DRD4 polymorphism moderates the effect of alcohol consumption on social bonding

The impact of alcohol consumption on implicit racial bias

OBJECTIVE

Researchers and theorists studying intergroup relations have been interested in the impact of alcohol on interracial responding. Theories predict that alcohol will exacerbate expressions of racial bias by increasing reliance on stereotypes and/or by decreasing controlled processing and self-monitoring. Prior studies testing these theories have often examined alcohol's effects on implicit (i.e., indirect) measures of racial bias with inconsistent results. However, previous research in this area has suffered from several methodological limitations, including small sample sizes and doses of alcohol that may have been too low to induce substantial intoxication.

METHOD

Here, in more than triple the number of alcohol participants than the largest prior study, we tested whether an intoxicating dose of alcohol (target breath alcohol concentration of .08%) exacerbated implicit racial bias. Young adults who identified as races other than Black or African American (N = 207) were randomly assigned to consume an alcoholic or placebo beverage and completed the race-based Implicit Association Test (race IAT) testing implicit preference for White (vs. Black) individuals [or, conversely, bias against Black (vs. White) individuals].

RESULTS

All participants demonstrated an implicit racial bias (i.e., linking traditionally Black names with negative/unpleasant words), with no difference in this implicit racial bias across beverage conditions. Specifically, there were no differences between alcohol participants' race IAT D scores (M = 0.55, SD = 0.39), and placebo participants' race IAT D scores (M = 0.59, SD = 0.35), b = 0.05, 95%CI [-0.07, 0.18], p = .422.

CONCLUSIONS

These findings challenge theories and prior studies suggesting that alcohol increases implicit racial bias. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

A systematic review of the acute effects of alcohol on emotion recognition of facial expressions

Alcohol has been linked to both positive (e.g., sociability) and negative (e.g., aggression) social outcomes, and researchers have proposed that alcohol-induced changes in emotion recognition may partially explain these effects. Here, we systematically review alcohol administration studies to clarify the acute effects of alcohol on emotion recognition. We also investigate various moderator variables (i.e., sex, study quality, study design, alcohol dosage, emotion recognition task and outcome measure). PsycINFO, PubMed and Google Scholar were searched following a pre-registered PROSPERO protocol (CRD42021225392) and PRISMA methodology. Analyses focused on differences in emotion recognition between participants consuming alcoholic and/or non-alcoholic (i.e., placebo or no-alcohol control) beverages. Nineteen unique samples (N = 1271 participants) were derived from 17 articles (two articles included two studies, each conducted on a unique sample). Data were extracted for sample characteristics, alcohol administration methods and emotion recognition tasks and outcomes. All studies compared an alcoholic beverage to a placebo beverage and used tasks that asked participants to identify emotions from images or videos of facial expressions. Otherwise, methodologies varied substantially across studies, including the alcohol dosage(s) tested, the specific emotion recognition task(s) used and the outcome variable(s) assessed. No consistent effects of alcohol on emotion recognition emerged for any emotion. None of the moderator variables affected the findings, except for some indication that alcohol may affect males' emotion recognition abilities more so than females. Alcohol does not appear to consistently affect positive or negative emotion recognition of facial expressions, at least with the tasks currently used in the field.

Self-management with alcohol over lifespan: psychological mechanisms, neurobiological underpinnings, and risk assessment

Self-management includes all behavioural measures and cognitive activities aimed at coping with challenges arising throughout the lifespan. While virtually all of these challenges can be met without pharmacological means, alcohol consumption has long been instrumentalized as a supporting tool to help coping with problems arising selectively at adolescence, adulthood, and ageing. Here, we present, to our knowledge, the first systematic review of alcohol instrumentalization throughout lifespan. We searched MEDLINE, Google Scholar, PsycINFO and CINAHL (from Jan, 1990, to Dec, 2022) and analysed consumption patterns, goals and potential neurobiological mechanisms. Evidence shows a regular non-addictive use of alcohol to self-manage developmental issues during adolescence, adulthood, and ageing. Alcohol is selectively used to overcome problems arising from dysfunctional personality traits, which manifest in adolescence. A large range of psychiatric disorders gives rise to alcohol use for the self-management of distinct symptoms starting mainly in adulthood. We identify those neuropharmacological effects of alcohol that selectively serve self-management under specific conditions. Finally, we discuss the adverse effects and associated risks that arise from the use of alcohol for self-management. Even well-controlled alcohol use adversely impacts health. Based on these findings, we suggest the implementation of an entirely new view. Health policy action may actively embrace both sides of the phenomenon through a personalized informed use that allows for harm-controlled self-management with alcohol.

Meta-analysis of associations between empathy and alcohol use and problems in clinical and non-clinical samples

AIMS

To (1) measure the aggregated effect size of empathy deficits in individuals with alcohol use disorder (AUD) compared with healthy controls, (2) measure the aggregated effect sizes for associations between lower empathy and heavier alcohol consumption and more alcohol problems in non-clinical samples and (3) identify potential moderators on the variability of effect sizes across studies in these meta-analyses.

METHOD

PsycINFO, PubMed and Google Scholar were searched following a pre-registered International Prospective Register of Systematic Reviews (PROSPERO) protocol (CRD42021225392) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. We meta-analyzed (using random-effects models) mean differences in empathy between individuals with AUD compared with healthy controls and associations between empathy and alcohol consumption and alcohol problems in non-clinical samples. A total of 714 participants were included in the meta-analysis on clinical samples; 3955 were included in the meta-analyses on non-clinical samples.

RESULTS

Individuals with AUD reported significantly lower empathy than healthy controls [Hedges' g = -0.53, 95% confidence interval (CI) = -0.91, -0.16, k = 9, P < 0.01, Q = 40.09, I2  = 80.04]. Study quality [Q = 1.88, degrees of freedom (d.f.) = 1, P = 0.17] and gender (β = -0.006, Z = -0.60, P = 0.55) were not moderators. Increases in age corresponded to an increase in effect size (β = 0.095, Z = 3.34, P < 0.001). Individuals with AUD (versus healthy controls) had significantly lower cognitive (Hedges' g = -0.44, CI = -0.79, -0.10, P < 0.05), but not affective empathy (Hedges' g = -0.19, CI = -0.51, 0.14, P = 0.27), and the difference between these was significant (Z = 2.34, k = 6, P < 0.01). In non-clinical samples, individuals with lower (versus higher) empathy reported heavier alcohol consumption (r = -0.12, CI = -0.15, -0.09, k = 11, P < 0.001, Q = 9.68, I2  = 0.00) and more alcohol problems (r = -0.08, CI = -0.14, -0.01, k = 7, P = 0.021, Q = 6.55, I2  = 8.34). There was no significant heterogeneity across studies.

CONCLUSION

Individuals with alcohol use disorder appear to show deficits in empathy compared with healthy controls. Deficits are particularly pronounced for older individuals and for cognitive (versus affective) empathy. In non-clinical samples, lower empathy appears to be associated with heavier alcohol consumption and more alcohol problems.

Systematic review and meta-analysis on the association between theory of mind and alcohol problems in non-clinical samples

BACKGROUND

Deficits in theory of mind (ToM) found in individuals with alcohol use disorder (AUD) are often thought to result from prolonged heavy alcohol use. However, links between deficits in ToM and greater alcohol problems are often also present in non-clinical samples (e.g., adolescents and young adults) who may not have a similar long-lasting history of alcohol consumption as individuals with AUD. The current study is the first to systematically review and meta-analyze results from studies examining associations between lower ToM and greater alcohol problems in non-clinical samples. Evidence of reliable associations in these non-clinical samples would support the idea that deficits in ToM might also precede the emergence of AUD.

METHODS

PsycINFO, PubMed, and Google Scholar were searched according to our preregistered International Prospective Register of Systematic Reviews (PROSPERO) protocol (CRD42021225392) and following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. We systematically reviewed sample characteristics and ToM measures in identified articles. We then meta-analyzed the findings of association between ToM and alcohol problems in non-clinical samples using random effects models.

RESULTS

Nearly all studies used a measure of ToM that assessed the ability to infer the mental states of others based on eye region cues. Meta-analytic results demonstrated that lower ToM was associated with more alcohol problems (r = -0.16, k = 6, CI = [-0.26, -0.04], p < 0.01, Q = 15.55, I²  = 67.85), and there was significant heterogeneity across studies. Gender (ß = 0.0003, CI = [-0.006, 0.007], z = 0.09, p = 0.93), age (ß = -0.008, CI = [-0.03, 0.01], z = -0.82, p = 0.42), and study quality (ß = -0.10, CI = [-0.35, 0.15], z = -0.82, p = 0.41) did not explain the heterogeneity.

CONCLUSION

In non-clinical samples, lower ToM is associated with more alcohol problems, indicative of a small effect size. Future longitudinal studies are needed to explore whether socio-cognitive deficits may also serve as a risk factor for alcohol misuse.

Mixing Misery and Gin: The Effect of Alcohol Administration on Ostracism Response

Williams's need-threat model proposes that ostracism responses are reflexive and, because of their evolutionary significance, difficult to diminish. Alcohol is widely consumed in social contexts and for reasons of coping with social stress, and major theories of alcohol propose that intoxication disrupts cognitive appraisal of environmental threats, leading to stress relief. Surprisingly, though, no well-powered experimental research has examined the impact of alcohol intoxication on distress from social ostracism. In three studies across two independent laboratories (N = 438), participants were randomly assigned to receive either an alcoholic or nonalcoholic (i.e., no-alcohol control or placebo) beverage and were exposed to an ostracism (or social inclusion) manipulation. Results, which emerged as remarkably consistent across all studies, indicated strong and consistent effects of ostracism on mood and needs satisfaction among both intoxicated and sober participants. Findings have important implications for ostracism theory and speak to boundary conditions for alcohol's ability to relieve stress.

ADHD co-morbidities: A review of implication of gene × environment effects with dopamine-related genes

ADHD is a major burden in adulthood, where co-morbid conditions such as depression, substance use disorder and obesity often dominate the clinical picture. ADHD has substantial shared heritability with other mental disorders, contributing to comorbidity. However, environmental risk factors exist but their interaction with genetic makeup, especially in relation to comorbid disorders, remains elusive. This review for the first time summarizes present knowledge on gene x environment (GxE) interactions regarding the dopamine system. Hitherto, mainly candidate (GxE) studies were performed, focusing on the genes DRD4, DAT1 and MAOA. Some evidence suggest that the variable number tandem repeats in DRD4 and MAOA may mediate GxE interactions in ADHD generally, and comorbid conditions specifically. Nevertheless, even for these genes, common variants are bound to suggest risk only in the context of gender and specific environments. For other polymorphisms, evidence is contradictory and less convincing. Particularly lacking are longitudinal studies testing the interaction of well-defined environmental with polygenic risk scores reflecting the dopamine system in its entirety.

The influence of negative mood on solitary drinking preference: An experiment with young adult solitary drinkers

Solitary drinking is a risk marker for alcohol use disorder; thus, it is important to identify why individuals drink alone and for whom this association is particularly relevant. Evidence suggests the desire to ameliorate negative affect (NA) motivates solitary drinking, with some individuals particularly likely to drink alone to cope, but all past studies are cross-sectional. The present study therefore aimed to determine whether 1) experimentally induced NA increased preferences to drink alcohol alone, and 2) whether the relationship between NA and choosing to drink alcohol alone was moderated by neuroticism, drinking to cope motives, and social anxiety. Current drinkers (ages 21-29) with a solitary drinking history (N=126) were randomly assigned to either NA, positive affect [PA], or no affect change (control) conditions via differing cognitive task feedback. After the mood manipulation, participants chose between drinking alcoholic or nonalcoholic beverages in one of two contexts: alone or socially. Evidence regarding effectiveness of the mood manipulation was mixed, and few chose non-alcoholic beverages in either context. Condition did not influence outcome choice. Across conditions, increases in NA and the importance placed on receiving one's context choice were associated with solitary (versus social) alcohol preference. Neuroticism and its interaction with NA change also influenced choice; individuals high in neuroticism chose more solitary (versus social) drinking contexts while the opposite was true for those low in neuroticism, and among the latter, the preference difference was more pronounced with relatively smaller NA increases. Findings are discussed based on the existing solitary drinking literature.

Drinking Together and Drinking Alone: A Social-Contextual Framework for Examining Risk for Alcohol Use Disorder

The context in which drinking occurs is a critical but relatively understudied factor in alcohol use disorder (AUD) etiology. In this article, I offer a social-contextual framework for examining AUD risk by reviewing studies on the unique antecedents and deleterious consequences of social versus solitary alcohol use in adolescents and young adults. Specifically, I provide evidence of distinct emotion regulatory functions across settings, with social drinking linked to enhancing positive emotions and social experiences and solitary drinking linked to coping with negative emotions. I end by considering the conceptual, methodological, and clinical implications of this social-contextual account of AUD risk.

DRD4 polymorphisms modulate reward positivity and P3a in a gambling task: Exploring a genetic basis for cultural learning

Prior work shows that people respond more plastically to environmental influences, including cultural influences, if they carry the 7 or 2-repeat (7/2R) allelic variant of the dopamine D4 receptor gene (DRD4). The 7/2R carriers are thus more likely to endorse the norms and values of their culture. So far, however, mechanisms underlying this moderation of cultural acquisition by DRD4 are unclear. To address this gap in knowledge, we tested the hypothesis that DRD4 modulates the processing of reward cues existing in the environment. About 72 young adults, preselected for their DRD4 status, performed a gambling task, while the electroencephalogram was recorded. Principal components of event-related potentials aligned to the Reward-Positivity (associated with bottom-up processing of reward prediction errors) and frontal-P3 (associated with top-down attention) were both significantly more positive following gains than following losses. As predicted, the gain-loss differences were significantly larger for 7/2R carriers than for noncarriers. Also, as predicted, the cultural backgrounds of the participants (East Asian vs. European American) did not moderate the effects of DRD4. Our findings suggest that the 7/2R variant of DRD4 enhances (a) the detection of reward prediction errors and (b) controlled attention that updates the context for the reward, thereby suggesting one possible mechanism underlying the DRD4 × Culture interactions.

Genetic Polymorphisms on OPRM1, DRD2, DRD4, and COMT in Young Adults: Lack of Association With Alcohol Consumption

Background: Risk behaviors for young adults such as alcohol use are associated with increased risk of morbidity and mortality. Patterns of risk behavior may be genetically determined and vary between genders. Previous studies in both young adults and heavy drinking adult samples have demonstrated that some genotypes, such as OPRM1 A118G, COMT Val158Met and DRD2 Taq1A and DRD4 C52IT, may predict addictive behaviors including alcohol consumption and impulsivity, although results have been mixed. Methods: This study aimed to investigate the predictive relationship of these four single nucleotide polymorphisms (SNPs) prospectively on student patterns of drinking using a micro-longitudinal daily diary design in a sample of 628 young adults ages 18-25 of predominantly of European ethnicity. Linear mixed models were used to examine the effect of SNPs on the number of drinks per drinking session with gender as a moderating variable. Results: There were no main effects for genotype on alcohol consumption, nor for gender × genotype for any of the SNPs. There was a trend for an effect of the DRD2 Taq1A on the number of drinks per drinking day and for the interaction of gender and DRD2 Taq1A on the number of drinks per drinking day. Conclusion: These findings suggest that the DRD2 Taq1A, OPRM1 A118G, DRD4 C521T, or COMT Val158Met polymorphisms, are not associated with alcohol consumption in young adults, although there may be a relationship between DRD2 Taq1A and alcohol consumption in young adult males.

Neuropharmacological and Neurogenetic Correlates of Opioid Use Disorder (OUD) As a Function of Ethnicity: Relevance to Precision Addiction Medicine

BACKGROUND

Over 100 people die daily from opioid overdose and $78.5B per year is spent on treatment efforts, however, the real societal cost is multifold greater. Alternative strategies to eradicate/manage drug misuse and addiction need consideration. The perception of opioid addiction as a social/criminal problem has evolved to evidence-based considerations of them as clinical disorders with a genetic basis. We present evaluations of the genetics of addiction with ancestryspecific risk profiles for consideration.

OBJECTIVE

Studies of gene variants associated with predisposition to substance use disorders (SUDs) are monolithic, and exclude many ethnic groups, especially Hispanics and African Americans. We evaluate gene polymorphisms that impact brain reward and predispose individuals to opioid addictions, with a focus on the disparity of research which includes individuals of African and Hispanic descent.

METHODOLOGY

PubMed and Google Scholar were searched for: Opioid Use Disorder (OUD), Genome- wide association studies (GWAS); genetic variants; polymorphisms, restriction fragment length polymorphisms (RFLP); genomics, epigenetics, race, ethnic group, ethnicity, ancestry, Caucasian/ White, African American/Black, Hispanic, Asian, addictive behaviors, reward deficiency syndrome (RDS), mutation, insertion/deletion, and promotor region.

RESULTS

Many studies exclude non-White individuals. Studies that include diverse populations report ethnicity-specific frequencies of risk genes, with certain polymorphisms specifically associated with Caucasian and not African-American or Hispanic susceptibility to OUD or SUDs, and vice versa.

CONCLUSION

To adapt precision medicine-based addiction management in a blended society, we propose that ethnicity/ancestry-informed genetic variations must be analyzed to provide real precision- guided therapeutics with the intent to attenuate this uncontrollable fatal epidemic.

Association of the DRD4 exon III and 5-HTTLPR VNTR polymorphisms with substance abuse in Jordanian Arab population

Genetic variations in the dopamine D4 receptor (DRD4) gene and the serotonin transporter (SLC6A4) gene are involved in the aetiology of substance abuse disorder (SUD). The main aim of this study is to evaluate the genetic association of DRD4 (48 bp-VNTR) and SLC6A4 (rs25531 and 5-HTTLPR VNTR) gene polymorphisms with SUD susceptibility among the Jordanian Arab population. This study included 500 SUD patients and 500 healthy matched controls. The VNTR Genetic polymorphisms of DRD4 and SLC6A4 genes were genotyped using conventional polymerase chain reaction (PCR). While, the rs25531 SNP was genotyped using PCR-restriction fragment length polymorphism (PCR-RFLP) technique. The genetic association was analysed using different statistical analyses including chi-square, Fisher exact test and one way ANOVA test. The DRD4 exon III VNTR polymorphism was associated with SUD significantly in case of alleles 4, 7 and genotype 7/7 (P = 0.004, 0.0005 and 0.01, respectively). While, there was no genetic association between the 5-HTTLPR (LL, LS, SS), rs25331 (AA, AG, GG) and tri-allelic (SASA, LASG, LASA, LALG, LALA) genotypes (P = 0.26, 0.71 and 0.52, respectively) and SUD. Moreover, using multinomial regression analysis, the homozygous 7/7 and 2/2 VNTR genotypes of DRD4 gene were nominally significantly associated with a lower risk of addiction (OR = 0.285 with P = 0.003 and OR = 0.447 with P = 0.031, respectively) after adjusting for other covariates. Our findings showed that 4 and 7 repeats and the genotype 7/7 of DRD4 exon III VNTRs polymorphism are involved in the aetiology of SUD among Jordanian population in compared to the 5-HTTLPR polymorphisms.

A multimodal investigation of contextual effects on alcohol's emotional rewards

Regular alcohol consumption in unfamiliar social settings has been linked to problematic drinking. A large body of indirect evidence has accumulated to suggest that alcohol's rewarding emotional effects-both negative-mood relieving and positive-mood enhancing-will be magnified when alcohol is consumed within unfamiliar versus familiar social contexts. But empirical research has never directly examined links between contextual familiarity and alcohol reward. In the current study, we mobilized novel ambulatory technology to examine the effect of social familiarity on alcohol reward in everyday drinking contexts while also examining how alcohol reward observed in these field contexts corresponds to reward observed in the laboratory. Heavy social drinking participants (N = 48, 50% male) engaged in an intensive week of ambulatory assessment. Participants wore transdermal alcohol sensors while they reported on their mood and took photographs of their social contexts in response to random prompts. Participants also attended 2 laboratory beverage-administration sessions, during which their emotional responses were assessed and transdermal sensors were calibrated to estimate breathalyzer readings (eBrACs). Results indicated a significant interaction between social familiarity and alcohol episode in everyday drinking settings, with alcohol enhancing mood to a greater extent in relatively unfamiliar versus familiar social contexts. Findings also indicated that drinking in relatively unfamiliar social settings was associated with higher eBrACs. Finally, results indicated a correspondence between some mood effects of alcohol experienced inside and outside the laboratory. This study presents a novel methodology for examining alcohol reward and indicates social familiarity as a promising direction for research seeking to explain problematic drinking. (PsycINFO Database Record

Using Placebo Beverages in Group Alcohol Studies

BACKGROUND

Placebo beverage conditions remain a key element in the methodological toolkit for alcohol researchers interested in evaluating pharmacological and nonpharmacological factors influencing the effects of alcohol consumption. While interest in experimentally examining alcohol in social context is on the rise, there has been little research examining the effectiveness of placebo manipulations in group settings, when just 1 suspicious participant could potentially jeopardize the effect of the placebo on group members. Moreover, research has rarely considered the association between individual difference factors (e.g., gender) and placebo manipulation effectiveness. The present study, using an uncommonly large sample of placebo-consuming participants, was well suited to investigate fundamental questions regarding placebo efficacy that have not been assessed previously. Specifically, we aimed to examine placebo efficacy and general processes of placebo functioning in a group context. We also assessed potential associations between a variety of individual difference factors and placebo response.

METHODS

A total of 240 participants (50% male) consumed placebo beverages during a triadic drinking period (across 80 three-person groups). Participants reported their subjective intoxication, stimulation, and sedation 8 minutes following drink consumption and estimated the alcohol content of their drink at the end of the study.

RESULTS

Participants consuming placebo beverages in groups were nearly universal in reporting that they had consumed alcohol (>99%) and had experienced an increase in feelings of intoxication [t(239) = 22.03, p < 0.001] and stimulation [t(239) = 5.53, p < 0.001], levels that were similar to those observed in prior studies conducted with participants drinking placebos in isolation. Further, participants' placebo responses were independent of their 2 group members and were largely unaffected by a variety of individual difference factors.

CONCLUSIONS

Placebo response generally operated independently of group-member influences, suggesting that researchers can successfully conduct placebo beverage studies utilizing group drinking designs.

The effects of alcohol on positive emotion during a comedy routine: A facial coding analysis

There is considerable interest in understanding the emotional effects of alcohol. While a great deal of experimental research has focused on alcohol's ability to relieve negative emotions, there has been far less focus on the effects of alcohol on positive emotions. Further, the available research on positive emotion tends to test alcohol while participants are alone. Yet alcohol is often consumed in social settings, and enhancing social pleasure is consistently identified as being a primary motive for drinking. We aimed to address this gap in the literature by investigating the impact of alcohol on positive emotional experience in a social setting. We used the Facial Action Coding System (FACS) to examine in a large sample the effects of alcohol on response to comedy in a group setting. Five hundred thirteen social drinkers (51.9% female) were assembled into groups of three unacquainted persons and administered either a moderate dose of alcohol, a placebo, or a nonalcohol control beverage. Following beverage consumption, groups listened to a roughly 5-min comedy clip while their facial expressions were video recorded. More than 5 million frames of video were then FACS-coded. Alcohol consumption enhanced enjoyment (Duchenne) smiles-but not nonenjoyment social smiles-and elevated mood ratings. Results provide multimodal evidence supporting the ability of alcohol to enhance positive emotional experience during a comedy routine delivered in a social context. More broadly, this research illustrates the value of studying emotion in a social context using both self-report and behavior-expressive approaches. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Transactions Between Substance Use Intervention, the Oxytocin Receptor (OXTR) Gene, and Peer Substance Use Predicting Youth Alcohol Use

This study investigated the oxytocin receptor (OXTR) gene's moderation of associations between exposure to a substance misuse intervention, average peer substance use, and adolescents' own alcohol use during the 9th-grade. OXTR genetic risk was measured using five single nucleotide polymorphisms (SNPs), and peer substance use was based on youths' nominated closest friends' own reports of alcohol, cigarette, and marijuana use, based on data from the PROSPER project. Regression models revealed several findings. First, low OXTR risk was linked to affiliating with friends who reported less substance use in the intervention condition but not the control condition. Second, affiliating with high substance-using friends predicted youth alcohol risk regardless of OXTR risk or intervention condition. Third, although high OXTR risk youth in the intervention condition who associated with low substance-using friends reported somewhat higher alcohol use than comparable youth in the control group, the absolute level of alcohol use among these youth was still among the lowest in the sample.

Interaction Between the μ-Opioid Receptor Gene and the Number of Heavy-Drinking Peers on Alcohol Use

BACKGROUND

The presence of heavy-drinking peers may trigger genetic vulnerabilities to alcohol use. Limited correlational findings, albeit mixed as a function of age, suggest that carriers of a μ-opioid receptor (OPRM1) G allele may be more vulnerable than noncarriers to alcohol-promoting perceived peer environments. However, research has not yet examined such genetic susceptibility to actual (rather than perceived) peer environments through an experimental, ad libitum alcohol administration design. This study examined whether OPRM1 modulates the effects of heavy-drinking group size on alcohol consumption and explored potential mediators of such OPRM1-based differences.

METHODS

Caucasian young adult moderate to heavy drinkers (N = 116; mean age = 22 years [SD = 2.21], 49% female) were randomly assigned to consume alcohol in the presence of none, 1, or 3 heavy-drinking peer confederates.

RESULTS

Results showed no significant moderating effects of OPRM1 in the relationship between the number (or presence) of heavy-drinking peers and voluntary alcohol consumption (partial η2  = 0.01). This result remained the same after controlling for sex, age, and typical drinking quantity as well as their 2-way interactions with OPRM1 and social drinking condition. In addition, OPRM1 did not moderate the peer influence on any proposed mediating variables, including craving for alcohol and subjective responses to alcohol.

CONCLUSIONS

Findings suggest no OPRM1-based susceptibility to the number of heavy-drinking peers, adding to the existing mixed findings from correlational studies. Future research on OPRM1-related susceptibility to alcohol-promoting peer environments through meta-analytic synthesis and both experimental and prospective, multiwave designs is needed to resolve these mixed findings.

The case for investigating social context in laboratory studies of smoking

BACKGROUND

With increasing frequency, addiction is conceived of as a brain disease, and such accounts seem especially pertinent with regard to the rapid delivery of nicotine to the brain via cigarette smoke. Moreover, drug administration trials (cigarette puffs) suggest that the behavior of smoking becomes automatized, with individuals developing prototypical approaches to smoking a cigarette. Compared with presumably more social activities, such as drinking alcohol, there may be little opportunity for social processes to influence smoking behavior. However, survey research examining smoking motivation often reveals a broadly defined 'social' factor and field research suggests that social context does influence smoking.

ARGUMENT

We posit that laboratory smoking research has largely ignored social contextual factors that may help to understand better the precise mechanisms underlying smoking behavior and smoking motivation.

METHOD

We reviewed laboratory studies examining the effect of social context (operationalized as modeling) on smoking behavior. Studies were identified by searching PsychInfo and Medline using the following keywords: smoking, nicotine, tobacco, cigarette, consumption, topography, puff, smoking behavior, cigarettes smoked, modeling, imitation, social context, social influence and peer pressure. The reference and citation lists of these studies were then searched to identify additional studies.

CONCLUSIONS

Few laboratory smoking studies target social context. Those few studies indicate that smoking behavior can be influenced by the presence of others. There is also some evidence that social context influences the effects of smoking as well as processes related to self-perception and self-regulation that reinforce smoking and hamper smoking cessation efforts.

Social imitation of alcohol consumption and ingratiation motives in young adults

Across 2 studies we tested the hypothesis that social ingratiation motives may be an important factor explaining social imitation of alcohol consumption. In Study 1, participants drank alcohol with a heavy versus light drinking confederate under conditions that were designed to heighten or reduce (participants believed they would not be judged) motivation for ingratiation. In Study 2 we manipulated the degree to which participants believed they had already successfully ingratiated themselves with a heavy or no (alcohol) drinking confederate. In Study 1, participants' alcohol consumption was most strongly influenced by the confederate's drinking behavior when they believed that they would later be judged by the confederate. In Study 2, participants' alcohol consumption was influenced by the confederate's drinking behavior and this effect was particularly pronounced if participants were unsure if the confederate had accepted them. The desire for social ingratiation may in part explain why people imitate the drinking behavior of those around them. (PsycINFO Database Record

The interaction between the dopamine receptor D4 (DRD4) variable number tandem repeat polymorphism and perceived peer drinking norms in adolescent alcohol use and misuse

Peer drinking norms are arguably one of the strongest correlates of adolescent drinking. Prospective studies indicate that adolescents tend to select peers based on drinking (peer selection) and their peers' drinking is associated with changes in adolescent drinking over time (peer socialization). The present study investigated whether the peer selection and socialization processes in adolescent drinking differed as a function of the dopamine receptor D4 (DRD4) variable number tandem repeat genotype in two independent prospective data sets. The first sample was 174 high school students drawn from a two-wave 6-month prospective study. The second sample was 237 college students drawn from a three-wave annual prospective study. Multigroup cross-lagged panel analyses of the high school student sample indicated stronger socialization via peer drinking norms among carriers, whereas analyses of the college student sample indicated stronger drinking-based peer selection in the junior year among carriers, compared to noncarriers. Although replication and meta-analytic synthesis are needed, these findings suggest that in part genetically determined peer selection (carriers of the DRD4 seven-repeat allele tend to associate with peers who have more favorable attitudes toward drinking and greater alcohol use) and peer socialization (carriers' subsequent drinking behaviors are more strongly associated with their peer drinking norms) may differ across adolescent developmental stages.

The effects of alcohol on emotion in social drinkers

Understanding why people drink alcohol and in some cases develop drinking problems has long puzzled researchers, clinicians, and patients alike. In the mid-1940s and early 1950s, experimental research began to systematically investigate alcohol's hedonic properties. Presumably, alcohol consumption would prove reinforcing as a consequence of its capacity either to relieve stress or to brighten positive emotional experiences. This article reviews experimental research through the years examining the impact of alcohol on both the relief of negative affect and the enhancement of positive affect. It covers initial accounts that emphasized direct pharmacological effects of ethanol on the central nervous system. These early studies offered surprisingly tepid support for the premise that alcohol improved emotional states. Next, studies conducted in the 1970s are considered. Informed by social learning theory and employing advances derived from experimental psychology, this research sought to better understand the complex effects of alcohol on emotion. Coverage of this work is followed by discussion of current formulations, which integrate biological and behavioral approaches with the study of cognitive, affective, and social processes. These current perspectives provide insight into the particular conditions under which alcohol can boost emotional experiences. Finally, future research directions and clinical implications are considered.

Extraversion and the Rewarding Effects of Alcohol in a Social Context

The personality trait of extraversion has been linked to problematic drinking patterns. Researchers have long hypothesized that such associations are attributable to increased alcohol-reward sensitivity among extraverted individuals, and surveys suggest that individuals high in extraversion gain greater mood enhancement from alcohol than those low in extraversion. Surprisingly, however, alcohol administration studies have not found individuals high in extraversion to experience enhanced mood following alcohol consumption. Of note, prior studies have examined extraverted participants-individuals who self-identify as being highly social-consuming alcohol in isolation. In the present research, we used a group drinking paradigm to examine whether individuals high in extraversion gained greater reward from alcohol than did those low in extraversion and, further, whether a particular social mechanism (partners’ Duchenne smiling) might underlie alcohol reward sensitivity among extraverted individuals. Social drinkers (n 720) consumed a moderate dose of alcohol, placebo, or control beverage in groups of 3 over the course of 36 min. This social interaction was video-recorded, and Duchenne smiling was coded using the Facial Action Coding System. Results indicated that participants high in extraversion reported significantly more mood enhancement from alcohol than did those low in extraversion. Further, mediated moderation analyses focusing on Duchenne smiling of group members indicated that social processes fully and uniquely accounted for alcohol reward-sensitivity among individuals high in extraversion. Results provide initial experimental evidence that individuals high in extraversion experience increased mood-enhancement from alcohol and further highlight the importance of considering social processes in the etiology of alcohol use disorder.

Serotonin and Dopamine Gene Variation and Theory of Mind Decoding Accuracy in Major Depression: A Preliminary Investigation

Theory of mind–the ability to decode and reason about others’ mental states–is a universal human skill and forms the basis of social cognition. Theory of mind accuracy is impaired in clinical conditions evidencing social impairment, including major depressive disorder. The current study is a preliminary investigation of the association of polymorphisms of the serotonin transporter (SLC6A4), dopamine transporter (DAT1), dopamine receptor D4 (DRD4), and catechol-O-methyl transferase (COMT) genes with theory of mind decoding in a sample of adults with major depression. Ninety-six young adults (38 depressed, 58 non-depressed) completed the ‘Reading the Mind in the Eyes task’ and a non-mentalistic control task. Genetic associations were only found for the depressed group. Specifically, superior accuracy in decoding mental states of a positive valence was seen in those homozygous for the long allele of the serotonin transporter gene, 9-allele carriers of DAT1, and long-allele carriers of DRD4. In contrast, superior accuracy in decoding mental states of a negative valence was seen in short-allele carriers of the serotonin transporter gene and 10/10 homozygotes of DAT1. Results are discussed in terms of their implications for integrating social cognitive and neurobiological models of etiology in major depression.

The Role of Craving in Substance Use Disorders: Theoretical and Methodological Issues

Craving is a central feature of addiction. Its recent inclusion as a diagnostic criterion for substance use disorders in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders appears at a time when craving research is at an all-time high. Craving is thought to predict relapse and may deter individuals from even trying to quit. Researchers have developed experimental craving-induction paradigms to identify factors contributing to craving and to test interventions to alleviate craving. This review offers a critique of laboratory craving studies, with particular emphasis on cigarette craving. It raises questions concerning several conceptual and methodological assumptions underlying this research, identifies processes that may explain why cravings are linked to drug use and relapse, addresses contextual factors that may influence various experiences of craving, and considers recent interventions targeting craving. The relation between craving and both emotion and coping is discussed, as well as the level of insight that individuals have about their own future cravings.

Differential Susceptibility: The Genetic Moderation of Peer Pressure on Alcohol Use

Although peer pressure can influence adolescents' alcohol use, individual susceptibility to these pressures varies across individuals. The dopamine receptor D4 gene (DRD4) is a potential candidate gene that may influence adolescents' susceptibility to their peer environment due to the role dopamine plays in reward sensation during social interaction. We hypothesized that DRD4 genotype status would moderate the impact of 7th-grade antisocial peer pressure on 12th-grade lifetime alcohol use (n = 414; 58.7% female; 92.8% White). The results revealed significant main effects for antisocial peer pressure, but no main effects for DRD4 genotype on lifetime alcohol use. Adolescent DRD4 genotype moderated the association between peer pressure and lifetime alcohol use. For individuals who carried at least one copy of the DRD4 7-repeat allele (7+), antisocial peer pressure was associated with increased lifetime alcohol use. These findings indicate that genetic sensitivity to peer pressure confers increased alcohol use in late adolescence.

Associations Between a Dopamine D4 Receptor Gene, Alcohol Use, and Sexual Behaviors among Female Adolescent African Americans

Adolescent African-American females are disproportionately impacted by HIV, thus there is a clear need to understand factors associated with increased HIV-risk behaviors among this vulnerable population. We sought to explore the association between a dopamine D4 receptor gene (DRD4), a genetic marker associated with natural variations in rewarding behaviors, and self-reported alcohol-use and sexual risk-behaviors, while controlling for other known correlates of risk-taking such as impulsivity, sensation seeking, and peer norms among a group of high-risk African American female adolescents to evaluate whether this biological factor enhances our understanding of patterns of risk in this vulnerable group.

The effect of dopamine D4 receptor density on novelty seeking, activity, social interaction, and alcohol binge drinking in adult mice

The dopamine D4 receptor has been postulated to play a role in the pathophysiology of alcoholism. This study examined how varying levels of D4 expression and their associated behaviors in male and female mice correlate with future alcohol intake. We hypothesized that: (1) mice with low (Drd4(+/-) ) or deficient (Drd4(-/-) ) in D4 receptors would show enhanced ethanol consumption compared with control mice (Drd4(+/+) ), and (2) a specific phenotype in these mice is associated with future vulnerability for alcohol consumption. Individually housed mice were allowed free access to ethanol (20% vv) in the dark (DID). The behaviors measured in male and female mice were: novel object recognition, open-field locomotor activity, and social interaction. Correlation analyses showed that in male Drd4(-/-) mice (relative to Drd4(+/+) controls), anxiolytic behavior was significantly correlated with increased alcohol consumption. Also, in male Drd4(-/-) mice, there was a significant positive correlation between increased exploratory behavior and increased alcohol consumption. These findings were not observed in females. In conclusion, our data suggest that the dopamine D4 receptor gene has an important role in increased exploratory and anxiolytic behavior only in males and these behaviors were positively correlated with increased alcohol consumption. This interaction between sex hormones and dopamine D4 receptor genotype/function predicting future alcohol abuse and correlation with anxiolytic and exploratory behavior in male mice could have important implications for better understanding of vulnerabilities associated with addiction.

Looking Forward in Candidate Gene Research: Concerns and Suggestions

Candidate Gene × Environment (cGxE) interaction research holds promise for helping us understand for whom and why environments matter for families and development. In their commentary on our target article (G. L. Schlomer, G. M. Fosco, H. H. Cleveland, D. J. Vandenbergh, & M. E. Feinberg, 2015), J. E. Salvatore and D. M. Dick (2015) present their view of the current state and future of cGxE research and frame the debate regarding its merits for advancing knowledge of gene-environment interplay. In this reply, we discuss points of agreement and departure and provide a list of 5 domains by which the quality of cGxE research should be evaluated. Our hope is that researchers will use this list as a guide for their own work.

The conditioning of intervention effects on early adolescent alcohol use by maternal involvement and dopamine receptor D4 (DRD4) and serotonin transporter linked polymorphic region (5-HTTLPR) genetic variants

Data drawn from the in-home subsample of the PROSPER intervention dissemination trial were used to investigate the moderation of intervention effects on underage alcohol use by maternal involvement and candidate genes. The primary gene examined was dopamine receptor D4 (DRD4). Variation in this gene and maternal involvement were hypothesized to moderate the influence of intervention status on alcohol use. The PROSPER data used were drawn from 28 communities randomly assigned to intervention or comparison conditions. Participating youth were assessed in five in-home interviews from sixth to ninth grades. A main effect of sixth-grade pretest maternal involvement on ninth-grade alcohol use was found. Neither intervention status nor DRD4 variation was unconditionally linked to ninth-grade drinking. However, moderation analyses revealed a significant three-way interaction among DRD4 status, maternal involvement, and intervention condition. Follow-up analyses revealed that prevention reduced drinking risk, but only for youth with at least one DRD4 seven-repeat allele who reported average or greater pretest levels of maternal involvement. To determine if this conditional pattern was limited to the DRD4 gene, we repeated analyses using the serotonin transporter linked polymorphic region site near the serotonin transporter gene. The results for this supplemental analysis revealed a significant three-way interaction similar but not identical to that found for DRD4.

DRD4 and susceptibility to peer influence on alcohol use from adolescence to adulthood

BACKGROUND

The long allele of DRD4 is associated with greater susceptibility to peer influences on alcohol use in young adulthood, but it is unclear whether this increased susceptibility extends to other developmental periods. This study examined the interactive effects of DRD4 polymorphism and friends' alcohol use from adolescence to adulthood.

METHODS

Participants (N = 340; 59% female; 98% White) reported on their own and their friends' alcohol use at four time points between mean ages 17 and 33. Autoregressive cross-lagged models evaluated reciprocal relationships between friends' alcohol use and participants' own alcohol use and frequency of heavy drinking over time. Multigroup modeling tested differences in model paths and covariances across high vs. low risk DRD4 polymorphisms.

RESULTS

Alcohol use at age 33 was predicted by previous friends' alcohol use and correlated with current friends' alcohol use only for carriers of the DRD4 long allele. Regardless of DRD4 genotype, friends' alcohol use at age 17 predicted greater alcohol use and more frequent heavy drinking at age 23. Alcohol use and/or heavy drinking predicted greater friends' alcohol use at later time points for both genotype groups across adolescence and adulthood.

CONCLUSIONS

The long allele of DRD4 is associated with increased susceptibility to peer influences on alcohol use in young adulthood, but not earlier in development. Adults with the long allele of DRD4 may benefit from interventions educating them about this risk and equipping them with strategies to reduce affiliations with and influence of drinking friends.

A social-attributional analysis of alcohol response

Conventional wisdom and survey data indicate that alcohol is a social lubricant and is consumed for its social effects. In contrast, the experimental literature examining alcohol's effects within a social context reveals that alcohol does not consistently enhance social-emotional experience. We identify a methodological factor that might explain inconsistent alcohol-administration findings, distinguishing between studies featuring unscripted interactions among naïve participants (k = 18) and those featuring scripted social interactions with individuals identified as study confederates (k = 18). While 89% of naïve-participant studies find positive effects of alcohol on mood (d = 0.5), only 11% of confederate studies find evidence of significant alcohol-related mood enhancement (d = -0.01). The naïve-participant versus confederate distinction remains robust after controlling for various moderators including stress manipulations, gender, group size, anxiety outcome measure, and within-group consistency of beverage assignment. Based on the findings of our review, we propose a multidimensional, social-attributional framework for understanding alcohol-related reward. Borrowing organizing principles from attribution theory, the social-attributional approach predicts that alcohol will enhance mood when negative outcomes are perceived to be unstable and/or self-relevant. Our framework proposes that alcohol's effects within a social context are largely explained by its tendency to free individuals from preoccupation with social rejection, allowing them to access social rewards. The social-attributional approach represents a novel framework for integrating distinct, well-validated concepts derived from several theories of alcohol's effects. It further presents promising lines of inquiry for future research examining the role of social factors in alcohol reward and addiction susceptibility.

Solitary Alcohol Use in Teens Is Associated With Drinking in Response to Negative Affect and Predicts Alcohol Problems in Young Adulthood

Adolescent solitary drinking may represent an informative divergence from normative behavior, with important implications for understanding risk for alcohol-use disorders later in life. Within a self-medication framework, we hypothesized that solitary alcohol use would be associated with drinking in response to negative affect and that such a pattern of drinking would predict alcohol problems in young adulthood. We tested these predictions in a longitudinal study in which we examined whether solitary drinking in adolescence (ages 12-18) predicted alcohol-use disorders in young adulthood (age 25) in 466 alcohol-using teens recruited from clinical programs and 243 alcohol-using teens recruited from the community. Findings showed that solitary drinking was associated with drinking in response to negative affect during adolescence and predicted alcohol problems in young adulthood. Results indicate that drinking alone is an important type of alcohol-use behavior that increases risk for the escalation of alcohol use and the development of alcohol problems.

Association between the seven-repeat allele of the dopamine-4 receptor gene (DRD4) and spontaneous food intake in pre-school children

BACKGROUND

Studies in adults show associations between the hypofunctional seven-repeat allele (7R) of the dopamine-4 receptor gene (DRD4), increased eating behaviour and/or obesity, particularly in females. We examined whether 7R is associated with total caloric intake and/or food choices in pre-schoolers.

METHODS

150 four-year-old children taking part in a birth cohort study in Canada were administered a snack test meal in a laboratory setting. Mothers also filled out a food frequency questionnaire to address childrens' habitual food consumption. Total caloric and individual macronutrient intakes during the snack meal and specific types of foods as reported in the food diaries were compared across 7R allele carriers vs. non-carriers, using current BMI as a co-variate.

RESULTS

We found significant sex by genotype interactions for fat and protein intake during the snack test. Post hoc testing revealed that in girls, but not boys, 7R carriers ate more fat and protein than did non-carriers. Based on the food diaries, across both sexes, 7R carriers consumed more portions of ice cream and less vegetables, eggs, nuts and whole bread, suggesting a less healthy pattern of habitual food consumption.

CONCLUSION

The 7R allele of DRD4 influences macronutrient intakes and specific food choices as early as four years of age. The specific pattern of results further suggests that prior associations between the 7R allele and adult overeating/obesity may originate in food choices observable in the preschool years. Longitudinal follow-up of these children will help establish the relevance of these findings for obesity risk and prevention.

Genotype×age interaction in human transcriptional ageing

Individual differences in biological ageing (i.e., the rate of physiological response to the passage of time) may be due in part to genotype-specific variation in gene action. However, the sources of heritable variation in human age-related gene expression profiles are largely unknown. We have profiled genome-wide expression in peripheral blood mononuclear cells from 1240 individuals in large families and found 4472 human autosomal transcripts, representing ~4349 genes, significantly correlated with age. We identified 623 transcripts that show genotype by age interaction in addition to a main effect of age, defining a large set of novel candidates for characterization of the mechanisms of differential biological ageing. We applied a novel SNP genotype × age interaction test to one of these candidates, the ubiquilin-like gene UBQLNL, and found evidence of joint cis-association and genotype by age interaction as well as trans-genotype by age interaction for UBQLNL expression. Both UBQLNL expression levels at recruitment and cis genotype are associated with longitudinal cancer risk in our study cohort.