People

Kathleen Poston, MD, MS

Dr. Kathleen Poston is the Edward F. and Irene Thiele Pimley Professor of Neurology and the Neurological Sciences and Professor, by courtesy, of Neurosurgery. Dr. Poston received her Bachelor’s of Science in Bioengineering at the University of Pennsylvania and her Master’s Degree in Biomedical Engineering at Vanderbilt University. She also obtained her medical degree from Vanderbilt University and then completed her Neurology residency training at UCSF, where she was Chief Resident. She completed a fellowship in clinical Movement Disorders under the mentorship of Dr. Stanley Fahn at Columbia University and post-doctoral training in Functional Neuroimaging with Dr. David Eidelberg at the Feinstein Institute.

When not at the lab, Dr. Poston enjoys spending time with her family and traveling. She is an avid animal lover and, if not for her husband’s voice of reason, would adopt every stray who crosses her path. She currently shares her home with two loving cats. As a former competitive swimmer and synchronized swimmer, she is also an exercise enthusiast and is currently training for a triathlon.

Marian Shahid-Besanti, MSc
Research Program Manager

Marian received her Bachelor's of Science in Neurobiology, Physiology, and Behavior from the University of California, Davis and her Master's of Science in Clinical Research Organization and Management from Drexel University. Before joining the Poston Lab, Marian worked as a Clinical Research Coordinator at UCSF in the Division of Clinical Pharmacology on various pharmacokinetic studies looking at nicotine metabolism and the effect on cognition in smokers, and the clinical pharmacology of electronic cigarettes. Marian is interested in learning more about cognitive decline and behavioral changes in individuals with Parkinson's disease. While not at work, Marian enjoys spending time with friends and family, playing volleyball and basketball, and watching her favorite Bay Area sports teams (go Warriors!).

If you are interested in participating in our research studies, please contact Marian at:

Phone: (650) 723-0060
Email: mshahid@stanford.edu

Eva Müller-Oehring, PhD
Senior Research Scientist

Dr. Eva M. Müller-Oehring is a Senior Research Scholar with a joint appointment in the Departments of Neurology and Psychiatry at Stanford University School of Medicine, and at SRI International. Dr. Müller-Oehring received her undergraduate and graduate education in Germany, where she studied Psychology at the University of Trier and obtained her Ph.D. in Neuropsychology and Cognitive Neuroscience at the School of Medicine, Otto von Guericke University Magdeburg (OVGU). She did her Clinical Psychology postgraduate studies at the Institute of Behavioral Therapy Lübben (Germany) in accordance with the German Approbation Law for Clinical Psychology, and her internship in at the Department of Psychiatry at OVGU. She completed her postdoctoral fellowship in neuroimaging, alcohol use disorder, and psychiatric diseases affecting the brain with Dr. Edith V. Sullivan at Stanford Psychiatry (USA).

Dr. Müller-Oehring's research interests aim to advance our understanding on ‘how the human brain works’ by studying the relationship between brain structure and function using multimodal imaging approaches in healthy and degraded brain systems. Her current studies focus on neurodegenerative processes, cognitive impairment, motor dysfunction, and modulators of disease severity in people aging with HIV infection, in Parkinson’s disease, and alcohol use disorder. In addition, she studies the dynamic neurodevelopmental plasticity in adolescents transitioning to adult cognitive maturity and emotional control as part of the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA). At Dr. Poston’s laboratory, Dr. Müller-Oehring is expanding her neuroimaging research to PET/MR aiming to identify biomarkers underwriting the functional status in Parkinson’s disease.

Outside of work, Dr. Müller-Oehring enjoys nature, being around horses, running, hiking, and skiing in California and the Alps, and summitting Mount Whitney with her family.

Joe Winer, PhD
Instructor

Joe Winer completed his PhD in Psychology at UC Berkeley, where he combined objective and subjective sleep assessment with PET imaging to investigate connections between sleep disruption and Alzheimer's disease in healthy aging. Since joining the Poston Lab in 2021, Joe’s research has explored how tracking sleep and other factors in everyday life can provide information about brain health and cognitive trajectories in aging and neurodegenerative diseases.

Michaela Pelta
Clinical Research Coordinator

Michaela graduated from the University of Southern California with a B.A. in Health and Human Sciences and an M.S. in Narrative Medicine. Her graduate work focused on how photography and storytelling can help convey the lived experience of invisible chronic illness. She currently works on the Blood-Based Markers Study at the Poston Lab. Prior to joining the lab, Michaela interned at the Ellison Medical Institute, a cancer research and treatment center, where she supported educational outreach initiatives aimed at making cancer research more accessible. She also worked at the USC Center for Health Equity, contributing to a longitudinal study on tobacco use among Latino communities in California.

Originally from San Francisco, Michaela grew up swimming competitively. In her free time, she enjoys long walks with her two dogs, photography, and discovering new coffee spots. She hopes to pursue a career in medicine.

Daria Shariff
Clinical Research Coordinator

Daria graduated from the University of California San Diego (UCSD) with a B.S. in Cognitive and Behavioral Neuroscience. She is interested in understanding brain function and dysfunction, such as with psychological and neurological disorders. In the Pelham Lab at UCSD, she conducted research in psychopathology with a focus on trauma and substance use. She was also involved in a study at the HIV Institute examining the effects of HIV, adversity, and cannabis use on neurocognition.

In the Poston Lab, she is excited to integrate her prior research in psychopathology with her passion for neurological disorders. She is currently working on a project that aims to understand neurocognitive changes in HIV and Parkinson's disease. She believes the profundity of studying the brain is most compelling when considering the impacts of such disorders, and she plans to pursue a career in clinical neuroscience and psychology. Apart from research, Daria enjoys reading, writing, and traveling. Her recent summer trips abroad were to Mexico, Lebanon, and Turkey.

Noah Siddiqui
Clinical Research Coordinator

Noah graduated from Colorado College with a B.A. in neuroscience. His undergraduate research focused on indirect, immune-regulated communication between the gut and the brain. While working as a research assistant at the University of Colorado, he worked to develop a behavioral model of cognitive impairment in sepsis-associated encephalopathy. Noah joined the Poston Lab excited to combine his preclinical background with his passion for clinical neuroscience and the improvement of care for patients with neurodegenerative disease. He is currently coordinating a gut-brain biomarker study in Parkinson’s disease and plans to pursue a career in clinical psychology. Noah’s time outside the lab is spent hiking, fishing, golfing and playing the guitar.

Eleanor Streit
Clinical Research Coordinator

Eleanor brings a passion for understanding the complex mechanisms underlying neurodegenerative disease to the Poston Lab. She graduated with a B.A. in Neuroscience from Columbia University in 2023, where she explored the brain-behavior relationship through research on early-life stress and reward processing at the Columbia-affiliated New York State Psychiatric Institute. Following graduation, Eleanor joined Dr. Un Jung Kang's laboratory at NYU Grossman School of Medicine, investigating the neural circuitry behind Parkinson's disease using rodent models. This experience deepened her understanding of neurodegenerative diseases and sparked a particular interest in the non-motor symptoms of Parkinson's disease.

As a new member of the Poston Lab, Eleanor is eager to contribute to advancing our understanding of these complex neurological conditions. She hopes to apply her background in translational research and foundational neuroscience to support the lab's clinical studies. Outside the lab, Eleanor enjoys knitting, gardening, and reading.

Kevin Zheng
Research Data Analyst

Kevin graduated from the University of California, Riverside with a B.S. in Biology before pursuing a Master’s in Health Data Science at the University of California, San Francisco. During his studies, Kevin conducted research under Dr. John Kornak and the UCSF Breast Imaging Research Group. His focus was on applying machine learning and statistical methodologies to interpret radiological data and related tabular information.

Kevin is currently working as a Data Analyst in the Poston Lab, where he continues to merge his interests in biology and data analysis to advance neuroscience research. Outside the lab, he spends his free time mountain biking and backpacking, embracing his love for the outdoors.

LB-SPARK/ADRC Coordinators

Veronica Ramirez
Clinical Research Manager

Veronica Ramirez is a research assistant for the Clinical Core of the Stanford ADRC. She earned her bachelor’s degree in psychology from the University of New Orleans. As an undergraduate at the University of New Orleans, she worked as a lab assistant in the department of psychology. After receiving her bachelor’s, she worked as a psychometrist and Clinical Research Coordinator at a private neuropsychology practice in New Orleans. Much of her work has involved research in behavioral neurology and forensic neuropsychology.

Larissa Gomez Castro
Clinical Research Coordinator

Before joining the ADRC and LB-SPARK at Stanford, Larissa received her B.S. in Anthropology from University of California, Davis in 2023. During her time at UC Davis, she was a part of the Pre-Med American Medical Student Association board and was also an intern at the UC Davis Comprehensive Cancer Center under Dr. Carbajal for Intestinal Metaplasia research. She also volunteered two summers in Cusco, Peru and Riobamba, Ecuador where she partnered up with local physicians and assisted medically underserved indigenous communities. Larissa also worked as a home health aide for U.S. veterans with Parkinson’s disease, Dementia, and Alzheimer’s disease. After working several years with patients with neurodegenerative diseases, she felt it was time to contribute to research to advance science and help people with neurodegenerative diseases. Larissa hopes to attend medical school and continue her passion in medicine to further help underserved communities.

Laura Mackenzie
Clinical Research Coordinator

Laura graduated from Brown University with bachelor degrees in Health and Human Biology and Latin American and Caribbean Studies. As a part of her senior thesis, she combined these interests to study the disproportionate rates of COVID-19 among Providence's Latine communities, and the role of community health organizations in addressing these disparities. After graduating, she worked for DocMatter, a start-up medical collaboration platform where she focused on neurology, dermatology, and oncology. More recently, she joined the Michael J. Fox Foundation for Parkinson's Research, where she worked with clinicians, researchers, and peers to build an online research community and to decrease barriers to data access in the neurodegenerative disease space. This year, Laura is excited to directly contribute to this research through her work with the ADRC and LB-SPARK. Outside of work, Laura enjoys all things outdoors, whether that is hiking, swimming, or lounging with a book and picnic.

T’Lesa Meadowcroft
Clinical Research Coordinator

T’Lesa Meadowcroft earned her bachelor’s degree in psychology with an emphasis in neuroscience from Westminster College in Salt Lake City, Utah. She worked as a research assistant in psychology and, after graduation in 2010, as a neuropsychometrist at the University of Utah Center for Alzheimer’s Care, Imaging and Research. In 2015, she became a Certified Specialist in Psychometry and moved to Stanford Health Care as a clinical psychometrist, before joining us at the ADRC and Pacific Udall Center.

Mackenzie “Mack” Bolen, PhD
Postdoctoral Scholar

Dr. MacKenzie “Mack” Bolen’s defining research passion is to leverage accessible and modifiable lifestyle factors to mitigate neurodegenerative risk. During her undergraduate education at Austin College in Texas, she began pursuing her interest in neurodegeneration by conducting research focused on the neuroprotective benefits of the ketogenic diet. This work evolved into an honors thesis investigating markers of inflammation in saliva from contact sport athletes and culminated in a TEDx talk on sports-related brain injuries. These experiences cemented her desire to understand the minutiae of the brain and catalyzed her decision to pursue a PhD with an emphasis in Neuroscience at the University of Florida (UF). During Mack’s training under Dr. MG. Tansey at UF, her dissertation work generated global collaborations centered on a multiomic approach that leverages machine learning to identify peripheral biomarkers and novel therapeutic targets to slow the onset or progression of Parkinson’s disease. In addition to her scholarly work, she regularly volunteered at the UF Neuromedicine Intensive Care Unit (Neuro ICU) to better understand the clinical perspective of neurodegeneration.

By blending her PhD training and experiences in the Neuro ICU, Mack hopes to actively improve the treatment of individuals living with neurodegeneration and continue to push the frontier of medicine as a postdoctoral scholar in Neurology and Neurological Sciences at Stanford. Now under the mentorship of Dr. Poston, Mack will continue to access essential training at the intersection of immunology and Parkinson’s disease, via the investigation of the gut-brain axis. As a former collegiate soccer player, Mack loves to pretend to relive her glory days during rec-league on the weekends and can also be found struggling through a Yin yoga class.

Dimuthu Hemachandra, PhD, MSc
Postdoctoral Scholar

Dr. Dimuthu Hemachandra, originally from Sri Lanka, kickstarted his academic journey with a Bachelor’s of Science in Physics from the University of Peradeniya. He later moved to Canada, where he earned an Master’s of Science in Astrophysics from the University of Western Ontario, focusing on studying the Andromeda Galaxy using infrared spectroscopy and space-based telescopes. With an aim to apply his scientific skills to improve human well-being, he transitioned from Astrophysics to Biomedical Engineering and Neuroscience. Dr. Hemachandra joined the Robarts Research Institute at the University of Western Ontario in 2018 as a Researcher where he completed his PhD at the Khan Computational Imaging Lab. Dr. Hemachandra’s research interests focus on utilizing machine learning techniques to investigate subcortical brain structures and connectivity, aiming to detect neurodegenerative diseases early on. Passionate about open and collaborative science, Dr. Hemachandra believes in the power of sharing knowledge and working together for progress. In his free time, he enjoys exploring new places, capturing moments with his camera, social dancing, and playing the guitar.

Sara Lorkiewicz, PhD
Postdoctoral Scholar

Dr. Lorkiewicz holds Bachelor of Science degrees in Molecular Biology and Psychology from Loyola University Chicago. She combined both disciplines for her master’s thesis where she studied cognitive correlates of alcohol use in people with HIV-infection at Boston University School of Medicine. She later completed her PhD in Clinical Psychology with an emphasis in Neuropsychology at Palo Alto University where she continued to explore clinical and research interests in the neurocognitive sequelae of substance use, HIV, and neurodegenerative diseases. During her clinical fellowship in Neuropsychology, she specialized in the evaluation of individuals with complex neurological and neurogenerative diseases at the Michael E. DeBakey VAMC and worked collaboratively with researchers at Baylor College of Medicine and the University of Houston to study older adults with HIV as well as cognitive fluctuations in individuals with neurodegenerative diseases.

In the Poston Lab, Dr. Lorkiewicz plans to expand her understanding of neurocognition by studying neurobiological correlates of cognitive change. She is specifically interested in identifying early neuroimaging biomarkers of movement disorders and other neurodegenerative processes that may predict disease progression, nuanced patterns of cognitive impairment, and transition to more severe forms of dementia to inform intervention strategies. Outside of the lab, Dr. Lorkiewicz enjoys traveling and outdoor activities such as running, hiking, or skiing. She can often be found playing with her dog and cat and loves spending time with friends and family.