Lab Members

Ryan Darby, MD, is a behavioral and cognitive neurologist whose work spans behavioral neurology, neuroimaging, cognitive-affective neuroscience, and bioethics. He is Chief of the Behavioral and Cognitive Neurology Division and Vice Chair of Research for the Department of Neurology at Vanderbilt University Medical Center (VUMC). He directs the Vanderbilt Center for Neurodegenerative Disease Research, the Frontotemporal Dementia (FTD) Center, and the Tennessee Memory Care Assessment Network (MCAN), a statewide effort to improve dementia assessment and care.

Dr. Darby’s research aims to understand the neurobiological mechanisms that give rise to abnormal behavior in neurodegenerative disease, using experimental decision-making tasks combined with neuroimaging. His central hypothesis is that complex behaviors arise from coordinated activity across brain networks rather than from any single region. To test it, he has used innovative neuroimaging methods, including lesion network mapping, coordinate-based network mapping, and atrophy network mapping. These methods have shown that lesions causing delusions, criminal behavior, and disordered free will perception fall within the same symptom-specific networks, and that seemingly inconsistent findings across neuroimaging studies, and heterogeneous patterns of atrophy in patients with the same symptoms, converge on shared networks. His work on antisocial behavior in FTD, including distinct rule-breaking and aggressive subtypes linked to ventromedial and orbitofrontal prefrontal atrophy, also informs the intersection of neuroscience with legal and forensic questions.

His current work translates these network concepts into mechanistic clinical trials and new symptomatic treatments across FTD, Lewy body disease, and Alzheimer disease. This includes his role as PI of a study of 5-HT2A receptor target engagement and functional neuroimaging changes in patients with Parkinson disease psychosis treated with pimavanserin, and his role as site PI in several ongoing FTD clinical trials.

Dr. James Eaton is a neurologist and an Assistant Professor of Neurology at Vanderbilt Health. Dr. Eaton’s research interests include the interplay between inflammation and the immune system with neurodegenerative disease. Dr. Eaton sees memory referral patients as part of the Division of Behavioral and Cognitive Neurology in the Department of Neurology and serves as a co-investigator with the Vanderbilt Memory and Aging Project and the Vanderbilt Alzheimer’s Disease Research Center.

Dr. Eaton completed medical school at the Zucker School of Medicine in New York. He completed his residency in neurology at Vanderbilt University Medical School followed by a neuroimmunology fellowship and a cognitive and behavioral neurology fellowship at Vanderbilt. He joined the Vanderbilt faculty in 2022.

Dr. Ciaran Considine’s research interests involve investigation of the relationships between neuropsychological functioning, sleep disorders, and autonomic functioning within neurological conditions. He is the supervising neuropsychologist for the Vanderbilt site’s ALLFTD study, lead by Dr. Darby, as well an attending neuropsychologist for the Vanderbilt Frontotemporal Dementia Clinic.

Dr. Brown is a movement disorder specialist who is licensed to practice medicine in Tennessee and Kentucky, and has been a member of the American Board of Psychiatry and Neurology since 2019. She joined Vanderbilt Health faculty in July 2019 as a postgraduate movement disorders fellowship and has stayed on as an Assistant Professor. She is the director of the Vanderbilt CurePSP Center of Care. 

Jayden joined the Department of Neurology as a postdoctoral research fellow in 2022 after completing her PhD in Speech, Language and Hearing Sciences at Boston University where she worked on better understanding the functional localization of the language network. Her current research focuses on studying social cognitive and decision-making brain-behavior relationships in neurodegenerative diseases by relating neuropsychological and psychometric measures with multimodal MR imaging methods.

Dr. Kilian Hett is a computational neuroimaging scientist and Research Assistant Professor in the Department of Neurology at Vanderbilt Health. His research interest focuses on the development of advanced magnetic resonance imaging analysis methods to investigate neurodegenerative diseases. His work integrates quantitative MRI, deep learning, and computational modeling to characterize brain structures, cerebrospinal fluid physiology, and disease-related changes in the neurofluid system.

Dr. Brito is an Instructor in Behavioral and Cognitive Neurology at Vanderbilt. Her research interests and experience have included a range of topics, including second-language acquisition, aphasia, aging and working memory, and Huntington’s disease. Clinically, she sees patients living with a variety of neurodegenerative conditions. She has a particular interest in medical education and helps run the Bedside Rounding Alliance for Internal Medicine and Neurology (BRAINs) initiative. She completed medical school at Vanderbilt University School of Medicine and neurology residency at Harvard/Mass General Brigham.

Dr Inder Raj Grewal is an Assistant Professor of Psychiatry and geriatric psychiatrist at Vanderbilt Health. She provides outpatient care to patients across the entire spectrum of geriatric psychiatric disorders and has a special interest in working with patients with neurocognitive disorders and their caregivers. She helped establish a collaborative Neurology/Neuropsychiatry clinic embedded in the Vanderbilt FTD clinic, with a focus on providing ongoing neuropsychiatric care to patients with frontotemporal dementia and Lewy Body Dementia. Dr Grewal strongly believes in optimizing collaboration and coordination of long-term multidisciplinary patient-centered care and support for families.

Dr. Michael de Riesthal is a Professor in the Department of Hearing and Speech Sciences at Vanderbilt Health, where he serves as the Director of the PhD Program and leads the Neurogenic and Communication Disorders Laboratory. His research and clinical practice focus on the assessment and treatment of motor speech, language and cognitive-communication disorders resulting from stroke, traumatic brain injuries, and progressive neurological conditions.

Dr. Gaynor is a clinical neuropsychologist and Assistant Professor of Medicine at Vanderbilt Health. She is a faculty member in the Vanderbilt Memory & Alzheimer’s Center, neuropsychology lead for the Tennessee Memory Care Assessment Network, an investigator at the Alzheimer’s Disease Sequencing Project Phenotype Harmonization Consortium coordinating center, and an investigator in the Vanderbilt Alzheimer’s Disease Research Center Clinical Core. Dr. Gaynor’s research interests include using advanced statistical and neuropsychological approaches to investigate risk and resilience in late life associated with Alzheimer’s disease and related dementias, including Limbic-predominant age-related TDP-43 encephalopathy (LATE).

Catherine Cerroni is a Clinical/Translational Research Coordinator in the Darby Lab. She earned her Bachelor of Science degree in Psychological and Brain Sciences and Bachelor of Arts degree in English Literature at The Catholic University of America. After graduation she did preclinical neuroscience research at Vanderbilt and ran oncology clinical trials in the Nashville area. Catherine currently manages a number of PSP clinical trials, including Amylyx ORION and Ferrer PROSPER. Additionally, Catherine assists with the Aviado Bio (ASPIRE) gene therapy trial for genetic carriers of Frontotemporal Dementia with GRN mutations (FTD-GRN).

Leann Seanez is a Clinical Research Coordinator in the Darby Lab. She earned her Bachelor of Science in Animal Science and a minor in Psychology from the University of California, Davis. Prior to joining, she did pre-clinical neuroscience research studying learning and memory in animal models. She then transitioned to running clinical studies looking at mood disorders in late-life adults. Leann currently manages clinical research trials and observational studies of adults with various neurodegenerative diseases.

Levi Pettit is a Clinical Research Coordinator I in the department of Neurology at Vanderbilt Health. He earned his Bachelor of Science degree in Psychology from Lipscomb University in Nashville. Levi's primary research interests involve moral and ethical considerations relating to the care and treatment of neurodegenerative populations, the correlation between traumatic brain injury and neurodegeneration, and biomarkers of neurodegeneration. Levi manages two studies that are investigating the use of pimavanserin in the treatment of FTD, Parkinson’s Disease, and Lewy body Dementia. Additionally, Levi works on the Decision-Making and Legal Problems in Dementia (MDM) study which is actively enrolling patients with a diagnosis of FTD, AD, and healthy aging adults.

Talia Kunin is a Clinical Research Coordinator I. She graduated from Vanderbilt University, where she earned a BS in Cognitive Studies, alongside minors in Data Science, Philosophy, and Business. Her previous research experiences span clinical, cognitive, and pedagogical domains. Talia coordinates the Decision-Making and Legal Problems in Dementia study (MDM) which is actively enrolling patients with a diagnosis of FTD, AD, and healthy aging adults.

Shannon provides operational and programmatic oversight for the lab’s clinical research and clinical trial activities. She works across the lab to coordinate research operations, strengthen clinical trial infrastructure, and develop processes that support the team from study start-up through ongoing trial management. Her work focuses on regulatory and quality oversight, program development, operational efficiency, and ensuring the research team has the resources and support needed to provide an exceptional experience for research participants and their families.

Scott Miller is a Data Analyst in the Darby Lab within the Department of Neurology at Vanderbilt Health. He earned his Bachelors of Science degree in Biomedical Engineering with a minor in Neuroscience from Purdue University Indianapolis in May 2023, and his Master of Science degree in Biomedical Engineering at the University of Michigan in December 2024. He is currently involved in multiple projects that revolve around the centralization of datasets maintained by individual research groups within the Behavioral and Cognitive Neuroscience Division to improve internal visibility and data sharing for novel research initiatives. These projects intend to culminate into a harmonization of patient data throughout the entire division to enable interdisciplinary research opportunities. Additional projects include the use of atrophy network mapping to investigate brain-behavior relationships in patients with neurodegenerative diseases.

Jeanette Saffir is an associate in pediatrics at Vanderbilt Health. She currently provides genetic counseling for patients in the Frontotemporal Dementia Clinic in the Department of Neurology at Vanderbilt Health. In addition, she sees patients in pediatric genetics, general genetics, Vascular Anomalies Clinic, and Spasticity Clinic.

She received her BS in cellular and molecular biology and her BA in psychology from California State University, Northridge and her Masters degree in Genetic Counseling from University of Utah in Salt Lake City. Prior to working at Vanderbilt, she worked as a prenatal genetic counselor in Las Vegas, NV. She joined the Vanderbilt faculty in 2021.

Behnaz Akbarian is a biomedical engineer and research fellow whose work focuses on using neuroimaging to understand brain function and neurological disease. Born in Tehran, Iran, she earned her Master of Science degree from Iran University of Science and Technology and her PhD in Biomedical Engineering from Vanderbilt University, where she conducted her doctoral research in the Darby Lab under the mentorship of Dr. Ryan Darby.

Her research interests include biomedical signal and image processing, functional MRI, electrophysiology, pattern recognition, brain stimulation, and computational neuroscience. Her current research integrates structural and functional neuroimaging with behavioral assessments to investigate frontotemporal dementia, with the goal of identifying biomarkers for early detection and disease progression and understanding the neural mechanisms underlying behavioral symptoms.

For more information about her research and publications, visit her Google Scholar profile.

Kedar Madi joined the Darby lab as a postdoctoral research fellow in October 2025. He received his Bachelor of Science in Bioengineering from the University of Pittsburgh in 2018 with a minor in Neuroscience before attending the Wake Forest School of Medicine, where he earned his Master of Science (2021) and PhD (2025) in biomedical engineering. Kedar’s research work focuses on neuroimaging pipeline development and morphometry (shape analysis) of brain structures, particularly the hippocampus, in the context of neurodegenerative disease. His current projects include the study of brain regions functionally connected to sites of neural atrophy and tau deposition in Huntington’s Disease and Alzheimer’s Disease, respectively. Additional projects and research interests include machine learning classification and shape analysis of brain regions in frontotemporal dementia.

Ms. Shibata is a PhD candidate in Hearing and Speech Sciences at Vanderbilt University whose work focuses on communication and motor changes in frontotemporal degeneration (FTD) and primary progressive aphasia/apraxia of speech (PPA/PPAOS). Her dissertation investigates laryngeal motor dysfunction as a potential early marker of broader motor involvement in FTD-spectrum disorders, integrating auditory-perceptual voice assessment, acoustic analysis, and neurologic measures of motor dysfunction. Her broader research includes perceptual analysis of connected speech in aphasia, progressive motor speech disorders, psychometrics, and cross-linguistic assessment. A central focus of Ms. Shibata's broader work is developing clinically informed support and education for people living with PPA/PPAOS and their families, drawing on years of clinical experience to translate research into practical tools and resources that are meaningful in everyday life. She is an NIH T32 trainee and works across the Darby Lab, Neurogenic Communication Disorders Lab, and Language Neuroscience Lab at Vanderbilt University.

Degree Summary: Major in Psychology

Interests in research: I’m interested in how psychological and neurological illness contribute to interactions with the criminal justice system.

Hobbies: drumming, working out, and traveling!