Hollis Karoly
Research Affiliate • Assistant Professor
Colorado State University Department of Psychology

Affiliated Research with ICS

I am currently working in collaboration with Dr. Cinnamon Bidwell on my NIAAA-funded K23 award focused on alcohol and cannabis co-use and effects on the brain and body, specifically along the microbiota-gut-brain axis. I am also involved in numerous ongoing collaborations with Dr. Bidwell's group, involving data analysis and manuscript preparation for a number of her current NIH-funded projects. 

Bio and Research Interests

Broadly, my research aims to characterize neural, molecular and behavioral mechanisms underlying the etiology of alcohol use disorders, in an effort to inform treatment development. More specifically, I am interested in how functional impairments along the microbiota-gut-brain-axis (MGBA; which refers to bidirectional interactions between gut microbes, endocrine, autonomic, enteric, immune and central nervous systems) may promote alcohol use behavior and serve as potential treatment targets. In recent years, my work has increasingly emphasized the role of the endogenous cannabinoid system - which is distributed heavily throughout the brain and gut - in the context of alcohol use disorders.

Thus, I am conducting several studies measuring the impact of phytocannabinoids (primarily cannabidiol [CBD] and tetrahydrocannabinol [THC]) on behavioral phenotypes related to alcohol use disorder (alcohol consumption, craving, intoxication) and on biomarkers across the MGBA (brain structure and function, peripheral inflammation, intestinal permeability, gut microbial composition).

To this end, I combine behavioral measures, molecular biology methods, neuroimaging and high throughput 16S ribosomal RNA gene sequencing to explore the impact of alcohol and cannabis on the MGBA and behavior. Because this work involves acute administration of various cannabis products, my research also makes use of a Mobile Drug Administration Laboratory which adheres to federal guidelines restricting cannabis administration in academic research.