Association of EEG alpha variants and alpha power with alcohol dependence in Mexican American young adults

[Features of decision-making in patients with alcohol dependence]

OBJECTIVE

To identify electroencephalographic correlates of decision-making features in patients with alcohol dependence.

MATERIAL AND METHODS

Forty men with alcohol dependence were examined as the main group. Thirty people were examined as a control group. The Cambridge Gambling Task and the Iowa Gambling Task were used to study decision-making functions. Additionally, a background electroencephalogram was recorded with the calculation of absolute spectral power indicators.

RESULTS

In the main group, the relatively higher indicators of decision-making logic (65 [50; 80]%, p<0.05) were associated with larger values of the spectral power of the theta and alpha rhythm of the electroencephalogram in the central and parietal-occipital leads (R=0.426, p=0.019; R=0.418, p=0.022; R=0.394, p=0.028 and R=0.445, p=0.014; R=0.458, p=0.011; R=0.382, p=0.035, respectively). Difficulties in making decisions based on emotional learning in patients with alcohol dependence were associated with larger values of the spectral power of the beta rhythm of the electroencephalogram in the temporal leads.

CONCLUSIONS

The study showed that the deficit of decision-making functions in patients with alcohol dependence may be due to an imbalance of the excitation/inhibition mechanisms in the brain.

Using Anger Management Virtual Reality Cognitive Behavior Therapy to Treat Violent Offenders with Alcohol Dependence in South Korea: A Preliminary Investigation

Cognitive Behavior Therapy (CBT) effectively treats impulse/anger attacks and aggressive-impulsive behaviors, frequently conducted concerning domestic violence, among patients with alcohol dependence. CBT combined with virtual reality (VR) is a new and beneficial psychotherapeutic intervention for patients and violent offenders with impulse-anger control problems and alcohol dependence. This clinical study evaluated the effects of the “anger management virtual reality cognitive behavior therapy (AM-VR-CBT)” and motivational interviewing (MI) intervention program on quantitative electroencephalography (QEEG) mapping patterns among violent offenders with alcohol dependence (N = 29) in the National Probation Service. A clinical sample of twenty-nine violent offenders with alcohol dependence, who were evaluated and diagnosed with destructive and impulse-control disorders (DICD), underwent AM-VR-CBT combined with MI. The sessions lasted 150 minutes (AM-VR-CBT: 90 min; MI: 60 min) and were conducted twice a week for three weeks (six sessions). The intervention outcomes were measured using advanced QEEG brain mapping and standardized neurocognitive, emotional, and behavioral inventories, including the Alcohol Dependence Scale (ADS), the Obsessive Compulsive Drinking Scale (OCDS), the Readiness to Change Questionnaire (RTCQ), the Barratt Impulsiveness Scale-II (BIS-II), the Beck Anxiety Inventory (BAI), the Beck Depression Inventory-Second Edition (BDI-2), and the State-Trait Anger Expression Inventory-2 (STAXI-2), to identify neuro-psycho-physiological changes in violent offenders with alcohol dependence. The Wilcoxon signed-rank test was used at p < 0.05. The intervention showed significant improvements and healthy behavioral changes related to obsessive drinking thoughts, compulsive drinking behaviors, attentional control, intrinsic motivation, worry, anxiety, depression, impulse-anger control issues, aggressive behaviors, over-control, interpersonal relationships, self-efficacy, self-reflection, self-inhibition, creativity, mental navigation/imagery, and episodic memory retrieval among violent offenders with alcohol dependence. Therefore, the results demonstrate the efficacy of the novel and promising clinical evidence-based implementation of the AM-VR-CBT + MI program intervention for non-invasive neuromodulation and related neuro-psycho-physiological, neurocognitive, emotional, and behavioral changes among violent offenders demonstrating alcohol dependence, impulse-anger control, and aggressive behaviors.

Neural correlates of visuoperceptive changes in severe alcohol use disorder: A critical review of neuroimaging and electrophysiological findings

Visuoperceptive deficits are frequently reported in severe alcohol use disorder (SAUD) and are considered as pervasive and persistent in time. While this topic of investigation has previously driven researchers' interest, far fewer studies have focused on visuoperception in SAUD since the '90s, leaving open central questions regarding the origin and implications of these deficits. To renew research in the field and provide a solid background to work upon, this paper reviews the neural correlates of visuoperception in SAUD, based on data from neuroimaging and electrophysiological studies. Results reveal structural and functional changes within the visual system but also in the connections between occipital and frontal areas. We highlight the lack of integration of these findings in the dominant models of vision which stress the dynamic nature of the visual system and consider the presence of both bottom-up and top-down cerebral mechanisms. Visuoperceptive changes are also discussed in the framework of long-lasting debates regarding the influence of demographic and alcohol-related factors, together stressing the presence of inter-individual differences. Capitalizing on this review, we provide guidelines to inform future research, and ultimately improve clinical care.

Alterations of Functional Connectivity During the Resting State and Their Associations With Visual Memory in College Students Who Binge Drink

This study investigated the characteristics of neural oscillation and functional connectivity (FC) in college students engaging in binge drinking (BD) using resting-state electroencephalography (EEG). Also, the associations of visual memory, evaluated by the Rey-Osterrieth Complex Figure Test (RCFT), and neural oscillation with FC during the resting state were investigated. The BD (n = 35) and non-BD (n = 35) groups were selected based on scores of the Korean version of the Alcohol use disorders (AUDs) Identification Test and the Alcohol Use Questionnaire. EEG was performed for 6 min while the participants rested with eyes closed. The theta, lower-alpha, and upper alpha powers did not differ between the BD and non-BD groups. Concerning FC, the BD group exhibited stronger theta coherence than that of the non-BD group, and in the lower and upper alpha bands, the BD group showed stronger coherence in some areas but weaker coherence in others compared with the non-BD group. However, these significant results were not observed after Bonferroni correction. The BD group showed significantly lower delayed recall scores on the RCFT than did the non-BD group. A positive correlation between the left prefrontal-parietal-occipital midline connection and performance on the delayed recall of the RCFT was observed in the BD group. The present results could suggest that binge drinkers have alterations in brain FC, which may be related to their visual memory deficits.

CR-19-0950: Event-related responses to alcohol-related stimuli in Mexican-American young adults: Relation to age, gender, comorbidity and "dark side" symptoms

BACKGROUND

Electrophysiological variables may represent sensitive biomarkers of vulnerability to or endophenotypes for alcohol use disorders (AUD).

METHODS

Young adults (age 18-30 yrs, n = 580) of Mexican American heritage were assessed with the Semi-Structured Assessment for the Genetics of Alcoholism and event-related oscillations (EROs) generated in response to a task that used pictures of objects, food, and alcohol-related and non-alcohol-related drinks as stimuli.

RESULTS

Decreases in energy in the alpha and beta frequencies and higher phase synchrony within cortical brain areas were seen in response to the alcohol-related as compared to the non-alcohol-related stimuli. Differences in ERO energy and synchrony responses to alcohol-related stimuli were also found as a function of age, sex, AUD status and comorbidity. Age-related decreases in energy and increases in synchrony were found. Females had significantly higher energy and lower synchrony values than males. Participants with AUD had higher synchrony values specifically in the beta frequencies, whereas those with a lifetime diagnosis of conduct disorder and/or antisocial personality disorder had lower alpha power and synchrony, and those with any affective disorder had lower ERO energy in the beta frequencies. Those with substance-associated affective "dark-side" symptoms had slower reaction times to the task, lower energy in the beta frequencies, lower local synchrony in the theta frequencies, and higher long-range synchrony in the delta and beta frequencies.

CONCLUSIONS

These findings suggest that EROs recorded to alcohol-related stimuli may be biomarkers of comorbid risk factors, symptoms and disorders associated with AUD that also can differentiate those with "dark-side symptoms".

A review on EEG-based methods for screening and diagnosing alcohol use disorder

The screening test for alcohol use disorder (AUD) patients has been of subjective nature and could be misleading in particular cases such as a misreporting the actual quantity of alcohol intake. Although the neuroimaging modality such as electroencephalography (EEG) has shown promising research results in achieving objectivity during the screening and diagnosis of AUD patients. However, the translation of these findings for clinical applications has been largely understudied and hence less clear. This study advocates the use of EEG as a diagnostic and screening tool for AUD patients that may help the clinicians during clinical decision making. In this context, a comprehensive review on EEG-based methods is provided including related electrophysiological techniques reported in the literature. More specifically, the EEG abnormalities associated with the conditions of AUD patients are summarized. The aim is to explore the potentials of objective techniques involving quantities/features derived from resting EEG, event-related potentials or event-related oscillations data.

Whole genome sequence association and ancestry-informed polygenic profile of EEG alpha in a Native American population

EEG alpha activity is the dominant oscillation in most adult humans, is highly heritable, and has been associated with a number of cognitive functions. Two EEG phenotypes, low- and high-voltage alpha (LVA & HVA), have been demonstrated to have high heritabilities. They have different prevalence depending on a population's ancestral origins. In the present study we assessed the influence of ancestry admixture on EEG alpha power, and conducted a whole genome sequencing association analysis and an ancestry-informed polygenic study on those phenotypes in a Native American (NA) population that has a high prevalence of LVA. Seven common variants, in LD with each other upstream from gene ASIC2, reached genome-wide significance (p = 2 × 10-8 ) having a positive association with alpha voltage. They had lower minor allele frequencies in the NAs than in a global population sample. Overall correlations between lower degrees of NA (higher degree European) ancestry and HVA, and higher degrees of NA and LVA were also found. Additionally a rare-variant gene-based study identified gene TIA1 being negatively associated with LVA. Approximately 3% of SNPs exhibited a 15-fold enrichment that explained nearly half of the total SNP-heritability for EEG alpha. These regions showed the most significant anti-correlations between NA ancestry and alpha voltage, and were enriched for genes and pathways mediating cognitive functions. Our findings suggested that these regions likely harbor causal variants for HVA, and lacking of such variants could explain the high prevalence of LVA in this NA population, possibly illuminating the ancestral origin and genetic basis for EEG alpha.

An EEG-based machine learning method to screen alcohol use disorder

Screening alcohol use disorder (AUD) patients has been challenging due to the subjectivity involved in the process. Hence, robust and objective methods are needed to automate the screening of AUD patients. In this paper, a machine learning method is proposed that utilized resting-state electroencephalography (EEG)-derived features as input data to classify the AUD patients and healthy controls and to perform automatic screening of AUD patients. In this context, the EEG data were recorded during 5 min of eyes closed and 5 min of eyes open conditions. For this purpose, 30 AUD patients and 15 aged-matched healthy controls were recruited. After preprocessing the EEG data, EEG features such as inter-hemispheric coherences and spectral power for EEG delta, theta, alpha, beta and gamma bands were computed involving 19 scalp locations. The selection of most discriminant features was performed with a rank-based feature selection method assigning a weight value to each feature according to a criterion, i.e., receiver operating characteristics curve. For example, a feature with large weight was considered more relevant to the target labels than a feature with less weight. Therefore, a reduced set of most discriminant features was identified and further be utilized during classification of AUD patients and healthy controls. As results, the inter-hemispheric coherences between the brain regions were found significantly different between the study groups and provided high classification efficiency (Accuracy = 80.8, sensitivity = 82.5, and specificity = 80, F-Measure = 0.78). In addition, the power computed in different EEG bands were found significant and provided an overall classification efficiency as (Accuracy = 86.6, sensitivity = 95, specificity = 82.5, and F-Measure = 0.88). Further, the integration of these EEG feature resulted into even higher results (Accuracy = 89.3 %, sensitivity = 88.5 %, specificity = 91 %, and F-Measure = 0.90). Based on the results, it is concluded that the EEG data (integration of the theta, beta, and gamma power and inter-hemispheric coherence) could be utilized as objective markers to screen the AUD patients and healthy controls.

Endophenotype best practices

This review examines the current state of electrophysiological endophenotype research and recommends best practices that are based on knowledge gleaned from the last decade of molecular genetic research with complex traits. Endophenotype research is being oversold for its potential to help discover psychopathology relevant genes using the types of small samples feasible for electrophysiological research. This is largely because the genetic architecture of endophenotypes appears to be very much like that of behavioral traits and disorders: they are complex, influenced by many variants (e.g., tens of thousands) within many genes, each contributing a very small effect. Out of over 40 electrophysiological endophenotypes covered by our review, only resting heart, a measure that has received scant advocacy as an endophenotype, emerges as an electrophysiological variable with verified associations with molecular genetic variants. To move the field forward, investigations designed to discover novel variants associated with endophenotypes will need extremely large samples best obtained by forming consortia and sharing data obtained from genome wide arrays. In addition, endophenotype research can benefit from successful molecular genetic studies of psychopathology by examining the degree to which these verified psychopathology-relevant variants are also associated with an endophenotype, and by using knowledge about the functional significance of these variants to generate new endophenotypes. Even without molecular genetic associations, endophenotypes still have value in studying the development of disorders in unaffected individuals at high genetic risk, constructing animal models, and gaining insight into neural mechanisms that are relevant to clinical disorder.

Lifetime history of traumatic events in a young adult Mexican American sample: Relation to substance dependence, affective disorder, acculturation stress, and PTSD

Mexican Americans comprise one of the most rapidly growing populations in the United States, and within this population, trauma and post-traumatic stress disorder (PTSD) are associated with physical and mental health problems. Therefore, efforts to delineate factors that may uniquely contribute to increased likelihood of trauma, PTSD, and substance use disorders over the lifetime in Mexican Americans are important to address health disparities and to develop treatment and prevention programs. Six hundred fourteen young adults (age 18-30 yrs) of Mexican American heritage, largely second generation, were recruited from the community and assessed with the Semi-Structured Assessment for the Genetics of Alcoholism and an acculturation stress scale. More males (51.2%) reported experiencing traumas than females (41.1%), however, a larger proportion of females received a PTSD diagnosis (15%) than males (8%). Alcohol dependence and affective disorders, but not anxiety disorders, antisocial disorders, nicotine, marijuana, or stimulant dependence, were significantly comorbid with PTSD. Endorsing higher levels of acculturation stress was also significantly associated with both trauma exposure and a diagnosis of PTSD. Logistic regression revealed that female gender, having an affective disorder, alcohol dependence, higher levels of acculturation stress, and lower levels of education were all predictors of PTSD status. Additionally, alcohol dependence generally occurred after the PTSD diagnosis in early adulthood in this high-risk population. These studies suggest that treatment and prevention efforts should particularly focus on young adult second generation Mexican American women with higher levels of acculturation stress, who may be at higher risk for PTSD, affective disorder, and alcohol dependence following trauma exposure.

Genetic variation in FAAH is associated with cannabis use disorders in a young adult sample of Mexican Americans

BACKGROUND

Cannabis is a commonly used drug and studies have shown that a significant portion of the variation in cannabis use disorders (CUDs) is heritable. Five genes known to play a role in the endocannabinoid system and CUDs were examined in a community sample of young adult Mexican Americans (MAs): CNR1, MGLL, FAAH, DAGLA, and DAGLB.

METHODS

Gene-based tests were run to test for association between each gene and two DSM-5 cannabis phenotypes. Subsequent linear regressions were run in PLINK using an additive model to determine which single nucleotide polymorphisms (SNPs) were driving the association.

RESULTS

FAAH was significantly associated with DSM-5 cannabis use disorder group count (DSM-5 CUD) using a gene-based test (p=0.0035). This association survived Bonferroni correction for multiple testing at p<0.004. Post hoc analyses suggested this association was driven by two common (minor allele frequency >5%) SNPs in moderate linkage disequilibrium, rs324420 and rs4141964, at p=0.0014 and p=0.0023, respectively. In both cases the minor allele increased risk for DSM-5 CUD.

CONCLUSIONS

Genetic variation in FAAH was associated with DSM-5 CUD in MAs. This association was primarily driven by the missense SNP rs324420. In vitro work has provided evidence that the risk allele generates an enzyme with decreased expression and cellular stability. Although this SNP has been previously associated with substance use in the literature, this is the first association in a young adult MA sample.

Variants Near CCK Receptors are Associated With Electrophysiological Responses to Pre-pulse Startle Stimuli in a Mexican American Cohort

Neurophysiological measurements of the response to pre-pulse and startle stimuli have been suggested to represent an important endophenotype for both substance dependence and other select psychiatric disorders. We have previously shown, in young adult Mexican Americans (MA), that presentation of a short delay acoustic pre-pulse, prior to the startle stimuli can elicit a late negative component at about 400 msec (N4S), in the event-related potential (ERP), recorded from frontal cortical areas. In the present study, we investigated whether genetic factors associated with this endophenotype could be identified. The study included 420 (age 18-30 years) MA men (n = 170), and women (n = 250). DNA was genotyped using an Affymetrix Axiom Exome1A chip. An association analysis revealed that the CCKAR and CCKBR (cholecystokinin A and B receptor) genes each had a nearby variant that showed suggestive significance with the amplitude of the N4S component to pre-pulse stimuli. The neurotransmitter cholecystokinin (CCK), along with its receptors, CCKAR and CCKBR, have been previously associated with psychiatric disorders, suggesting that variants near these genes may play a role in the pre-pulse/startle response in this cohort.

Low voltage alpha EEG phenotype is associated with reduced amplitudes of alpha event-related oscillations, increased cortical phase synchrony, and a low level of response to alcohol

Low voltage EEG (LVEEG) is a heritable phenotype that differs depending on ancestral heritage, yet its impact on brain networks and cognition remain relatively unexplored. In this study we assessed energy and task related phase locking of event-related oscillation (EROs), behavioral responses, measures of IQ and personality, and expected responses to alcohol in a large sample of individuals with LVEEG compared to those with higher voltage variants. Participants (n=762) were recruited from a Native American community and completed a diagnostic interview, the Quick Test, the Subjective High Assessment Scale Expectation Version (SHAS-E) and the Maudsley Personality Inventory. Clinical and spectral analyzed EEGs were collected for determination of the presence of a LVEEG variant. EROs were generated using a facial expression recognition task. Participants with LVEEG (n=451) were significantly more likely to be older, married and have higher degrees of Native American heritage but did not differ in gender, income or education. Individuals with LVEEG were also found to have decreased energy in their alpha EROs, increased phase locking between stimulus trials, and increased phase-locking between cortical brain areas. No significant differences in the cognitive tests, personality variables or alcohol dependence or anxiety diagnoses were found, however, individuals with LVEEG did report a larger number of drinks ever consumed in a 24-h period and a less intense expected response to alcohol. These data suggest that alpha power in the resting EEG is highly associated with energy and cortical connectivity measures generated by event-related stimuli, as well as potentially increased risk for alcohol use.

Endophenotypes for Alcohol Use Disorder: An Update on the Field

The endophenotype concept was first proposed as a strategy to use (purportedly) genetically simpler phenotypes in gene identification studies for psychiatric disorders, and is distinct from the closely related concept of intermediate phenotypes. In the area of alcohol use disorder (AUD) research, two candidate endophenotypes have produced replicable genetic associations: level of response to alcohol and neurophysiology markers (e.g., event-related oscillations and event-related potentials). Additional candidate endophenotypes from the cognitive, sensory, and neuroimaging literatures show promise, although more evidence is needed to fully evaluate their potential utility. Translational approaches to AUD endophenotypes have helped characterize the underlying neurobiology and genetics of AUD endophenotypes and identified relevant pharmacological interventions. Future research that capitalizes on the polygenic nature of endophenotypes and emphasizes endophenotypes that may change across development will enhance the usefulness of this concept to understand the genetically-influenced pathways toward AUD.

CHRNA5 and CHRNA3 variants and level of neuroticism in young adult Mexican American men and women

A lifetime history of alcohol dependence has been associated with elevations in neuroticism in Mexican American young adults. The identification of genetic markers associated with neuroticism and their influence on the development of alcohol use disorders (AUD) may contribute to our understanding of the relationship between personality traits and the increased risk of AUD in Mexican Americans. The purpose of this study was to investigate associations between neuroticism and 13 single nucleotide polymorphisms (SNPs) in the nicotinic acetylcholine (nAChR) α5-subunit (CHRNA5) and α3-subunit (CHRNA3) genes in young adult Mexican American men and women. Participants were 465 young adult Mexican American men and women who are literate in English and are residing legally in San Diego County. Each participant gave a blood sample and completed a structured diagnostic interview. Neuroticism was assessed using the Maudsley Personality Inventory. The minor alleles of four CHRNA5 polymorphisms (rs588765, rs601079, rs680244 and rs555018) and three CHRNA3 polymorphisms (rs578776, rs6495307 and rs3743078) showed associations with neuroticism. Several of these SNPs also displayed nominal associations with DSM-IV alcohol and nicotine dependence, but tests of mediation suggested that these relations could be partially explained by the presence of co-occurring neuroticism. These findings suggest that genetic variations in nicotinic receptor genes may influence the development of neuroticism, which in turn is involved in the development of AUDs and nicotine dependence in Mexican American young adults.

N4 component responses to pre-pulse startle stimuli in young adults: relationship to alcohol dependence

Both physiological and behavioral studies provide evidence to suggest that deficits in frontal cortical control circuits may contribute to the risk for developing alcohol dependence. Event-related potential (ERP) and eye blink responses to startle and short delay prepulse-plus-startle stimuli, and psychiatric diagnoses were investigated in young adult (age 18-30 years) men (n=135) and women (n=205) Mexican Americans. Women displayed a significant increase in the amplitude of the eye blink response to both the startle and pre-pulse-plus-startle stimuli. None of the psychiatric diagnoses were associated with differences in eye blink responses. ERP responses to the startle and prepulse-plus startle stimuli included a negative polarity wave at approximately 400 ms that was of the highest amplitude in the frontal leads (N4S). Women were found to have significantly higher amplitude N4S responses than men. Participants with alcohol dependence demonstrated significantly less inhibition and more facilitation of the N4S component by the pre-pulse stimuli. This finding was not associated with a diagnosis of: any other drug dependence disorder (including nicotine), anxiety or affective disorder, or conduct/antisocial personality disorder. The present study suggests that gender and a lifetime diagnosis of alcohol dependence may selectively contribute to this frontal late wave electrophysiological response to prepulse-plus-startle stimuli.

EEG spectral phenotypes: heritability and association with marijuana and alcohol dependence in an American Indian community study

Native Americans have some of the highest rates of marijuana and alcohol use and abuse, yet neurobiological measures associated with dependence on these substances in this population remain unknown. The present investigation evaluated the heritability of spectral characteristics of the electroencephalogram (EEG) and their correlation with marijuana and alcohol dependence in an American Indian community. Participants (n=626) were evaluated for marijuana (MJ) and alcohol (ALC) dependence, as well as other psychiatric disorders. EEGs were collected from six cortical sites and spectral power determined in five frequency bands (delta 1.0-4.0 Hz, theta 4.0-7.5 Hz, alpha 7.5-12.0 Hz, low beta 12.0-20.0 Hz and high beta/gamma 20-50 Hz). The estimated heritability (h(2)) of the EEG phenotypes was calculated using SOLAR, and ranged from 0.16 to 0.67. Stepwise linear regression was used to detect correlations between MJ and ALC dependence and the spectral characteristics of the EEG using a model that took into account: age, gender, Native American Heritage (NAH) and a lifetime diagnosis of antisocial personality and/or conduct disorder (ASPD/CD). Increases in spectral power in the delta frequency range, were significantly correlated with gender (p<0.001) and marijuana dependence (p<0.003). Gender, age, NAH and ASPD/CD were all significantly (p<0.001) correlated with theta, alpha and beta band power, whereas alcohol dependence (p<0.01), gender (p<0.001), and ASPD/CD (p<0.001) were all correlated with high beta/gamma band power. These data suggest that the traits of EEG delta and high beta/gamma activity are correlated with MJ dependence and alcohol dependence, respectively, in this community sample of Native Americans.

HTR3B is associated with alcoholism with antisocial behavior and alpha EEG power--an intermediate phenotype for alcoholism and co-morbid behaviors

Alcohol use disorders (AUD) with co-morbid antisocial personality disorder (ASPD) have been associated with serotonin (5-HT) dysfunction. 5-HT3 receptors are potentiated by ethanol and appear to modulate reward. 5-HT3 receptor antagonists may be useful in the treatment of early-onset alcoholics with co-morbid ASPD. Low-voltage alpha electroencephalogram (EEG) power, a highly heritable trait, has been associated with both AUD and ASPD. A recent whole genome linkage scan in one of our samples, Plains American Indians (PI), has shown a suggestive linkage peak for alpha power at the 5-HT3R locus. We tested whether genetic variation within the HTR3A and HTR3B genes influences vulnerability to AUD with comorbid ASPD (AUD+ASPD) and moderates alpha power. Our study included three samples: 284 criminal alcoholic Finnish Caucasians and 234 controls; two independent community-ascertained samples with resting EEG recordings: a predominantly Caucasian sample of 191 individuals (Bethesda) and 306 PI. In the Finns, an intronic HTR3B SNP rs3782025 was associated with AUD+ASPD (P=.004). In the Bethesda sample, the same allele predicted lower alpha power (P=7.37e(-5)). Associations between alpha power and two other HTR3B SNPs were also observed among PI (P=.03). One haplotype in the haplotype block at the 3' region of the gene that included rs3782025 was associated with AUD+ASPD in the Finns (P=.02) and with reduced alpha power in the Bethesda population (P=.00009). Another haplotype in this block was associated with alpha power among PI (P=.03). No associations were found for HTR3A. Genetic variation within HTR3B may influence vulnerability to develop AUD with comorbid ASPD. 5-HT3R might contribute to the imbalance between excitation and inhibition that characterize the brain of alcoholics.