Gene-environment interaction in alcohol problems in emerging and young adulthood : the DRD4 VNTR, DAT1 VNTR, and 5-HTTLPR polymorphisms

Title from PDF of title page (University of Missouri--Columbia, viewed on September 17, 2010).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisor: Dr. Kenneth J. Sher.Vita.Ph. D. University of Missouri--Columbia 2009.Alcohol problems at different developmental stages are associated with different genetic and environmental factors. Taking a developmentally sensitive approach, the current study characterized interaction effects between monoamine gene polymorphisms and developmental environments on alcohol problems during emerging and young adulthood. Prospective data of a cohort of 454 Caucasian individuals assessed at the mean ages of 18 to 34 were used. A longitudinal hierarchical factor model was used to model one persistent alcohol problem factor throughout emerging and young adulthood and two residual alcohol problem factors limited to emerging adulthood and to young adulthood. Then, interaction effects between each of the DRD4 VNTR, DAT1 VNTR, and 5-HTTLPR genes and three developmental environments were modeled to account for those alcohol problem factors. Persistence of those environments was modeled as an enduring effect of childhood adversity on the persistent alcohol problem factor and situational effects of college involvement and delayed adult role transition on the two developmentally limited alcohol problem factors. Carriers of the DRD4 long allele showed greater persistent alcohol problems as childhood adversity increased and greater alcohol problems limited to emerging adulthood as college involvement increased. Alcohol problems among non-carriers of the long allele, however, did not differ as a function of childhood adversity and college involvement. For the DAT1 VNTR and the 5-HTTLPR polymorphisms, no significant gene-environment interaction was found. Although preliminary, these findings highlight the importance of modeling both distal and proximal environments and their interplay with genetic susceptibility in alcohol problems at specific developmental stages.Includes bibliographical reference

Selection and socialization effects of Greek affiliation on heavy drinking across the transition to college and into the college years: the effects of personality traits and drinking norms

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file viewed on (February 21, 2007)Includes bibliographical references.Thesis (M.A.) University of Missouri-Columbia 2006.Dissertations, Academic -- University of Missouri--Columbia -- Psychology.Although heavy drinking among fraternity and sorority members is well documented, it is less clear whether the Greek environment facilitates heavy drinking or whether heavy drinkers select into Greek environments. Moreover, mechanisms underlying the relation between Greek environment and drinking rarely have been studied. Selection and socialization effects of Greek affiliation on drinking and the effects of personality traits and peer drinking norms on those associations were investigated using longitudinal data throughout the transition to college (N = 2,376). Latent growth models supported both selection and socialization effects; individuals who involved in heavier drinking at precollege were more likely to join Greek organizations and in turn Greek members increased heavy drinking more than nonmembers, even after the selection effect was controlled. Extraversion was associated with Greek affiliation independent of precollege drinking, whereas the effect of novelty seeking on Greek affiliation was partially mediated by heavier precollege drinking. Peer drinking norms mediated the effect of Greek affiliation on drinking only during the first semester of college. These selection and socialization processes were largely invariant across gender.Theoretical and clinical implications are discussed

Pathways of Perceptual Primacy: ERP Evidence for Relationships Between Autism Traits and Enhanced Perceptual Functioning

Autistic individuals show enhanced perceptual functioning on many behavioral tasks. Neurophysiological evidence also supports the conclusion that autistic individuals utilize perceptual processes to a greater extent than neurotypical comparisons to support problem solving and reasoning; however, how atypicalities in early perceptual processing influence subsequent cognitive processes remains to be elucidated. The goals of the present study were to test the relationship between early perceptual and subsequent cognitive event related potentials (ERPs) and their relationship to levels of autism traits. 62 neurotypical adults completed the Autism Spectrum Quotient (AQ) and participated in an ERP task. Path models were compared to test causal relationships among an early perceptual ERP (the P1 component), a subsequent cognitive ERP (the N400 effect), and the Attention to Detail subscale of the AQ. The size of participants’ P1 components was positively correlated with the size of their N400 effect and their Attention to Detail score. Model comparisons supported the model specifying that variation in Attention to Detail scores predicted meaningful differences in participants’ ERP waveforms. The relationship between Attention to Detail scores and the size of the N400 effect was significantly mediated by the size of the P1 effect. This study revealed that neurotypical adults with higher levels of Attention to Detail show larger P1 differences, which, in turn, correspond to larger N400 effects. Findings support the Enhanced Perceptual Functioning model of autism, suggesting that early perceptual processing differences may cascade forward and result in modifications to later cognitive mechanisms

DRINKING MOTIVES AS MEDIATORS IN THE RELATION BETWEEN PERSONALITY DISORDER SYMPTOMS AND ALCOHOL USE DISORDER

Research shows high comorbidity between Cluster B Personality Disorders (PDs) and Alcohol Use Disorders (AUDs). Studies of personality traits and alcohol use have identified coping and enhancement drinking motives as mediators of the relation among impulsivity, negative affectivity or affectivity instability, and alcohol use. To the extent that certain PDs reflect extreme expression of these traits, drinking motives were hypothesized to mediate the relation between PD symptoms and presence/absence of an alcohol use disorder (AUD). This hypothesis was tested using a series of cross-sectional and prospective path models estimating the extent that coping and enhancement drinking motives mediated the relation between cluster A, B, and C PD symptom counts and AUD diagnosis among a sample of 168 young adults between ages 18 and 21. Enhancement motives mediated the cross-sectional relation between Cluster B symptoms and AUD. Prospectively, enhancement motives partially mediated the relation between Cluster B personality symptoms and AUD through the stability of Year 1 AUD to Year 3 AUD. Results suggest that enhancement motives may be especially important in understanding the relation between Cluster B personality disorders and AUDs

Personality disorder symptoms, drinking motives, and alcohol use and consequences: cross-sectional and prospective mediation

Research shows high comorbidity between Cluster B personality disorders (PDs) and alcohol use disorders (AUDs). Studies on personality traits and alcohol use have identified coping and enhancement drinking motives as mediators in the relations among impulsivity, affective instability, and alcohol use. To the extent that PDs reflect extreme expression of these traits, drinking motives should mediate the relation between PD symptoms and alcohol involvement. This was tested using path models estimating the extent to which coping and enhancement drinking motives mediated the relation between Cluster B symptom counts and alcohol use and problems both concurrently and at a 5-year follow-up. Three hundred fifty-two adults participated in a multiwave study of risk for alcoholism (average age = 29 years at Wave 1). Enhancement motives mediated (a) the cross-sectional relation between Cluster B symptoms and drinking quantity/frequency, heavy drinking, total drinking consequences, dependence features, and AUD diagnosis and (b) the prospective relation to AUDs. Although coping motives mediated the relation between Cluster B symptoms and drinking consequences and dependence features cross-sectionally, prospective effects were limited to indirect effects through Time 1