Structural and Functional Neuroimaging Predictors of Substance Use-Related Outcomes Across Alcohol, Tobacco, and Cannabis
Year: 2026
Type: dissertation
Abstract: Substance use disorders (SUDs) involving alcohol, tobacco, and cannabis are prevalent, heterogeneous conditions characterized by disruptions in reward processing, salience attribution, and executive control. Identifying neurobiological markers associated with intervention response and disorder severity may advance precision-oriented approaches to prevention and treatment. This dissertation used magnetic resonance imaging (MRI) to examine structural and functional neural correlates of substance use trajectories across alcohol, tobacco, and cannabis. Across the three studies, consistent involvement of frontal regulatory systems emerged. Chapter Two investigated cortical morphometric predictors of response to a brief motivational interviewing intervention among adults with alcohol use disorder. Greater cortical thickness within frontal regions was associated with greater reductions in alcohol consumption, suggesting that structural integrity within executive systems may facilitate behavioural change. Chapter Three systematically reviewed MRI predictors of smoking cessation outcomes, identifying consistent involvement of medial prefrontal cortex (mPFC), anterior cingulate cortex (ACC), insula, and striatal regions. Successful cessation was associated with greater frontal gray matter volume, reduced cue reactivity, and stronger connectivity within regulatory networks. Finally, Chapter Four examined high-resolution orbitofrontal cortex and mPFC/ACC morphometry in emerging adults at elevated risk for cannabis use disorder, demonstrating associations between structural variations and greater symptom severity. Collectively, these findings support a transdiagnostic framework in which variation within distributed frontal regulatory circuitry relates to both vulnerability and intervention responsiveness across substances. By integrating structural morphometry, functional neuroimaging synthesis, community-based samples, and clinically meaningful outcomes, this dissertation advances understanding of brain-behaviour relationships in SUDs and provides a foundation for future longitudinal and precision-oriented neuroimaging research.
Source: MacSphere (McMaster University)
DOI: 10.71548/10203
Author: Hargreaves, Tegan Lee
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7199532671