Functional & Structural Connectivity in Alcohol Use Disorder

National Institute On Alcohol Abuse And Alcoholism

Investigators

Linked publications & trials

Abstract

1. Functional Connectivity a. PAG functional connectivity - The Periaqueductal gray (PAG) is a region widely implicated in pain, depression, negative emotionality, and sleep studies, most of which are also comorbidities associated with substance use disorders (SUD) (Le, et al. 2020; George, et al. 2019). Despite the apparent prominent involvement of PAG in behavioral psychiatric disorders there have been limited neuroimaging studies investigating the modulatory role that this region plays in SUD maintenance of and relapse. In collaboration with Dr. Spagnolo, we are currently studying the association between AUD and functional PAG connectivity. b. TTL and functional connectivity - Timing and type of trauma have been shown to impact on the development, function and connectivity of brain circuits implicated in emotion processing, top-down inhibitory control, and cognitive functions. Dysfunctions in these processes and their underlying brain circuits are commonly observed in patients with alcohol use disorder (AUD). Furthermore, the high comorbidity between AUD and PTSD suggests that trauma exposure during adulthood also plays a critical role in increasing the risk and severity of AUD. Building on this body of evidence, the goal of this study is to investigate whether timing of trauma (childhood vs. adulthood) differentially affects the behavioral and circuit-level phenotype of individuals with AUD. We have obtained the necessary clinical and imaging data and are in the process of establishing our analysis to advance this study. 2. Structural Connectivity Sex and age association with AUD - The damage associated with chronic alcohol use on the brain's white matter has been demonstrated by previous diffusion tensor imaging (DTI) research. However, there is conflicting evidence as to whether the severity of damage is influenced by an individual's biological sex. The purpose of the present study was to investigate the prevalence of sex differences in the white matter microstructure of the brains of individuals with alcohol use disorder (AUD) and healthy controls. One hundred participants with AUD (38 female, ages 21-68) partaking in the NIAAA inpatient treatment program and 98 healthy control participants (52 female, ages 21-65) underwent a diffusion weighted scan. Images collected were processed for each subject individually and voxelwise tract-based spatial statistics (TBSS) analysis was conducted to measure differences in the DTI measures of fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) between groups. Our analyses testing for differences in group and sex revealed widespread differences between subjects with AUD and control subjects, but no interaction between group and sex. Our exploration of other variables such as demographic and alcohol use factors revealed significant impacts of age on white matter microstructure that were more pronounced in those with AUD. These results bolster recent findings of similar alcohol-related microstructural damage in men and women with AUD but indicates the importance of considering age in these studies.