Our Team
The people behind the work
A collaborative group spanning clinical science, behavioral genetics, and public policy — from faculty and staff to graduate students and undergraduate research assistants.
Principal Investigator
Jonathan D. Schaefer, Ph.D., L.P.
Principal Investigator
Dr. Schaefer is an Assistant Professor of Psychology at Vanderbilt University and a licensed clinical psychologist. He joined Vanderbilt in 2023, where he directs the Schaefer Lab and the Vanderbilt University Twin Research Center (VUTRC) and teaches Abnormal Psychology and Psychiatric Epidemiology.
His research examines how environmental exposures — socioeconomic disadvantage, environmental toxicants, victimization, substance use — affect mental health. Using twin and longitudinal designs, his work tests whether these associations reflect causal processes or statistical confounding, and seeks to identify the modifiable mechanisms behind causal effects, generating actionable insights for interventionists, policymakers, and consumers.
A second line of work aims to destigmatize mental health problems and broaden the uptake of evidence-based treatments. His research and popular-science writing shows that when people are followed long enough and assessed frequently, almost everyone will meet criteria for at least one psychiatric disorder at some point in their lives.
Before Vanderbilt, Dr. Schaefer earned his B.A. at Swarthmore College and his Ph.D. in Clinical Psychology at Duke University, then completed postdoctoral training at the University of Minnesota supported by a K01 Career Development Award from NIDA. He was named an APS Rising Star in 2025.
He is particularly excited to work with trainees interested in (1) the environmental determinants of mental health, (2) behavioral genetics, and (3) using AI and mobile-phone technology to improve the measurement of both mental health and people’s social and physical environments.
Staff
Haley Komorowski
Lab Manager
Haley graduated Summa Cum Laude from the Honors Program at Auburn University in May 2022 with a Bachelor of Science in Rehabilitation and Disability Studies. She gathered research experience working on clinical trials involving study treatment for various types of dementia and neurodegenerative diseases. Haley is currently pursuing a Master of Neuroscience degree with the University of Florida. She has experience working with and recruiting vulnerable populations for research studies, neuropsychological assessments, and coordinating IRB proposals. As the Lab Manager, Haley oversees Research Assistant training and recruitment for studies, manages IRB applications and REDCap data, and more.
Matías Martinez
Postdoctoral Researcher
Matías is a postdoctoral researcher interested in how social environments and school policy impact youth’s mental health, behavior, and human capital accumulation. He holds a B.S. in Economics and a Master’s in Public Policy from Universidad de Chile, and a M.A. and Ph.D. in Human Development and Social Policy from Northwestern University. His research takes an interdisciplinary approach, drawing theoretical frameworks from different disciplines in the biopsychosocial and social sciences. He follows a quantitative approach employing causal inference and longitudinal methods typically used in policy evaluations and developmental psychology. Outside of the Lab, Matias enjoys watching the Packers and la U. de Chile, hiking, climbing, and playing tennis, volleyball, and fútbol-soccer.
Graduate Students
Ankita Mohan
Graduate Student
Ankita is a graduate student in the Vanderbilt University Clinical Science Doctoral Program and a UCEDD trainee at the Vanderbilt Kennedy Center. She joined the Schaefer Lab in 2024, where she investigates how social and environmental factors shape neurodevelopment and mental health outcomes. Her work aims to bridge research, policy, and practice. She holds a B.A. in Public Policy from William & Mary and an MHS in Social Factors of Health from the Johns Hopkins School of Public Health. In her free time, Ankita enjoys exploring the Nashville food scene, hiking with her dog, reading, and watching football (Go Birds)!
Ali Sloan
Graduate Student
Ali is a doctoral student in the Clinical Science program. After graduating from Duke University with a B.S. in Neuroscience in 2020, she joined Teach for America and served as a high school special education teacher while pursuing her M.Ed. in Curriculum and Teaching from Boston University. She then worked as a research assistant in the Early Psychosis Program at Vanderbilt University Medical Center for two years before starting her Ph.D. at Vanderbilt. Ali is interested in researching the mechanisms linking different dimensions of childhood adversity to symptoms of psychopathology. Outside of the lab, Ali enjoys drinking coffee, watching football, and hanging out with her friends and pup (fittingly named Duke)!
Kaiya Brand
Graduate Student
Kaiya is a second-year graduate student in the Vanderbilt Clinical Science Doctoral Program. She earned a B.S. in Psychology from College of Charleston, where she volunteered in many college-based and medical labs. After graduating, she worked for two years as a Program Coordinator in The Prisciandaro Lab at the Medical University of South Carolina. In this lab, she explored relationships between substance use disorders and bipolar disorder using fMRI approaches. Kaiya joined the Schaefer lab in April of 2025. She studies the effects of socioeconomic status on substance use disorders and other co-occurring psychiatric disorders. Outside of the lab, Kaiya loves surfing, skating, yoga, reading, and anything outdoors!
Undergraduate Research Assistants
The lab is powered by a large team of Vanderbilt undergraduates.
Sam Brabeck
Sophomore in Medicine, Health & Society and Cognitive Studies; interested in social determinants and maternal mental-health access.
Tristan Bron
Senior Psychology major; exploring socioeconomic status and alcohol use.
Mazli Mehr
Junior in Psychology and Medicine, Health & Society; works on participant recruitment.
Robert Fisher
Junior triple-majoring in Psychology, Law/History/Society, and German; honors thesis on substance use as a causal risk factor for incarceration.
Chloe Kim
Junior Psychology major (Spanish, Data Science minors); studies environmental effects on health behaviors.
Aidan Nazareth
Freshman in Psychology and Culture, Advocacy & Leadership; studying socioeconomic status and alcohol use.
Ruhi Patel
Junior in Psychology and Gender & Sexuality Studies; honors thesis on SES and antisocial personality disorder.
Noah Hall
Sophomore Psychology major; interested in socioeconomic status and psychopathology.
Maggie Ragland
Sophomore in Neuroscience and Psychology; studies SES and alcohol use; planning medical school.
Emily Fitzgerald
Junior in Psychology and Medicine, Health & Society; interested in longitudinal twin studies of substance use and mood.
Cristian Umana Hernandez
Junior in Psychology and Medicine, Health & Society; researching SES and psychopathology; aiming for a neuropsychology Ph.D.
Alex Wilf
Junior in Psychology and Climate Studies; explores substance use, mental health, and environment.
Yiwen Xing
Junior Psychology major (Communication Studies minor); examines substance use and psychosocial stress.
Alumni
Where some of our former members are now.
Eunice Ahn
Vanderbilt University
Now: Master’s student in Professional Counseling at the University of Pennsylvania
William Carter
Vanderbilt University
Now: Fellow at Project Horseshoe Farm, a community-health non-profit in rural Alabama
Jazz Divinity
Psychology (minor in Business), Vanderbilt University
Joseph Lanigan
Vanderbilt University · 2024
Lilian Li
Psychology and Medicine, Health & Society (minors in Biological Science and Child Psychology & Mental Health), Vanderbilt University
Charlotte Wulf
Psychology and Medicine, Health & Society, Vanderbilt University · 2024
Nandi Zhang
Vanderbilt University
Now: Research assistant in the Jiang Lab for Social and Affective Neuroscience at the University of Iowa
Weichen Sun
M.Ed., Quantitative Methods, Vanderbilt University · 2026