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War Related Illness and Injury Study Center

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Our staff consists of physicians, nurse practitioners, physician assistants, psychologists, research scientists, epidemiologists, complementary and alternative medicine practitioners, and environmental health scientists who have many years of experience seeing veterans with post-deployment health concerns. Below is a description of the clinical and research backgrounds of our current DC WRIISC staff members:


Matthew J. Reinhard, PsyD
  • Position: WRIISC Director

Dr. Reinhard is the Director of DC WRIISC. He has been with the WRIISC at the Washington DC VA Medical Center since 2008 as a clinical neuropsychologist and has seen many Veterans with a variety of post-deployment health concerns. He obtained his BA from Long Island University, his MA and PsyD from Pepperdine University (APA), and interned at the Kaiser Permanente Los Angeles Medical Center (APA). He completed a two-year post-doctoral fellowship in neuropsychology at the University of California-Los Angeles (UCLA), Semel Institute for Neuroscience and Human Behavior. Dr. Reinhard has also worked as a clinical psychologist in the PTSD treatment program at the Washington DC VAMC. He has unique expertise in the area of military, occupational, and environmental exposures and neuropsychological assessment and recently published neuropsychology research in the areas of toxin exposures and military cohorts. His current research area of interests are brain behavior relationships in PTSD, Gulf War Illness, and CIM. He holds an academic appointment at the Associate Professor rank from Georgetown University Medical School Department of Psychiatry.

Contact Dr. Reinhard at 202-745-8249.

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  • Position: Medical Director and Deputy Director

Dr. John Barrett joined the War Related Illness and Injury Study Center in November 2019 after retiring from the Army with over 30 years of service at the rank of colonel. He most recently served at the Uniformed Services University of the Health Sciences (USUHS) where he was the Army Senior Service Leader and the Deputy Director of the Division of Epidemiology and Biostatistics. Dr. Barrett began his military service after high school, enlisting as an Army medic. He then attended the University of California, Davis, while serving as a National Guard flight medic, and commissioning as a Second Lieutenant through Army ROTC. He received his medical degree from USUHS and later attended the University of Washington, receiving Master of Public Health and Master of Science degrees. As an Army Medical Corps officer, Dr. Barrett has served in several leadership, operational, teaching, clinical, and deployed positions in the U.S. and abroad. He is a Fellow of the American Academy of Family Physicians, the American College of Preventive Medicine and the American College of Occupational and Environmental Medicine. His academic interests include military occupational and environmental exposures, population health, clinical health services, lifestyle medicine and brain health, and leadership in healthcare. Dr. Barrett’s awards include the Defense Superior Service Medal, the Army Surgeon General “A” Designation, the Order of Military Medical Merit, and he was recognized as a Distinguished Member of the Regiment, Army Medical Department.

Contact Dr. Barrett at 202-745-8249.

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Nate Allen, BS
  • Position: Grant Manager

Mr. Allen, BS, is a Research Grant Manager at DC WRIISC and graduate of Trinity College, CT. He is currently a research coordinator and primary investigator for WRIISC studies including inhibitory reflex control via eye movements, integrative and alternative medicine for Gulf War Veterans, and the intersection of health and mobile technologies. He hopes WRIISC’s interdisciplinary work with multi-symptom illnesses, TBI, and PTSD will contribute to positive health outcomes for future Veterans.

Contact Mr. Allen at 202-745-8000, ext. 55474.

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Charity B. Breneman, PhD, MSPH
  • Position: Senior Exercise Physiologist

Dr. Breneman is an Exercise Physiologist with the DC WRIISC. She graduated from Brigham Young University with a BS and MS in Exercise Science. She went on to earn a PhD in Exercise Science with an emphasis in health aspects of physical activity and a MSPH in Epidemiology from the University of South Carolina (USC). Dr. Breneman also completed a postdoctoral fellowship in health services research at the Rural and Minority Health Research Center at USC. Her current area of research includes examining the bidirectional relationship between exercise and sleep, the acute and chronic effects of exercise on post-deployment health, and the individualization of exercise training prescriptions.

Contact Dr. Breneman at 202-745-8249.

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Ryan C. Brewster, PhD
  • Position: Clinical Neuropsychologist

Dr. Brewster is a Clinical Neuropsychologist and Neuropsychology Fellowship Director at the WRIISC-DC.  He obtained an undergraduate degree from the University of Miami and a PhD in Clinical Psychology through the joint Clinical Psychology and Neuropsychology and Cognitive Neuroscience programs at Georgia State University. Dr. Brewster then completed a clinical internship in Adult Neuropsychology at the University of California-Los Angeles (UCLA) Semel Institute for Neuroscience and Human Behavior and a two-year post-doctoral fellowship in Clinical Neuropsychology specializing in Traumatic Brain Injury/Rehabilitation at the West Los Angeles VAMC.  His clinical responsibilities include conducting neuropsychological assessments of Veterans with a wide range of complex neurocognitive and emotional concerns.  His current research interests are in the combined application of neuroimaging and neuropsychological assessment to better understand TBI and epilepsy, cognitive rehabilitation following TBI, and disentangling overlapping cognitive and emotional symptoms common in mTBI and PTSD.

Contact Dr. Brewster at 202-745-8000, ext. 56800.

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Thomas Chacko, PhD
  • Position: Information Research Scientist

Dr. Chacko is a research scientist with the WRIISC DC’s Complex Exposure Threats Center (CETC). He completed his doctoral training in counseling psychology and his post-doctoral training included data science approaches (Rochester Regional Hospital, Rochester, NY) and clinical neuropsychology (Neuropsychology and Concussion Management Associates, Rockport, ME). Dr. Chacko completed two independent research studies on Vietnam Veterans focusing on PTSD, TBI, sleep disorders, posttraumatic growth, and resilience. During his doctoral training, he worked with the Community Living Center and Posttraumatic Stress Disorder (PTSD) Program at VA Western New York Healthcare System, Batavia, NY. His psychology PhD dissertation examined the co-occurrence of PTSD, sleep disorders, eating disorders and obesity among Vietnam Veterans with a latent variable approach. Previously he completed a Masters in Psychology and a PhD in Social Work. His Social Work PhD dissertation research focused on post-trauma adaptations and resilience among Vietnam combat Veterans. His current research interests include complex military exposures and their impact on various health outcomes including TBI and PTSD, from a neuropsychological perspective and data science approach.

Contact Dr. Chacko at 202-745-8249.

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Jeremy Chester, BS
  • Position: Data Manager

Mr. Chester, BS, is a Data Manager at DC WRIISC. He has a BS in Biochemistry from Binghamton University. He has worked for the Department of Veterans Affairs since 2016, and he previously served in the United States Marine Corps Reserves for six years, including a one-year active duty deployment in support of Operation Iraqi Freedom. He has conducted research on a variety of topics, including the genetic basis of thyrotoxicosis, the media’s portrayal of Chronic Multi-Symptom Illness, treatments for Gulf War Illness, and the history of translational research in Gulf War Illness. He has published research on thyroid hormone receptor disease. He is currently involved in several research studies with the WRIISC, including treatments for Insomnia in Gulf War Veterans, identifying biomarkers, the course of illness, and targeted treatment approaches for Gulf War Illness, and clinical outcomes of Mefloquine use. He is involved in clinical operations at the WRIISC, including database queries and management and a value stream analysis of clinical operations. He also is involved in WRIISC educational operations, including development of an educational module on depleted uranium exposure and a remote health coaching project.

Contact Mr. Chester at 202-286-9004.

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Timothy Chun, BS
  • Position: Health Science Specialist

Mr. Chun, BS is a research assistant at the DC WRIISC. He received his bachelor’s degree in Community Health at the University of Maryland, College Park. He has a background in electroencephalogram (EEG) research and will continue this research at WRIISC. Mr. Chun looks forward to expanding his experience in research and to assist the WRIISC team to achieve their goals.

Contact Mr. Chun at 202-745-8000, ext. 55818.

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Ashley Chung, MPH
  • Position: Communications Specialist

Ms. Chung is a Communications Specialist with the DC War Related Illness and Injury Study Center (WRIISC) Complex Emerging Threats Center (CETC). Originally a Maryland/DC native, Ms. Chung is a graduate of University of Maryland, College Park where she obtained a Bachelor of Science in Neurobiology and Physiology. She began her career at the Center for Biologics Evaluation and Research at the Food and Drug Administration researching ways to improve Anthrax vaccine stability. In 2015, she moved to Pittsburgh, PA to pursue a Master of Public Health (MPH). Her research focused on Infectious Disease Management, Intervention and Community Practice, specifically with HIV/AIDS and LGBTQIA Health. Upon graduation, she worked in various capacities combining her passions for community outreach, disease prevention, and population health. She served as a Program Officer for Federal Ryan White Act funds for the 9-county southwestern PA region and statewide Minority AIDS Initiative, managed AIDS Free Pittsburgh, a local public health initiative aimed at reducing HIV and AIDS incidence within Allegheny County, PA, and worked in Infection Prevention and Control at the Center for Quality for the UPMC Health System, operationalizing COVID-19 guidance for staff and patients, implementing processes for Mpox vaccination, and more. Ms. Chung is excited to learn more about Veteran health care and be a part of improving health outcomes for this population.

Contact Ms. Chung at 202-330-6003.

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Michelle E. Costanzo, PhD
  • Position: WRIISC DC Research Director

Dr. Costanzo is the Research Director at the DC WRIISC and has a faculty position as a Research Assistant Professor of Medicine at the Uniformed Services University of the Health Sciences (USUHS). She has over 15 years of human subjects research experience with 8 years experience specifically focused in a military research environment (Department of Defense and Veterans Affairs). She has a strong publication history related to post-deployment health topics and expert populations such as elite athletes and physicians, including the 2017 Military Medicine Article of the Year for her work as lead author of the article "Psychophysiological Investigation of Combat Veterans with Subthreshold Post-traumatic Stress Disorder Symptoms."  Specifically, her military-relevant research has utilized psychophysiology and neuroimaging to examine post-traumatic stress disorder and mild traumatic brain injury during fear conditioning, combat-related virtual reality, affective stroop, and telemedicine to reveal insight into the etiology of persistent symptoms associated with deployment. Her recent interest has focused on behavioral interventions aimed at augmenting cognitive control and executive functioning based on neuroscientific understanding of stress, brain structural and functional plasticity that could help Veterans achieve the self-regulation competence to enable them to master patient-driven healthcare. She holds a BS in Neurobiology, Physiology, and Behavior from the University of California, Davis and a PhD in Neuroscience and Cognitive Science from the University of Maryland, College Park (UMD). She was trained in the acquisition and analysis of electroencephalography (EEG) at the UMD as well as in functional Magnetic Research Imaging at the National Institutes of Health (NIH) and the Georgetown University Medical Center. In addition to her scientific training, she has over a decade of experience with research administration and program management, ranging from her work at the National Science Foundation and the White House Office of Science and Technology Policy to her responsibilities as a study manager for NIH, USUHS, Walter Reed National Military Medical Center and WRIISC clinical studies. This has afforded her considerable experience with Federal government program management, budgeting, regulatory compliance and science policy. In addition, she has served as a reviewer for peer-reviewed journals, IRB scientific review and successfully acquired grant funding during her appointment at the VA.  Dr. Costanzo is leading the research team in developing the next generation of rehabilitation, treatment and diagnosis for Veterans through leveraging both clinical and research resources that the VA currently offers and through partnership with other institutions.

Contact Dr. Costanzo at 202-745-8000, ext. 56973.

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Lucas E. Crock, MA
  • Position: Health Science Specialist

Mr. Crock is a Health Science Specialist with the DC WRIISC. He has a BS in Psychology from King’s College, Wilkes-Barre, PA, and a MA in Psychological Science from the Catholic University of America in Washington, DC. His background includes conducting research on a variety of topics such as group therapy treatments, moderators for intervention efficacy, and treatments for Gulf War Illness. He is currently involved in multiple studies with the WRIISC examining the efficacy of alternative treatments for Gulf War Illness, telehealth interventions, and treatments for Insomnia in Veterans.

Contact Mr. Crock at 202-745-8000, ext. 57553.

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Stephen Fischer, MD, MPH, FACPM, FACOEM
  • Position: Associate Director for Clinical Operations

Dr. Stephen Fischer joined the War Related Injury & Illness Study Center in 2023 after a 20 year career with the Department of Navy and Marine Corps, and 3 years at Smithsonian Institution during the COVID-19 pandemic. Dr Fischer earned a Navy scholarship and received his Medical Degree from New York University in 1999. He completed his medical internship in New Orleans, and then he served forward-deployed naval forces in the Western Pacific aboard Naval Hospital Yokosuka, Japan, and at sea with Destroyer Squadron Fifteen, from 2000 to 2004. Dr Fischer subsequently trained as an Undersea (Diving) Medical Officer and returned to forward-deployed naval forces aboard Explosives Ordnance Disposal Mobile Unit 5 in Guam, US Marianas Islands, 2005 to 2007. Dr Fischer underwent training as a Naval Flight Surgeon from 2007 to 2008 in Pensacola, Florida, and he was certified as a FAA Aeromedical Examiner. He then served with the Naval Academy’s Brigade Medical Unit while he attended Johns Hopkins and earned his MPH. After, he served with First Marine Expeditionary Force, Camp Pendleton, 2010 to 2013, and deployed to Afghanistan with the Marines. From 2014 to 2020, he served with Naval Medical Research & Development Enterprise and Walter Reed National Military Medical Center, with additional duties as Public Health Emergency Officer. Dr Fischer is board-certified, Fellow of the American College of Occupational & Environmental Medicine, Fellow of the American College of Preventive Medicine, Associate Fellow of the Aerospace Medical Association, and life member of American Society of Tropical Medicine & Hygiene.

Contact Dr. Fischer at 202-745-8249.

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Robert Forsten, DO, MS
  • Position: Senior Clinician and Psychiatry Consultant

Dr. Robert Forsten was commissioned through the Army’s Reserve Officer Training Corp (ROTC) in 1990 and attended medical school on a Health Profession Scholarship graduating in 1994 from the University of New England College of Osteopathic Medicine. Following graduation, he entered U.S. Army Active duty and completed residency and fellowship training in Psychiatry at Tripler Army Medical Center. Dr. Forsten’s notable assignments include 1st Cavalry Division Psychiatrist; Chief of Behavioral Health, 21st Combat Support Hospital (CSH), Operation Iraqi Freedom, 2003-2004, Balad, Iraq; Medical Director (Intensive Outpatient Program) and Site Director, Walter Reed Army Medical Center Residency Program, 2004-2007; US Army Special Operations Command Psychiatrist, 2007-2012 with deployment to Afghanistan in 2009 with 7th Special Forces Group. Dr. Forsten commanded the 121st CSH in Korea and the 62nd Medical Brigade at Joint Base Lewis-McChord (JBLM) and deployed as Task Force-Medical Commander to Puerto Rico and the Virgin Islands in response to Hurricane Maria from Oct-Dec 2017. He also served as Command Surgeon with US Army Pacific, Fort Shafter, Hawaii, and First Corps, JBLM. As a Soldier, Dr. Forsten completed Airborne and Air Assault schools, the Expert Field Medical Badge, Survival, Evasion, Resistance and Escape (SERE-C), the U.S. Army Flight Surgeon course, and the Deep Sea Diving Medical Officer course. He is a graduate of the U.S. Army War College with a Master of Strategic Studies. Dr. Forsten’s recognition for service include the Legion of Merit (4 awards), Combat Action Badge, the Army Surgeon General “A” Designation, the Order of Military Medical Merit, Distinguished Member of the U.S. Army Medical Department Regiment, and is a diplomate of the American Board of Psychiatry and Neurology. He retired from active duty in September 2020 at the rank of COL and started working for the VA in October 2020. He transferred to the DC WRIISC in November 2022.

Contact Dr. Forsten at 202-745-8249.

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Arghavan Hamedi, MA
  • Position: Health Science Specialist

Ms. Hamedi, MA, is a Health Science Specialist at the D.C. WRIISC. She has a B.A. in Psychology from Virginia Commonwealth University and an M.A. in Psychological Science from the Catholic University of America. Her research background in cognitive psychology includes examining a variety of topics such as emotion regulation, rumination, and brief mindfulness-based interventions. She was also an advanced cognitive brain trainer and eye-tracking coder. Her clinical research background involves military suicide prevention with active duty service members and investigating the role of attentional biases on suicide ideation. Ms. Hamedi is excited to work with the WRIISC team to help them meet their research goals and provide excellent patient care.

Contact Ms. Hamedi at 202-745-8000, ext. 56824.

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Walt Jachimowicz, MSN, NBC-HWC
  • Position: WRIISC Health Wellness Coach

Mr. Jachimowicz is a Health Wellness Coach and a registered nurse who serves as a Health Coach for the DC WRIISC. He obtained his BSN from Madonna University and his MSN from the University of Detroit Mercy. He is a Board-Certified Health Coach through the National Board of Health and Wellness (NBC-HWC). He recently retired from the Department of Veterans Affairs Healthcare System after 25 years of service. He served in the United States Marine Corps as an active-duty reserve officer. Mr. Jachimowicz works with Veterans who have been diagnosed with Chronic Multi-symptom Illness (CMI), Gulf War Illness (GWI), Traumatic Brain Injury (TBI), and Post Traumatic Stress Disorder (PTSD) to obtain optimal health outcomes by making sustainable lifestyle changes and completing medical and lifestyle clinical recommendations. He works with Veterans to help them achieve their personal health and wellness goals and develop strategies to meet these goals which may include reducing stress, improving sleep, lowering risk of chronic illness, and/or losing weight.

Contact Mr. Jachimowicz at 202-745-8249.

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Owen Killy, BS
  • Position: Research Assistant

Owen Killy is a research assistant for WRIISC DC’s Complex Exposure Threats Center (CETC). He received his undergraduate bachelor’s degree in psychology from Hobart College where he focused on developmental and sleep psychology, along with statistical analysis. Mr. Killy is interested in Veteran military exposures and how these exposures impact health outcomes. At CETC, Mr. Killy will be working on data analyses for Veteran exposure assessments.

Contact Mr. Killy at 202-745-8249.

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Calvin Lu, MA, PhD
  • Position: Advanced Postdoctoral Research Fellow

Dr. Lu is a Cognitive-Motor neuroscientist with the DC WRIISC. He got his MA and PhD from the University of Maryland, College Park in the department of Kinesiology. His dissertation focused on the impact of autonomic regulations on enhancing precision cognitive-motor performance when performing under pressure. Dr. Lu aims to expand on his previous knowledge of human performance and the multi-systems approach to health in order to better diagnose and address possible interventions designed to remedy inefficiencies of underlying health conditions.

Contact Dr. Lu at 202-745-8249.

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Rebecca McCullers, MA, RN, RYT, HWC
  • Position: Health Coach

Ms. McCullers is a Registered Nurse, Registered Yoga Instructor, and Certified Health and Wellness Coach who supports the DC-WRIISC through health and wellness coaching. She served in the United States Air Force for 23 years as an officer, leader, nurse, and Inspector General. She earned her BSN from the University of North Carolina at Charlotte, a MA in International Relations from Webster University, and a Certification in Health and Wellness Coaching from Georgetown University. Ms. McCullers has worked in many diverse clinical and operational settings in the military health care system. She is passionate about health promotion and wellness and how these practices can help Veterans with chronic multi-symptom illnesses. Ms. McCullers believes in the transformative power of taking charge of your health, and engaging in holistic and integrative health practices to optimize overall well-being.

Contact Ms. McCullers at 202-550-4248.

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Diana Ngo, MPH, RN
  • Position: Health Science Specialist

Ms. Ngo is a Health Science Specialist at DC WRIISC. She began her public health career in cancer control with a focus on ethnic health disparities. At the American Cancer Society and as a research assistant at Stanford University, she supported and spearheaded novel youth-led initiatives to create awareness of cancer disparities through community-level interventions ranging from grassroots outreach to celebrity partnerships. At the University of California San Francisco (UCSF), she participated in the Asian American Network for Cancer Awareness, Research, and Training program and produced a televised bilingual public service announcement for the UCSF Vietnamese Community Health Promotion Project, a community-academic research center. Ms. Ngo was then part of the team to stand up NextFlex, establishing the marketing arm of the Manufacturing USA institute jointly managed by the Air Force Research Laboratory and the Army Research Laboratory. Through this experience, she gained a deeper appreciation of warfighters' burdens and is humbled to serve their needs by joining WRIISC as a health science specialist for Project IN-DEPTH, a study on Gulf War Illness. Ms. Ngo obtained an AS in Nursing at Bristol Community College, a BS in Health Science Education at University of Florida, and an MPH at San José State University.

Contact Ms. Ngo at 202-745-8249.

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Jose Ortiz, MD, MPH, FACOEM
  • Position: Associate Director of Complex Exposure Threats Center (CETC), Senior OEM Consultant

Dr. Jose (Joe) Ortiz joined the War Related Illness and Injury Study Center in August 2023 after retiring as an Army Colonel with over 30 years of service. He most recently served at the Walter Reed National Military Medical Center (WRNMMC) as the Chief of the Occupational and Environmental Medicine (OEM) Service, and he has been an Assistant Professor at the Uniformed Services University of the Health Sciences (USUHS) since 2019. Dr. Ortiz began his military career through Army ROTC at Duke University, where he graduated as a Distinguished Military Graduate with a degree in Psychology/Philosophy. He received his medical degree from USUHS, where he also received his Master of Public Health degree during his Residency in OEM. As an Army Medical Corps officer, Dr. Ortiz has served in several leadership, clinical, deployed, and teaching positions in the U.S. and abroad, including deployments to Kosovo and Afghanistan, serving at the Command Surgeon for the Joint Munitions Command/Army Field Support Command, serving at the Army Surgeon General’s Consultant for Occupational Health and Environmental Medicine, and serving as the Associate Program Director for the OEM Residency at USUHS. He is a Fellow of the American College of Occupational and Environmental Medicine and is currently the President of the Metro Washington (D.C.) College of OEM. His academic interests include military occupational and environmental exposures, population health, Airborne Hazards and Open Burn Pit Registry data analysis, and heat injury prevention. Dr. Ortiz’s awards include the Legion of Merit, Bronze Star, Defense Meritorious Service Medal, and the Army Staff Identification Badge, and he has also completed Airborne and Flight Surgeon schools.

Contact Dr. Ortiz at 202-745-8000, ext. 57640.

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Jeffrey M. Page
  • Position: Research Information Scientist

Mr. Page is a Research Information Scientist at the Complex Exposure Threats Center (CETC). With a transdisciplinary background in Biochemistry, Computer science, and Computational Biology, Mr. Page brings years of interdisciplinary research experience, focusing on analyzing complex datasets, predictive modeling, and numerical optimization. He has a proven track record of collaborating across disciplines to investigate regulatory imbalances in neuro-immune and neurotransmission systems, aiming to understand and address complex disorders such as Gulf War Illness and PTSD. He holds an MSc in Bioinformatics from Rochester Institute of Technology and a BS in Biochemistry from Ithaca College.

Contact Mr. Page at 202-745-8249.

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Gabriel Pena, PhD
  • Position: Advanced Health Fellow

Dr. Pena is an Advanced Health Fellow with the Complex Exposures Threats Center (CETC) at the WRIISC-DC. He is an exercise physiologist and neuroscientist by training and his work has centered around brain-peripheral body system crosstalk in biological aging and age-related pathologies. He received his BS and MS in Exercise Science and Health Promotion (exercise physiology concentration) from Florida Atlantic University, and his Ph.D. in Kinesiology (cognitive motor neuroscience concentration) from the University of Maryland – College Park. His dissertation work focused on addressing brain glucose transport and oxidation in response to common mechanisms of altered blood flow in cardiovascular disease. Dr. Pena aims to build on his experience and contribute to the research objectives of CETC by studying the immune, metabolic, cardiovascular, and neurophysiological/neurocognitive consequences of military environmental exposures and whether they relate to each other from an integrative point of view.

Contact Dr. Pena at 202-745-8249.

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Kamila Pollin, PhD
  • Position: Health Science Specialist

Dr. Kamila Pollin is an Health Science Specialist with the DC WRIISC. She completed her undergraduate degree at Rutgers University and her PhD in Applied Physiology from the University of Delaware. Her dissertation examined the impact of dietary sodium on cerebral blood flow regulation in healthy, young adults. She joined the DC WRIISC team as an Advanced Postdoctoral Research Fellow and then transitioned into the Health Science Specialist role. She supports various research projects aiming to assist with post-deployment health concerns in Veterans. She is currently involved with Project IN-DEPTH, assisting with exposure analysis and communications with the National Institutes of Health. Her general research interests include understanding the impact of nutrition and exercise on health outcomes.

Contact Dr. Pollin at 202-215-4183.

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Michelle Kennedy Prisco, MSN, ANP-C
  • Position: Environmental Exposure Specialist

Ms. Prisco is a former Army Nurse Corps officer who is a deployment health clinician, educator, and researcher for the VA’s national post-deployment health center titled the War Related Illness and Injury Study Center (WRIISC).  She has worked at the Department of Veterans Affairs for over 25 years and advises on VA national working groups on post-deployment health matters.  Ms. Prisco develops and presents national VA wide webinars and training programs aimed at improving post-deployment health awareness in VA providers.  She conducts national VA telehealth exposure classes that address Veteran military exposure concerns and sees Veterans who have complex military environmental exposure concerns through WRIISC’s clinical programs.  She has been involved in many VA research projects including serving as a Principal Scientific Investigator for a VA merit grant looking at the impact of acupuncture on Post-Traumatic Stress Disorder (PTSD) sleep difficulties.  Ms. Prisco currently is working with VA and Uniformed Services University of Health Sciences researchers on developing a center that will examine the impact of military exposures across the lifespan.    She has a number of publications in peer-reviewed scientific journals and book chapters.  She works on the WRIISC website developing content for WRIISC programs and the national WRIISC newsletter.  She serves on several joint DoD/VA boards providing subject matter expertise on post-deployment health matters.   Ms. Prisco received her BBA from the University of Notre Dame and her MSN from Yale University.   She is licensed as an adult nurse practitioner.

Contact Ms. Prisco at 202-745-8249.

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Lily Reck, BS
  • Position: Research Assistant

Lily Reck is a Research Assistant with the DC WRIISC’s Complex Exposure Threat Center (CETC). She got her BS in Cognitive Neuroscience from George Washington University (GWU) with minors in Sociology and Psychological & Brain Sciences. Her previous research experience at GWU and the National Institute of Health focused on the impact of cognitive effort on emotion and the neural connections driving feeding behavior in the brain, respectively. Lily strives to apply her knowledge and experience in the brain and behavior sciences to military exposures to best address the health concerns and conditions of Veterans.

Contact Ms. Reck at 202-745-8249.

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Immanuel Samuel, PhD
  • Position: Research Bioengineer

Dr. Samuel is a neuroscientist with the DC WRIISC. He completed Post-Doctoral training and graduated with a PhD in Biomedical Engineering at the University of Florida. His training is in neuro-informatics with exposure to the following: EEG, ECG, Local Field Potentials, Spectral Analysis, Connectivity, biostatistics, MRI (T1, T2, DTI, Functional). His current area of research is in biomedical research, artificial intelligence and neuroscience to examine general health and mental health outcomes for Veterans. He currently oversees studies on the effects of TBI on psychological outcomes, neuroimaging (EEG, ECG, MRI) and other TBI markers. His software development experience has helped develop computerized testing for studies at WRIISC DC. He also leads and collaborates on studies with open datasets and nation-wide big data research (BRAIN study).

Contact Dr. Samuel at 202-745-8249.

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Rachel Stewart, PhD, LICSW
  • Positions:
    • Social Worker
    • Statistical Support

Dr. Rachel Stewart is a Licensed Independent Clinical Social Worker in the District of Columbia. After receiving her BA degree from the University of Notre Dame, Dr. Stewart went on to receive her MSW and PhD from the National Catholic School of Social Service at Catholic University. Dr. Stewart worked for many years in the private sector specializing in serious mental illness in the hospital, residential, and outpatient settings. Since coming to the VA, Dr. Stewart has served primarily in the Emergency Department where she was instrumental in the development and implementation of the Fast Track program. Dr. Stewart is honored to continue learning from her colleagues and the Veteran community at the Washington, DC WRIISC.

Contact Dr. Stewart at 202-745-8000, ext. 54647.

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Angela Summers, PhD
  • Position: Advanced Clinical and Research Fellow

Dr. Summers is a Postdoctoral Fellow in Neuropsychology at the WRIISC-DC. She completed her undergraduate degree from Wake Forest University in Winston-Salem, North Carolina. She obtained her MA and PhD in Clinical Psychology with a Major Area of Study in Neuropsychology from Fordham University in New York City. She completed her Clinical Internship in Adult Psychology with Major Areas of Study in Neuropsychology and Rehabilitation at Rusk Rehabilitation at NYU Langone Health, where she focused on neuropsychological function, cognitive remediation, and psychotherapy with patients following neurological events such as strokes and/or TBI. Her research interests include investigating culture and health disparities as they relate to neuropsychological function, and identification of modifiable lifestyle factors, such as physical activity and diet, that impact brain health. Her clinical interests include taking a holistic approach when working with patients to better identify the intersectionality of biopsychosociocultural factors that may affect a person’s brain health, as well as differential diagnosis in neurodegenerative disorders.

Contact Dr. Summers at 202-745-8000 ext. 56793

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Sherri Tschida, PhD, MA
  • Position: Advanced Fellow in Complex Exposures

Dr. Tschida is a VA Advanced Fellow at the WRIISC-DC and Explosive Ordnance Disposal Veteran. She received her undergraduate degree from American Military University, WV. She completed her MA and PhD in Clinical Psychology with a certificate in Health Psychology at Fielding Graduate University, Santa Barbara, CA. Her dissertation research examined Veterans use of cannabis-based treatments for chronic pain management. Dr. Tschida attended Clinical Internship at Hampton VAMC, Hampton, VA, where she received additional specialized training in Health Psychology with emphasis on chronic pain management, chronic illness and health management, integrated primary care mental health, neuropsychological and psychological assessment, and trauma-focused psychotherapy in a variety of clinical settings. Her current research interests include investigating the effects of hazardous exposures and sub-concussive blast exposures on cognitive functioning, chronic illness, and emotional and physical wellness. Dr. Tschida’s clinical and research interests are motivated by her commitment to improving access to high quality mental health care and rehabilitation services, complimentary and integrative treatment approaches, increasing representation of Women Veterans in research, and increasing health equity for Veterans.

Contact Dr. Tschida at (202) 745-8249

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WenGuo Yao, BS, MS
  • Position: Health Science Specialist / Clinical Coordinator

Mr. Yao holds a bachelor’s degree in biology and a master’s degree in computer science. He plays a key role in coordinating clinical referrals participating in the War Related Illness and Injury Study Center’s National Referral Program.

Contact Mr. Yao at 202-745-8249.

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Harold Yu, BS, MPAS
  • Position: Physician Assistant Program Manager

Harold Yu is a Physician Assistant (PA) and joined the War Related Illness Study Center (WRIISC) in January 2024 after retiring as an Army Lieutenant Colonel with over 28 years of combined service in both the Army and Navy. He most recently served as the Deputy Director of the Department of Operational Medicine (DoOM) at the Medical Center of Excellence (MedCoE) Fort Sam Houston, TX. In the Army he spent 10 out of 15 years deployed or in overseas assignments to include Kuwait, Korea, Djibouti, Kenya, and Iraq. Notable assignments include Deputy Surgeon Area Support Group Kuwait (ASG-K), Battalion Surgeon 168 Multifunctional Medical Battalion (MMB), Senior Medical Officer Camp Simba Kenya, Senior Physician Assistant 4th Brigade, 1st Cavalry Division (Operation New Dawn), 2/12 Cavalry Battalion PA (Operation Iraqi Freedom 2008-2009) and Officer in Charge of the Sergeant Shin Woo Kim Soldier Centered Medical Home, Camp Humphreys Korea. In the Navy he served at the Medical Department Head at Naval Support Facility Thurmont (Camp David) as a member of the White House Medical Unit and Ships Physician Assistant on board the nuclear aircraft carrier, USS Nimitz (CVN 68). Harold received his bachelor’s degree from the University of California, Davis in Psychology and Masters of PA Studies from the University of Nebraska.

Contact Mr. Yu at 202-745-8249.

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