disturbances and quality of life: a structural equation modeling analysis

Background

The literature regarding the effect of health literacy on college students’ psychological health and quality of life is scarce. The purpose of conducting this cross-sectional study was to examine the effect of health literacy on certain psychological disturbances (perceived stress, depressive symptoms, and impulsivity) and quality of life of college students.

Methods

A cross-sectional quantitative design was utilized in this study. A total of 310 four-year college students participated in this study. The students completed a demographics questionnaire as well as already established and validated measures of health literacy, perceived stress, depressive symptoms, impulsivity, and quality of life. Structural equation modeling was performed to analyze the data to explore the effect of health literacy on the psychological disturbances and quality of life.

Results

The results showed that health literacy has a negative effect on three psychological disturbances commonly experienced by college students; perceived stress, depressive symptoms, and impulsivity. In addition, the effect of health literacy on the quality of life was positive.

Conclusion

The proposed conceptual model was supported. College students’ counseling staff could use the findings to better address students’ needs pertinent to psychological health and quality of life. Future research is warranted to develop a more comprehensive model that explains the role of health literacy in determining college students’ psychological health and quality of life.

Differential brain responses for perception of pain during empathic response in binge drinkers compared to non-binge drinkers

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We measure empathic responses to imagery pain while adopting a ‘self’ vs ‘other’ perspective.

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Social drinkers who binge drink respond more slowly to imagery pain than those who do not.

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Binge drinkers show also stronger activation in fusiform body area to imagery pain ‘other’

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Differences between binge and non-binge drinkers relate to ‘self’ vs. ‘other’ distinction.

Individuals who engage in binge drinking behaviors may show evidence of impaired cognitive function and emotional dysregulation. Impaired empathy, characterized by a reduced ability to understand and respond appropriately to feelings of others, is increasingly recognized for its role in Alcohol Use Disorders (AUD). The present study examined a population of young adult social drinkers to compare individuals who show binge drinking behavior to those who do not on measures of empathic processing and associated neural responses. A secondary aim explored similarities and differences between binge drinkers living in the UK and France. Alcohol drinking history and impulsivity ratings were recorded from seventy-one participants [(37 UK (Binge drinkers N = 19); 34 France (Binge drinkers N = 17)], who then underwent a neuroimaging study. During functional magnetic resonance imaging, participants viewed images of bodily pain (vs. no-pain), while adopting the perspective of self (pain recipient) or other (observer of someone else experiencing pain). Anterior midcingulate cortex (aMCC) and insula activation distinguished pain from no-pain conditions. Binge drinkers showed stronger regional neural activation than non-binge drinkers within a cluster spanning fusiform gyrus and inferior temporal gyrus, encompassing the Fusiform Body Area. Binge drinkers compared to non-binge drinkers also took longer to respond when viewing pictures depicting pain, in particular when adopting the perspective of self. Relationships between changes in brain activation and behavioural responses in pain versus no pain conditions (self or other perspective) indicated that whereas non-binge drinkers engage areas supporting self to other distinction, binge drinkers do not. Our findings suggest that alcohol binge drinking is associated with different empathy-related behavioral and brain responses, consistent with the proposed importance of empathy in the development of AUD.

Are hazardous drinkers more impulsive than light drinkers? A comprehensive assessment in young adults

Those with alcohol dependence are characteristically impulsive. It is unclear whether the same is true of hazardous drinkers (i.e., women routinely drinking more than 14 units in a typical week but fewer than 35, and men drinking more than 14 units but fewer than 50). Yet, it is important to understand the mechanisms involved in such drinking, since it places the drinker at risk for future harm. The present study thus comprehensively assessed whether impulsivity was elevated in hazardous drinkers, compared to lighter drinkers. An opportunity sample of 57 light and 49 hazardous drinkers was assessed on the following impulsivity subdomains (via the measures in parentheses): (i) trait impulsivity (the Barratt Impulsiveness Scale, Version 11); (ii) temporal impulsivity (the Monetary Choice Questionnaire); (iii) stopping impulsivity (the Stop-Signal Task); (iv) waiting impulsivity (the Continuous Performance Task or CPT); (v) reward-sensitivity (the Behavioural Activation Scales); and (vi) risk-taking (the Balloon Analogue Risk Task). Alcohol- and other drug-dependent individuals were excluded from the study, while socio-demographics (age, gender, and socio-economic status), mood, binge drinking, and nicotine intake were all controlled for. The groups were compared via a series of Bonferroni-corrected, independent-measures t tests. The results revealed that hazardous drinkers were more impulsive than light drinkers on the CPT; there were no other statistically significant group differences. Consistent with the above, a logistic regression, with drinking group as the dependent variable and the impulsivity indices as independent variables, revealed that only CPT performance was a significant predictor of drinking status. Other than gender, none of the control variables significantly correlated with CPT performance. A sequential linear regression revealed that drinking status continued to predict CPT performance, after first accounting for gender. Thus, from a battery of impulsivity measures, only waiting impulsivity (i.e., CPT score) was elevated in hazardous drinkers, relative to lighter drinkers. Waiting impulsivity may thus be important in the maintenance of hazardous drinking.

Disentangling the Relationship Between Self-Esteem and Problematic Alcohol Use Among College Students: Evidence From a Cluster Analytic Approach

AIMS

Investigation of the relationship between self-esteem and alcohol use among college students has yielded discrepant results. We hypothesized that these discrepancies could originate from a potential heterogeneity of self-esteem patterns among young adult with an alcohol use disorder (AUD).

METHODS

A community sample of 343 college students was recruited and categorized with or without AUD using the Alcohol Use Disorders Identification Test cut-offs. College students were compared on the dimensions of the Coopersmith Self-Esteem Inventory (CSEI) as well as mood, impulsiveness, alcohol- and other substance-related measures, including drinking motives.

RESULTS

A cluster analysis conducted among college students with AUD highlighted two subgroups characterized by contrasting patterns on the CSEI: one group with a high level of self-esteem and low levels of anxiety and depression symptoms and one group with a low level of self-esteem and high levels of impulsiveness, mood symptoms and drinking to cope motives.

CONCLUSION

Findings caution against assuming that AUD is associated with low self-esteem, as reported in previous studies. These results rather emphasize a heterogeneity of self-esteem in college students, showing that high self-esteem was also related to AUD. Implications of these results are major for prevention purposes and clinical practice.

Inhibitory-control event-related potentials correlate with individual differences in alcohol use

Impulsivity is a multidimensional construct that is related to different aspects of alcohol use, abuse, and dependence. Inhibitory control, one facet of impulsivity, can be assayed using the stop-signal task (SST) and quantified behaviorally via the stop-signal reaction time (SSRT) and electrophysiologically using event-related potentials (ERPs). Research on the relationship between alcohol use and SSRTs, and between alcohol use and inhibitory-control ERPs, is mixed. Here, adult alcohol users (n = 79), with a wide range of scores on the Alcohol Use Disorders Identification Test (AUDIT), completed the SST under electroencephalography (EEG) (70% of participants had AUDIT total scores greater than or equal to 8). Other measures, including demographic, self-report, and task-based measures of impulsivity, personality, and psychological factors, were also recorded. A machine-learning method with penalized linear regression was used to correlate individual differences in alcohol use with impulsivity measures. Four separate models were tested, with out-of-sample validation used to quantify performance. ERPs alone statistically predicted alcohol use (cross-validated r = 0.28), with both early and late ERP components contributing to the model (larger N2, but smaller P3, amplitude). Behavioral data from a wide range of impulsivity measures were also associated with alcohol use (r = 0.37). SSRT was a relatively weak statistical predictor, whereas the Stroop interference effect was relatively strong. The addition of nonimpulsivity behavioral measures did not improve the correlation (r = 0.34) and was similar when ERPs were combined with non-ERP data (r = 0.29). These findings show that inhibitory control ERPs are robustly correlated individual differences in alcohol use.

The relation between ADHD symptoms, perceived stress and binge drinking in college students

Binge drinking is a major public health problem associated with various negative short-term and long-term clinical and social outcomes. If there is evidence to suggest a relationship between ADHD and alcohol use in college students, no study has investigated the role of ADHD symptomatology in binge drinking. Thus, this research was designed to explore the relative contributions of inattention and hyperactivity/impulsivity symptoms to binge drinking in a sample of French college students while controlling for effects of perceived stress. Participants (N = 7011; mean age = 20.9; 74.9% of females) completed self-report surveys assessing ADHD symptoms, perceived stress, sociodemographic characteristics, and binge drinking frequency. Multinomial logistic regression revealed significant associations between higher levels of ADHD symptoms in general, but not perceived stress, and increasing frequency of binge drinking. Moreover, higher levels of inattention and hyperactivity/impulsivity symptoms were independently associated with greater frequency of binge drinking. The association was stronger between high rates of binge drinking and inattention than for hyperactivity/impulsivity. These findings, which remained statistically significant after adjusting for a range of potential confounders (including perceived stress), suggest that the presence of ADHD symptoms may be an important factor related to binge drinking.

The Role of Impulsivity Facets on the Incidence and Development of Alcohol Use Disorders

Alcohol Use Disorder (AUD) is a chronic relapsing disorder defined according to the Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5; American Psychiatric Association 2013), "by a cluster of behavioural and physical symptoms, which can include, withdrawal, tolerance and craving". Social, emotional, behavioural and cognitive factors are important contributors to AUD. Impulsivity, a multifaceted behavioural concept, defined as a predisposition for rapid and unplanned actions, without considering potential negative consequences of these actions, represents an important such factor. In this chapter, research on the role of distinct impulsivity dimensions in different severity stages of alcohol use is presented.Increased self-reported (trait) impulsivity and an inability to wait, as well as difficulty to adjust behaviour appropriately following a failure to withhold a response are observed across the spectrum of alcohol-use severities. Research on temporal impulsivity (inability to delay gratification) consistently shows deficits in more severe alcohol users. Data on temporal impulsivity in early stages of alcohol use are less consistent, with some studies showing no differences between high and moderate drinkers, while others indicating increased impulsivity in high alcohol users. Data on reflexion impulsivity are currently limited to draw conclusions. Recent research is also presented suggesting the importance of perception and interpretation of physiological and emotional signals on alcohol use behaviour highlighting the necessity of comprehensive integration of the field of the study of emotion and interoception with impulsivity research.

GABAAR α2-activated neuroimmune signal controls binge drinking and impulsivity through regulation of the CCL2/CX3CL1 balance

BACKGROUND AND PURPOSE

Toll-like receptors (TLRs) are a family of innate immune system receptors that respond to pathogen-derived and tissue damage-related ligands and are increasingly recognized for their impact on homeostasis and its dysregulation in the nervous system. TLR signaling participates in brain injury and addiction, but its role in the alcohol-seeking behavior, which initiates alcohol drinking, is still poorly understood. In this review, we discuss our findings designed to elucidate the potential contribution of the activated TLR4 signal located in neurons, on impulsivity and the predisposition to initiate alcohol drinking (binge drinking).

RESULTS

Our findings indicate that the TLR4 signal is innately activated in neurons from alcohol-preferring subjects, identifying a genetic contribution to the regulation of impulsivity and the alcohol-seeking propensity. Signal activation is through the non-canonical, previously unknown, binding of TLR4 to the α2 subunit of the γ-aminobutyric 2 acid A receptor (GABAAR α2). Activation is sustained by the stress hormone corticotrophin-releasing factor (CRF) and additional still poorly recognized ligand/scaffold proteins. Focus is on the effect of TLR4 signal activation on the balance between pro- and anti-inflammatory chemokines [chemokine (C-C motif) ligand 2 (CCL2)/chemokine (C-X3-C motif) ligand 1 (CX3CL1)] and its effect on binge drinking.

CONCLUSION

The results are discussed within the context of current findings on the distinct activation and functions of TLR signals located in neurons, as opposed to immune cells. They indicate that the balance between pro- and anti-inflammatory TLR4 signaling plays a major role in binge drinking. These findings have major impact on future basic and translational research, including the development of potential therapeutic and preventative strategies.

The Mediating Role of Impulsivity Between Psychological Distress and Alcohol Misuse Among College Students at a Historically Black University

Objective: Alcohol misuse is prevalent and clinically significant among college students. Psychological distress is one factor that has been found to predict alcohol misuse in this population. However, relatively few investigations examined the association of psychological distress to alcohol misuse or its underlying mechanisms among students attending historically Black colleges and universities (HBCUs). The present study examined whether impulsivity explains the relation between psychological distress and alcohol misuse in this population using structural equation modeling. Methods: Participants were 287 undergraduate students attending an HBCU in the southern United States (M_age = 22.5, 66.3% female, 93.7% Black). Results: Impulsivity was found to significantly mediate the association of psychological distress to alcohol misuse, such that higher levels of psychological distress were associated with greater impulsivity which, in turn, was related to more alcohol misuse. Further analyses indicated that attentional impulsivity significantly mediated the association of psychological distress to alcohol misuse. Conclusions: These findings suggest the utility of targeting impulsivity in interventions aimed at preventing and reducing alcohol misuse among college students attending HBCUs who experience psychological distress.

Genome-Wide Association Studies of Impulsive Personality Traits (BIS-11 and UPPS-P) and Drug Experimentation in up to 22,861 Adult Research Participants Identify Loci in the CACNA1I and CADM2 genes

Impulsive personality traits are complex heritable traits that are governed by frontal-subcortical circuits and are associated with numerous neuropsychiatric disorders, particularly drug abuse and attention-deficit/hyperactivity disorder (ADHD). In collaboration with the genetics company 23andMe, we performed 10 genome-wide association studies on measures of impulsive personality traits [the short version of the UPPS-P Impulsive Behavior Scale, and the Barratt Impulsiveness Scale (BIS-11)] and drug experimentation (the number of drug classes an individual had tried in their lifetime) in up to 22,861 male and female adult human research participants of European ancestry. Impulsive personality traits and drug experimentation showed single nucleotide polymorphism heritabilities that ranged from 5 to 11%. Genetic variants in the CADM2 locus were significantly associated with UPPS-P Sensation Seeking (p = 8.3 × 10^-9, rs139528938) and showed a suggestive association with Drug Experimentation (p = 3.0 × 10^-7, rs2163971; r ² = 0.68 with rs139528938). Furthermore, genetic variants in the CACNA1I locus were significantly associated with UPPS-P Negative Urgency (p = 3.8 × 10^-8; rs199694726). The role of these genes was supported by single variant, gene- and transcriptome-based analyses. Multiple subscales from both UPPS-P and BIS showed strong genetic correlations (>0.5) with Drug Experimentation and other substance use traits measured in independent cohorts, including smoking initiation, and lifetime cannabis use. Several UPPS-P and BIS subscales were genetically correlated with ADHD (r _g = 0.30-0.51), supporting their validity as endophenotypes. Our findings demonstrate a role for common genetic contributions to individual differences in impulsivity. Furthermore, our study is the first to provide a genetic dissection of the relationship between different types of impulsive personality traits and various psychiatric disorders.SIGNIFICANCE STATEMENT Impulsive personality traits (IPTs) are heritable traits that are governed by frontal-subcortical circuits and are associated with neuropsychiatric disorders, particularly substance use disorders. We have performed genome-wide association studies of IPTs to identify regions and genes that account for this heritable variation. IPTs and drug experimentation were modestly heritable (5-11%). We identified an association between single nucleotide polymorphisms in CADM2 and both sensation seeking and drug experimentation; and between variants in CACNA1I and negative urgency. The role of these genes was supported by single variant, gene- and transcriptome-based analyses. This study provides evidence that impulsivity can be genetically separated into distinct components. We showed that IPT are genetically associated with substance use and ADHD, suggesting impulsivity is an endophenotype contributing to these psychiatric conditions.

Earlier Alcohol Use and Lower Neuropsychological Performance in Brazilian Adolescence: Is the School Environment Related to This?

OBJECTIVES

The aim of this study was to evaluate impulsivity, inhibitory control, and alcohol use in preadolescents and adolescents aged 10 to 16 from public and private schools.

METHODS

Participants were 190 adolescents selected from public and private schools in Brazil. Neuropsychological measures related to impulsivity (i.e., Barratt Impulsiveness Scale), inhibitory control (i.e., Go/No-go Task), and processing speed (i.e., Five Digits Test) were assessed.

RESULTS

60% of the sample had started drinking alcohol. Early alcohol consumption is not influenced by type of school, indicating that adolescents consume alcohol early, regardless of the type of education or income. Although there were significant differences in neuropsychological performance between types of schools, better neuropsychological performance was found in students from private schools.

CONCLUSIONS

When comparing consumption of alcohol among public and private school students, there were no significant differences, perhaps because the use of early alcohol can be a public health problem. Private school students may perform better in inhibitory control task because they have a good school environment, which serves as a protective factor.

Facets of impulsivity and alcohol use: What role do emotions play?

Alcohol misuse is a major public concern. Impulsivity has been recognised as a significant risk factor predisposing for the initiation of alcohol use, continuation and excessive alcohol use. Evidence suggests that impulsivity is also a result of both acute alcohol intoxication and long-term alcohol abuse. The multifaceted character of impulsivity and the various ways of assessing it in humans and animal models, hampers the full understanding of how impulsivity relates to alcohol use and misuse. Therefore, in this review we evaluate recent developments in the field, trying to disentangle the contribution of different impulsivity subtypes as causes and effects of alcohol use. Moreover, we review a growing body of evidence, including brain imaging, suggesting the importance of emotional states in engaging in alcohol consumption, particularly in highly impulsive individuals. We also present recent insights into how emotional processing is manifested in alcoholism and binge drinking and suggest novel approaches to treatment and prevention opportunities which target emotional-regulation as well as emotional perception and insight.

A Combination of Impulsivity Subdomains Predict Alcohol Intoxication Frequency

BACKGROUND

Impulsivity, broadly characterized as the tendency to act prematurely without foresight, is linked to alcohol misuse in college students. However, impulsivity is a multidimensional construct and different subdomains likely underlie different patterns of alcohol misuse. Here, we quantified the association between alcohol intoxication frequency and alcohol consumption frequency and choice, action, cognitive, and trait domains of impulsivity.

METHODS

University student drinkers (n = 106) completed a battery of demographic and alcohol-related items, as well as self-report and task-based measures indexing different facets of impulsivity. Two orthogonal latent factors, intoxication frequency and alcohol consumption frequency, were generated. Their validity was demonstrated with respect to adverse consequences of alcohol use. Machine learning with penalized regression and feature selection was then utilized to predict intoxication and alcohol consumption frequency using all impulsivity subdomains. Out-of-sample validation was used to quantify model performance.

RESULTS

Impulsivity measures alone were significant predictors of intoxication frequency, but not consumption frequency. Propensity for increased intoxication frequency was characterized by increased trait impulsivity, including the Disinhibition subscale of the Sensation Seeking Scale, Attentional and Non-planning subscales of the Barratt Impulsiveness Scale, increased task-based cognitive impulsivity (response time variability), and increased choice impulsivity (steeper delay discounting on a delay discounting questionnaire). A model combining impulsivity domains with other risk factors (gender; nicotine, cannabis, and other drug use; executive functioning; and learning processes) was also significant but did not outperform the model comprising of impulsivity alone.

CONCLUSIONS

Intoxication frequency, but not consumption frequency, was characterized by a number of impulsivity subdomains.

The GABAA Receptor α2 Subunit Activates a Neuronal TLR4 Signal in the Ventral Tegmental Area that Regulates Alcohol and Nicotine Abuse

Alcoholism initiates with episodes of excessive alcohol drinking, known as binge drinking, which is one form of excessive drinking (NIAAA Newsletter, 2004) that is related to impulsivity and anxiety (Ducci et al., 2007; Edenberg et al., 2004) and is also predictive of smoking status. The predisposition of non-alcohol exposed subjects to initiate binge drinking is controlled by neuroimmune signaling that includes an innately activated neuronal Toll-like receptor 4 (TLR4) signal. This signal also regulates cognitive impulsivity, a heritable trait that defines drug abuse initiation. However, the mechanism of signal activation, its function in dopaminergic (TH+) neurons within the reward circuitry implicated in drug-seeking behavior [viz. the ventral tegmental area (VTA)], and its contribution to nicotine co-abuse are still poorly understood. We report that the γ-aminobutyric acid_A receptor (GABA_AR) α2 subunit activates the TLR4 signal in neurons, culminating in the activation (phosphorylation/nuclear translocation) of cyclic AMP response element binding (CREB) but not NF-kB transcription factors and the upregulation of corticotropin-releasing factor (CRF) and tyrosine hydroxylase (TH). The signal is activated through α2/TLR4 interaction, as evidenced by co-immunoprecipitation, and it is present in the VTA from drug-untreated alcohol-preferring P rats. VTA infusion of neurotropic herpes simplex virus (HSV) vectors for α2 (pHSVsiLA2) or TLR4 (pHSVsiTLR4) but not scrambled (pHSVsiNC) siRNA inhibits signal activation and both binge alcohol drinking and nicotine sensitization, suggesting that the α2-activated TLR4 signal contributes to the regulation of both alcohol and nicotine abuse.

Exploration of Pathways to Binge Drinking Among American Indian Adolescents

Binge drinking is a serious public health problem among American Indian adolescents, yet few theoretical models specific to this population and type of problematic drinking have been tested. The White Mountain Apache Tribe has begun surveillance of binge drinking and a related line of research to inform tailored prevention efforts. The goal of this paper is to use structural equation modeling to understand the relationships between different individual, family, peer, and cultural factors that predict or protect against binge drinking behavior among Apache adolescents ages 10-19 years old. A cross-sectional case-control study was completed with N = 68 Apache adolescents who required medical attention due to a recent binge event (past 90 days) and N = 55 controls with no lifetime history of binge drinking. The hypothesized model was estimated with Mplus using the WLSMV robust least squares estimator. In the final model, stressful life events were related to family functioning and peer relationships. In turn, family functioning affected peer relationships and adolescent impulsivity, which were both associated with greater risk of binge drinking. The path between peer relationships and having engaged in binge drinking was statistically significant for those expressing lower cultural identity, but not for those reporting higher cultural identity. Findings suggest preventive interventions should emphasize teaching coping skills to manage life stressors and handle impulsivity, strengthening families, and changing peer dynamics with social network-based approaches as well as social skill training. The model highlights the potentially important role of culture in strengthening positive peer relationships to reduce binge drinking risk.

Innately activated TLR4 signal in the nucleus accumbens is sustained by CRF amplification loop and regulates impulsivity

Cognitive impulsivity is a heritable trait believed to represent the behavior that defines the volition to initiate alcohol drinking. We have previously shown that a neuronal Toll-like receptor 4 (TLR4) signal located in the central amygdala (CeA) and ventral tegmental area (VTA) controls the initiation of binge drinking in alcohol-preferring P rats, and TLR4 expression is upregulated by alcohol-induced corticotropin-releasing factor (CRF) at these sites. However, the function of the TLR4 signal in the nucleus accumbens shell (NAc-shell), a site implicated in the control of reward, drug-seeking behavior and impulsivity and the contribution of other signal-associated genes, are still poorly understood. Here we report that P rats have an innately activated TLR4 signal in NAc-shell neurons that co-express the α2 GABAA receptor subunit and CRF prior to alcohol exposure. This signal is not present in non-alcohol drinking NP rats. The TLR4 signal is sustained by a CRF amplification loop, which includes TLR4-mediated CRF upregulation through PKA/CREB activation and CRF-mediated TLR4 upregulation through the CRF type 1 receptor (CRFR1) and the MAPK/ERK pathway. NAc-shell Infusion of a neurotropic, non-replicating herpes simplex virus vector for TLR4-specific small interfering RNA (pHSVsiTLR4) inhibits TLR4 expression and cognitive impulsivity, implicating the CRF-amplified TLR4 signal in impulsivity regulation.

Cloninger's Temperament and Character Dimensions of Personality and Binge Drinking Among College Students

BACKGROUND

Temperament and character dimensions of personality remain largely unexplored in young adults exhibiting binge drinking (BD) patterns. Moreover, the available studies do not consider gender differences and dismiss possible personality heterogeneity among binge drinkers. In this study, we aimed to compare temperament and character dimensions between young binge drinkers and age- and sex-matched social drinkers. We further applied cluster analysis to investigate the potential heterogeneity of personality patterns among BD college students.

METHODS

This study included 200 university students of 18 to 24 years of age, who were recruited via an invitation to take an alcohol use survey. These participants included 100 individuals (50 females and 50 males) with a BD pattern, and 100 participants (50 females and 50 males) with a social drinking (SD) pattern. These subjects were evaluated with regard to their use of alcohol and other substances, impulsiveness, sensation seeking, mood, and Cloninger's Temperament and Character Inventory.

RESULTS

Between-group comparisons revealed that both male and female binge drinkers were characterized by high levels of novelty seeking, and low levels of persistence and self-directedness. However, cluster analyses within the binge drinker group revealed 2 distinct groups that differed between males and females. These groups shared similarities with Cloninger's type I (high harm-avoidance) and II (high novelty-seeking) alcoholism typology.

CONCLUSIONS

The present findings support the subdivision of binge drinkers according to gender and personality dimensions. Male and female binge drinkers should not be considered a unitary group, but rather a population of individuals that encompasses at least 2 distinct personality patterns. These findings have major implications for prevention and treatment approaches.

Short-term selection for high and low ethanol intake yields differential sensitivity to ethanol's motivational effects and anxiety-like responses in adolescent Wistar rats

Alcohol use disorders are modulated by genetic factors, but the identification of specific genes and their concomitant biological changes that are associated with a higher risk for these disorders has proven difficult. Alterations in the sensitivity to the motivational effects of ethanol may be one way by which genes modulate the initiation and escalation of ethanol intake. Rats and mice have been selectively bred for high and low ethanol consumption during adulthood. However, selective breeding programs for ethanol intake have not focused on adolescence. This phase of development is associated with the initiation and escalation of ethanol intake and characterized by an increase in the sensitivity to ethanol's appetitive effects and a decrease in the sensitivity to ethanol's aversive effects compared with adulthood. The present study performed short-term behavioral selection to select rat lines that diverge in the expression of ethanol drinking during adolescence. A progenitor nucleus of Wistar rats (F₀) and filial generation 1 (F₁), F₂, and F₃ adolescent rats were derived from parents that were selected for high (STDRHI) and low (STDRLO) ethanol consumption during adolescence and were tested for ethanol intake and responsivity to ethanol's motivational effects. STDRHI rats exhibited significantly greater ethanol intake and preference than STDRLO rats. Compared with STDRLO rats, STDRHI F₂ and F₃ rats exhibited a blunted response to ethanol in the conditioned taste aversion test. F₂ and F₃ STDRHI rats but not STDRLO rats exhibited ethanol-induced motor stimulation. STDRHI rats exhibited avoidance of the white compartment of the light-dark box, a reduction of locomotion, and a reduction of saccharin consumption, suggesting an anxiety-prone phenotype. The results suggest that the genetic risk for enhanced ethanol intake during adolescence is associated with lower sensitivity to the aversive effects of ethanol, heightened reactivity to ethanol's stimulating effects, and enhanced innate anxiety.

Inhibitory control and response monitoring are not systematically related to weekly alcohol consumption in the general population

BACKGROUND

In alcohol use disorder, deficits in cognitive control (i.e., inhibition and response monitoring) might underlie the loss of self-control and, thereby, failure to adjust alcohol consumption in response to associated negative consequences. According to the continuum hypothesis, the magnitude of these deficits should be related in a stair-case manner, with the greatest deficits among its heaviest consumers. The current study aims at investigating this association in the general population.

METHODS

This is a cross-sectional study of 397 participants aged 18-64 years, who self-reported their mean weekly alcohol consumption and were assessed with the stop-signal task, estimating inhibitory efficiency (stop-signal reaction time; SSRT) and response monitoring (post-error slowing; PES). Set-shifting ability was investigated by the intra-extra dimensional (IED) set-shifting task. Three ANCOVAs were performed with SSRT, PES, and IED as the dependent variables (DV), respectively, and alcohol consumption levels as the independent variable. Covariates were included when they were significantly associated with the DV.

RESULTS

Compared to the teetotalers, all levels of alcohol consumption were significantly associated to lower SSRT, which implies more efficient inhibitory control; however, there was no significant difference in SSRT between other consumption levels. The two highest consumption groups had significantly shorter PES when compared to teetotalers and/or the lowest consumption group, implying less behavioral adjustment after failures. IED was not significantly related to the alcohol consumption levels.

CONCLUSIONS

There was no stair-case relation between weekly consumption levels and cognitive control functions within this general population, which might be due to the limited consumption range investigated.

Associations among impulsivity, trauma history, and alcohol misuse within a young adult sample

OBJECTIVE

Young adult alcohol misuse is associated with numerous long-term adverse outcomes. Given the link between impulsivity and alcohol use, we examined whether three impulsivity-related traits differentially predicted number of drinks per drinking day (DDD). We also examined whether these effects varied for those with different trauma histories.

METHOD

The current study (n=254) examined motor, non-planning, and attentional impulsivity as predictors of DDD. It also examined whether impulsivity was differentially predictive of DDD across individuals in: a control group (non-trauma exposed), a trauma exposed but non-PTSD group, and a PTSD group.

RESULTS

Regardless of group, more motor impulsivity was associated with more DDD. The effect of non-planning impulsivity varied according to trauma history. Specifically, more non-planning impulsivity predicted more DDD for those without PTSD. Finally, attentional impulsivity was not predictive of DDD.

CONCLUSIONS

Young adults with high levels of motor impulsivity, regardless of trauma history, may be a particularly high-risk group in terms of propensity for alcohol use/misuse. Additionally, high levels of non-planning impulsivity may signify those at greater risk for alcohol misuse, among those without PTSD. Motor impulsivity and non-planning impulsivity may serve as useful intervention targets in alcohol misuse prevention efforts. Implications for future research in this area are discussed.

Adolescent Alcohol Exposure Persistently Impacts Adult Neurobiology and Behavior

Adolescence is a developmental period when physical and cognitive abilities are optimized, when social skills are consolidated, and when sexuality, adolescent behaviors, and frontal cortical functions mature to adult levels. Adolescents also have unique responses to alcohol compared with adults, being less sensitive to ethanol sedative-motor responses that most likely contribute to binge drinking and blackouts. Population studies find that an early age of drinking onset correlates with increased lifetime risks for the development of alcohol dependence, violence, and injuries. Brain synapses, myelination, and neural circuits mature in adolescence to adult levels in parallel with increased reflection on the consequence of actions and reduced impulsivity and thrill seeking. Alcohol binge drinking could alter human development, but variations in genetics, peer groups, family structure, early life experiences, and the emergence of psychopathology in humans confound studies. As adolescence is common to mammalian species, preclinical models of binge drinking provide insight into the direct impact of alcohol on adolescent development. This review relates human findings to basic science studies, particularly the preclinical studies of the Neurobiology of Adolescent Drinking in Adulthood (NADIA) Consortium. These studies focus on persistent adult changes in neurobiology and behavior following adolescent intermittent ethanol (AIE), a model of underage drinking. NADIA studies and others find that AIE results in the following: increases in adult alcohol drinking, disinhibition, and social anxiety; altered adult synapses, cognition, and sleep; reduced adult neurogenesis, cholinergic, and serotonergic neurons; and increased neuroimmune gene expression and epigenetic modifiers of gene expression. Many of these effects are specific to adolescents and not found in parallel adult studies. AIE can cause a persistence of adolescent-like synaptic physiology, behavior, and sensitivity to alcohol into adulthood. Together, these findings support the hypothesis that adolescent binge drinking leads to long-lasting changes in the adult brain that increase risks of adult psychopathology, particularly for alcohol dependence.

TLR4 signaling in VTA dopaminergic neurons regulates impulsivity through tyrosine hydroxylase modulation

Alcohol dependence is a complex disorder that initiates with episodes of excessive alcohol drinking known as binge drinking, and has a 50-60% risk contribution from inherited susceptibility genes. Cognitive impulsivity is a heritable trait that may set the stage for transition to alcohol dependence but its role in the ethanol-seeking behavior and the involved genes are still poorly understood. We have previously shown that alcohol-preferring P rats have innately elevated levels of a neuronal Toll-like receptor 4 (TLR4) signal in the ventral tegmental area (VTA) that controls the initiation of excessive alcohol drinking. Here we report that TLR4 is localized in dopaminergic (TH+) neurons and it upregulates the expression of tyrosine hydroxylase (TH) through a cAMP-dependent protein kinase (PKA)/cyclic AMP response element binding protein (CREB) signal. P rats have higher impulsivity than wild-type (WT) rats and VTA infusion of a non-replicating Herpes simplex virus (HSV) vector for TLR4-specific small interfering RNA (siRNA; pHSVsiTLR4) inhibits both impulsivity and TLR4/TH expression. A scrambled siRNA vector does not affect gene expression or impulsivity. The data suggest that TLR4 signaling in VTA dopaminergic neurons controls impulsivity related to the regulation of TH expression, likely contributing to the initiation of alcohol drinking and its transition to alcohol dependence.

Interactive Relationships Between Sex-Related Alcohol Expectancies and Delay Discounting on Risky Sex

BACKGROUND

Sex-related alcohol expectancies reflect the degree to which a person believes alcohol will affect her or his sexual behavior. Sex-related alcohol expectancies have been found to be predictors of drinking in sexual situations and engagement in risky sexual behavior after drinking. However, less is known about individual characteristics that may moderate these associations. Building upon recent evidence that steep delay discounting is associated with alcohol-related sexual risk taking, this study aimed to test the hypothesis that the associations between sex-related alcohol expectancies and alcohol-related sexual risk taking would be stronger among individuals who discount delayed rewards more steeply.

METHODS

The current sample comprised 126 Emergency Department patients (Mage  = 27.37; 55% male) who reported high-risk alcohol use and sexual behavior during the past 3 months. Sex-related alcohol expectancies were assessed in 3 behavioral domains: increased riskiness, decreased nervousness, and enhanced sexuality.

RESULTS

All 3 expectancy domains were associated with quantity and frequency of alcohol use, as well as percentage of alcohol-related condomless sex. Delay discounting moderated 2 of these relationships, such that the associations between expectancies for alcohol-induced sexual risk taking and the enhancement of sexuality and percentage of alcohol-related sexual risk-taking were significantly stronger in individuals who exhibited steeper delay discounting.

CONCLUSIONS

These findings suggest that individuals who both discount delayed rewards more steeply and hold strong sex-related alcohol expectancies are a particularly high-risk population. Such individuals may benefit from a combination of novel preventive strategies targeting sex-related alcohol expectancies and impulsive decision making.