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Background: Systemic oppression, particularly towards sexual minorities, continues to be deeply rooted in the bedrock of many societies globally. Experiences with minority stressors (e.g. discrimination, hate-crimes, internalized homonegativity, rejection sensitivity, and microaggressions or everyday indignities) have been consistently linked to adverse mental health outcomes. Elucidating the neural adaptations associated with minority stress exposure will be critical for furthering our understanding of how sexual minorities become disproportionately affected by mental health burdens. Following PRISMA-guidelines, we systematically reviewed published neuroimaging studies that compared neural dynamics among sexual minority and heterosexual populations, aggregating information pertaining to any measurement of minority stress and relevant clinical phenomena. Results: Only 1 of 13 studies eligible for inclusion examined minority stress directly, where all other studies focused on investigating the neurobiological basis of sexual orientation. In our narrative synthesis, we highlight important themes that suggest minority stress exposure may be associated with decreased activation and functional connectivity within the default-mode network (related to the sense-of-self and social cognition), and summarize preliminary evidence related to aberrant neural dynamics within the salience network (involved in threat detection and fear processing) and the central executive network (involved in executive functioning and emotion regulation). Importantly, this parallels neural adaptations commonly observed among individuals with posttraumatic stress disorder (PTSD) in the aftermath of trauma and supports the inclusion of insidious forms of trauma related to minority stress within models of PTSD. Conclusions: Taken together, minority stress may have several shared neuropsychological pathways with PTSD and stress-related disorders. Here, we outline a detailed research agenda that provides an overview of literature linking sexual minority stress to PTSD and insidious trauma, moral affect (including shame and guilt), and mental health risk/resiliency, in addition to racial, ethnic, and gender related minority stress. Finally, we propose a novel minority mosaic framework designed to inform future directions of minority stress neuroimaging research from an intersectional lens.

The purpose of the present dissertation was to shed light on the neurophysiological effect of regular consumption of low amounts of alcohol on two important aspects of executive functions, cognitive interference and response inhibition, using functional magnetic resonance imaging (fMRI) in a sample of young adults. Participants were recruited from the Ottawa Prenatal Prospective Study (OPPS), a longitudinal study that has collected data from participants from infancy to young adulthood, which permitted control of a number of potentially confounding drug and lifestyle variables. This allowed for investigation of the unique effect of alcohol use on executive functions. The dissertation itself is comprised of two original manuscripts: the first study compared low-level alcohol users to controls on performance of the Counting Stroop, a task of cognitive interference; and the second study compared users to controls on performance of the Go/No-Go, a task of response inhibition.Although the results of both studies found no performance differences between groups, low-level alcohol users had significantly more brain activation in several regions, including areas not typically associated with task processing, compared to irregular or non-drinker controls. This difference in neurophysiology may be reflective of compensatory strategies within the brain, whereby the recruitment of additional regions may be attempting to compensate for potential underlying deficits that occur with increasing cognitive demand. While further research is needed to validate this hypothesis, the present findings highlight the vulnerability of the developing brain.