Lab Director

Hollis Karoly, Ph.D. (she/her)

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). Outside of work, I try to spend as much time as I can enjoying the Colorado mountains with my husband and son.

Graduate students

Meggan Drennan, M.S. (she/her)

I am a Ph.D. candidate in the Cognitive Neuroscience program and currently conducting my dissertation research through heading the ORCA study. Prior to arriving at CSU, I received my B.S. in Behavioral Neuroscience from St. Edward’s University in Austin, Tx where I discovered my love of research and decided to pursue a career in exploring the physiological mechanisms behind psychology and behavior. I relocated to Fort Collins and completed my Master’s degree in Biomedical Sciences before joining the ENIGMA lab for my Ph.D. My research combines psychological and biological measures to investigate relationships between the gut microbiome, brain and behavior as it is influenced by alcohol and cannabis use. Outside of academia, I am the mother of 2 beautiful children and enjoy writing music, playing the piano and singing, as well as creating artwork in multiple forms.


Cianna Piercey, M.A. (she/they)

I am a second-year student in the Counseling Psychology Ph.D. program and currently conducting my thesis research through heading the DISCO study. Prior to beginning my graduate studies at CSU, I completed my B.S. in clinical psychology and neuroscience at the University of Central Florida. Broadly, I am interested in researching biopsychosocial mechanisms of substance use risk mitigation, with a focus on protective behavioral strategies (PBS). In my current work, I am conducting a field study of polysubstance use patterns and PBS (e.g., test drugs for the presence of fentanyl) among festival and concert attendees in Colorado. Ultimately, I am passionate about reducing stigma and treating people who use drugs with the compassion and respect that they deserve! In my free time, I enjoy painting, hiking, seeing live music, and spending time with my partner and our sweet puppy, Macaroni.


Vanessa Stallsmith, M.A. (she/her)

I am a second-year student in the Counseling Psychology Ph.D. program and the lead graduate researcher on the FRACTAL and EXCEL studies. I moved to Colorado in 2016 to complete my dual B.A. in Neuroscience and Psychology at the University of Colorado, Boulder (sko buffs!). I am interested in researching novel therapeutic approaches to alleviate mental health disorders and promote overall wellness. I am fascinated by the intersection of behavioral health and physical well-being and aspire to someday work in a primary care facility or academic medical center where I can incorporate exercise, diet, and counseling in my approach to “whole-person” care. When I’m not working, I love to celebrate my body through movement. As such, I’m typically at the gym or on a hike with my partner. I love being outdoors and exploring this beautiful state! I’m also a self-proclaimed foodie and enjoy trying new recipes and feeding the people I love.


Eleftherios (Lefty) Hetelekides, M.S. (he/him)

I started the Counseling Psychology Ph.D. program in Fall 2022 and am currently the lead graduate researcher on the NECCTAR study. My previous research experiences include preclinical work related to the endocannabinoid system, neuroimaging, and neuropharmacology in mouse and rat models of addiction. I have also been involved in clinically focused substance use research related to personality, protective behavioral strategies/harm reduction, drug-related behaviors, craving, and neuroelectrophysiology (i.e., EEG). For my PhD and career, I am interested in exploring biopsychosocial mechanisms related to psychopathology, substance use/addiction, and behavior change. In my free time I enjoy being outside, exercising (especially rock climbing!), chilling with friends, having philosophical discussions, playing video games, and cooking delicious food with minimal effort in my air fryer.

Claire Prince (she/her)

I am a first-year student in the Counseling Psychology Ph.D. program and a lead graduate researcher on the NECCTAR study. Before coming to CSU, I received my B.A. in Neuroscience from the University of Pennsylvania in 2021 and subsequently completed a 2-year postbaccalaureate research training program at the National Institute on Drug Abuse in Baltimore. My research background is predominantly preclinical, with a focus on developing novel pharmacotherapeutics for alcohol use disorder, and I am interested in studying substance use and co-occurring disorders from a biopsychosocial and harm reduction-aligned perspective. Currently, I am working on projects exploring the relationship between alcohol/cannabis use and disordered eating behaviors. In my free time, I enjoy baking/cooking, roller skating, singing, and hiking.

John (JD) Curtis (he/him)

I am a first-year student in the Counseling Psychology Ph.D. Program here at CSU. I graduated from Arizona State University with a B.S. in psychology. My research interests are in comorbid substance misuse & trauma, harm reduction, therapeutic potentials of psychedelics & cannabis, and in health & treatment disparities among Veteran & LGBT populations. In my free time I enjoy pursuing volunteer experiences in harm reduction or community service spaces. Additionally, I enjoy meditational experiences, live music, and can almost always otherwise be found in a hammock with a good book.

lab manager

Jesse Ruehrmund (she/her)

My name is Jesse “Roo” Ruehrmund, I graduated from Colorado State University in the College of Liberal Arts and College of Veterinary and Biomedical Sciences in 2023 and soon after took on the role of lab manager for the ENIGMA lab. I hope to gain a few years of field experience before continuing on to a PhD/MD program to pursue a career in the field of neuro-psychopharmacology. I look forward to seeing how research continues to expand to explore more novel drug interactions and therapies. I hope in my future to see and participate in a new holistic approach to therapies where all facets of a person’s life can be cared for by a team that works together to provide a thorough but fluid and efficient treatment process. Outside of research I enjoy spending my time outside on the water or exploring Colorado’s social scene with my friends.

Research Assistants

Tabitha McMichael (she/her)

I am an undergraduate student in the college of natural sciences majoring in Psychology and minoring in Chemistry. After taking classes on physiology and learning how the brain interacts with different chemical compounds, I became interested in how different drugs affect the mind, brain, and behavior of the individual. I am currently concentrating in addictions counseling to advance my knowledge on addictions and their treatment. Working with Dr. Karoly and the ENIGMA lab has allowed me to further pursue interests in potential addiction treatments and learning how different drug combinations alter physical and psychological factors. Outside of CSU I work as a Certified Phlebotomy Technician at the Medical Center of the Rockies and volunteer as a crisis counselor with Crisis Textline, and in my free time I recently became a plant mom and love traveling and crocheting. 


Kenyon Perkins (she/her)

I am a fourth-year student at CSU majoring in neuroscience, with a cognitive and behavioral concentration. My research interests include investigating how environmental factors such as stress and drugs can impact gene expression which facilitates neurological and behavioral changes, such as in substance use and mood disorders. Besides epigenetics, I’m very interesting in learning and memory, healthy aging, and neurological disorders. I intend on going to graduate school and obtaining a Ph.D. in neuroscience to pursue a career as a researcher. In my free time, I enjoy creating digital art, rock climbing, and playing tabletop games with friends.


Riley Ahern (he/him)

I am originally from Santa Ana, California and study Psychology with a concentration in Addiction Counseling. I am hoping to get a PhD in Clinical Psychology and have research interests in substance use, neuroscience, anxiety, and health! Outside of research, I love to rock climb, snowboard, and mountain bike.


Marina Sazonova (she/her)

My name is Marina, I was born in Kharkiv, Ukraine, I immigrated to Los Angeles when I was 6, and found myself in Colorado in 2017. I recently graduated CSU with a Bachelor’s degree, with a concentration in cellular/molecular biology and genetics. I hope to spend my career furthering research where I can apply my passion for molecular biology and genetics to further the understanding of our world, the human experience, and the connections between physiology and psychology. As such, I have a strong interest in working with interdisciplinary and biopsychosocial studies. I am taking a couple of gap years to gain research experience, find the best graduate program for me, and to volunteer in Ukraine as much as I can. I spend my free time connecting with nature, learning new things, playing video games, and spending time with my husband and our two cats.


Devin Henry (he/him)

I am a Mind, Brain, and Behavior Psychology Major here at CSU in my first year. In the future, I look forward to achieving a PhD in the realm of Cognitive Neuroscience. As a researcher in this field, I plan to explore ways to help those with PTSD and substance use issues by learning how new neural connections are made. In my free time I find myself playing table-top games, exploring the mountains, and researching alternative medicines.


Fiona Gilfillan (she/her)

I am an undergraduate Psychology major here at CSU, following the Mind, Brain, and Behavior concentration. I plan to pursue a PhD in Cognitive Neuroscience and conduct research. I am particularly interested in psychedelic neuroscience and neurophenomenology. In the future, I hope to conduct research that leads to a better understanding of the neural correlates of consciousness through research with neuroimaging and psychedelics.

In my free time, I like to build Legos, do puzzles, binge TV, and go to drag shows!


Wes MacLean (he/him)

I am a senior Psychology major concentrating in addiction counseling. I am originally from Colorado, raised in Los Angeles, and lived in New England, D.C. and Florida before returning to Colorado in 2019. I am interested in harm reduction, reducing stigma and working with underserved populations. I plan on attending graduate school for a master’s degree in addiction counseling. In my free time, I love to be outside hiking and skiing or relaxing at home with my cats. 


Dane Roesler (he/him)

I am a 4th-year student in behavioral and cognitive neuroscience with a minor in biomedical sciences. Originally I am from Peoria, Illinois but my parents recently retired to Vail, Colorado. After undergrad, I am planning on either going to medical school or graduate school to pursue my interest in psychopharmacology to help those with mental disabilities. I am really excited to get experience in this lab to understand how drugs are manipulating how we think and feel in real-life scenarios. When I am not focusing on school, I enjoy hiking, skiing, traveling, and concerts for local bands.


Joseph Cameron (he/him)

I am a 3rd year psychology student at CSU. I was born and raised here in Fort Collins. I am interested in the study of addiction and counseling. My current interest is in methamphetamine addiction, harm reduction, and the improvement of treatments for those who have substance use disorder. I plan to attend graduate school and get a masters or Ph.D. in Clinical and Counseling Psychology. In my spare time I like to watch a good Netflix movie with my husband and our dog.


Perri Freeman-McKeon (she/her)

I’m a fourth year undergraduate studying psychology in the general concentration. I’m interested in addiction counseling, harm reduction, and understanding what influences addiction. In the future I hope to work with people struggling with substance use disorder. Outside of school I listen to as much music as possible, visit my family in Denver, and create multimedia art. 


Katelyn Weldon (she/her)

I recently graduated from Colorado State University with a Bachelor of Science in psychology. After taking some time off from school, I plan to pursue a PhD in clinical psychology. My research interests revolve around the biopsychosocial mechanisms behind comorbid substance use and eating disorders. Additionally, I am passionate about harm reduction and working to address treatment disparities within LGBTQ+ populations. In my free time, I like reading, live music, hiking, and hanging out with my dog.


Bridgette Coughlin (she/her)

My name is Bridgette, I was born and raised in Colorado. I am currently a senior at CSU, finishing my undergraduate degree in biology with a minor in biomedical sciences. Throughout my time at CSU, I have found a strong interest in neuroscience, specifically in neurobiology systems. I plan on attending graduate school to become a physician assistant. When not at school, I love to spend time with my friends playing card games, paddleboarding, climbing, and anything else in the outdoors!


Cullen Donnelly (he/him)

I am a second-year student at CSU majoring in psychology, with a clinical/counseling psychology concentration. My research interests are the effect of substance use on psychological disorders and investigating if these substances can be used to treat these disorders. I hope to attain a PhD in Clinical Psychology. My interests beyond research include tabletop gaming, hiking, and playing video games. 


Scout Watson (she/her)


Bella Packwood (she/her)


Carter Bruning (he/him)


Marco Rossi (he/him)


Lab Alumni


Mira Urushima (she/her) – 2023

Morgan Wright (she/her) – 2023

Patrick Gonzalez, B.S. (she/her) – 2021-2023

Leila Zulic, B.S. (she/her) – 2021-2023

Taylor Knox, B.S. (she/her)

Wyatt Taylor (he/him)

Hector Gutierrez, M.S. (he/him) – 2021-2022