INVESTIGATORS

Alka Khera, MD

NEUROLOGIST, PRINCIPAL INVESTIGATOR

  • Meet Dr. Khera!

    Dr. Khera received her MD degree from Wayne State University in Detroit, MI and completed her neurology residency at the University of Texas Southwestern Medical Center in Dallas (UTSW).  She then obtained further training in Behavioral Neurology & Neuropsychiatry. 


    Her mother was diagnosed with frontotemporal dementia in 2007 so she has seen the devastation that a neurodegenerative condition can wreak on a family.  She has joined Kerwin Medical Center in order to expand her reach in clinical research and, not only find a cure for Alzheimer’s Disease and Related Dementias (ADRD), but also to find more resources for care partners of dementia patients. 


    Outside of work, she likes to spend time with her husband, Thom, and their two fur babies, a dog named Mocha and a cat named Earl Grey.  She loves trying new restaurants, doing yoga, and going to concerts.  


     

Zaid Shah, DO

INTERNIST, PRINCIPAL INVESTIGATOR

  • Meet Dr. Shah!

    Stay tuned to meet Dr. Shah!

Diana Kerwin, MD, CPI

INVESTIGATOR

  • Meet Dr. Kerwin!

    Click here to meet Dr. Kerwin!

Subhan Tabba, MD, MBA

INTERNIST, INVESTIGATOR

  • Meet Dr. Tabba!

    Dr. Subhan Tabba is an Academic Hospitalist at Texas Health Presbyterian Dallas Hospital and has joined Kerwin Medical Center to further his work in Alzheimer’s Disease and Related Dementias (ADRD) research. His focus is not only on finding a cure for these conditions but also on providing more resources for the care partners of dementia patients.


    Dr. Tabba earned his Medical Doctorate (MD) from The University of Texas Health Science Center at McGovern Medical School and a Master of Business Administration (MBA) from the University of Houston. He also holds a Bachelor of Science in Cell and Molecular Biology and a Bachelor of Arts in Psychology from The University of Texas at Austin.


    A first-generation Pakistani-American, Dr. Tabba is deeply committed to advancing public health and healthcare for marginalized communities. His leadership and advocacy have reshaped policies at local, state, and national levels since 2018. His work has earned him several prestigious accolades, including the National Minority Quality Forum’s 40 Under 40, the Mark Feldman Academic Excellence Award, the Texas American College of Physicians Early Career Physician Award, and the University of Houston Alumni Association Early Achievement Award.


    At Kerwin Medical Center, Dr. Tabba continues his mission to drive meaningful progress in dementia research, offering hope to patients and their families. When not working, he enjoys spending time with loved ones, traveling, and playing pickleball.


COGNITIVE ASSESSMENT

Tiffini Hansen

MANAGER OF COGNITIVE RATER SERVICES

  • Meet Tiffini!

    Tiffini Hansen is a graduate from the University of California Polytechnic in San Luis Obispo, California where she earned a degree in psychology. Tiffini has been a psychometrist for over 10 years, with a focus on geriatrics. Tiffini has been married for 23 years and has two teenage boys who are heavily involved in baseball, so she spends most of her time at baseball fields on the weekend. Being part of a research team with so much heart and soul has been a blessing to her.   

Jim Harris, PsyD

NEUROPSYCHOLOGIST, COGNITIVE RATER

  • Meet Dr. Harris!

    Dr. Jim Harris earned a doctorate in clinical psychology from Baylor University, with internship at the University of Texas Southwestern Medical School.  He conducts neuropsychological assessments, and has done dementia research seeking to promote effective treatment for Alzheimer’s disease since 2013.  He is published in peer-reviewed journals.  He provided neuropsychological services for Presbyterian Hospital of Dallas, and founded the Memory Clinic of Texas specializing in dementia assessment.  He became a member of the National Academy of Neuropsychology in 2003.  He has enjoyed serving as clinical faculty for the UTSW Medical School and Southern Methodist University directing doctoral students in their clinical work. 

Maddie Liggett, MPH

COGNITIVE RATER

  • Meet Maddie!

    Maddie joined KMC in 2023 as Practice Manager, and has transitioned into a Cognitive Rater role. She has a Bachelor of Arts in Psychology from Texas A&M and a Master of Public Health specializing in Health Policy and Management from Johns Hopkins. 


    Prior to joining KMC Maddie worked in process improvement and operations in a wide variety of settings, including patient access, a fully remote healthcare startup, and a robotic bariatric surgery clinic. She is excited to combine her passion for efficient and equitable healthcare with her passion for neuroscience and psychology in her role at KMC.


    Outside of the office, Maddie can usually be found crocheting, trying new restaurants, and finding any excuse to take a nap.


Diana Mauricio, MS

COGNITIVE RATER

  • Meet Diana!

    Stay tuned to meet Diana!

PHARMACY AND LAB

Caitlin Feeley, PharmD

RESEARCH PHARMACIST

  • Meet Caitlin!

    In 2021, Caitlin achieved her Doctor of Pharmacy and Master of Science from Regis University School of Pharmacy in Denver, CO. She practiced as a Pharmacy Manager specializing in Medication Therapy Management in Ohio and Kentucky before moving to Texas to be closer to family. Caitlin has been passionate about clinical research since working as a research associate in pharmacy school, where she contributed to investigations in immunology and pharmacogenomics. She has been recognized for her leadership acumen by the American Pharmacists Association and the Pharmacy Leadership Society. 


    As a research pharmacist with KMC, Caitlin is excited to utilize her passion for research and patient care to contribute to finding a cure for Alzheimer’s and dementia-related diseases.


    Caitlin is newly married and enjoys exploring everything the Dallas area offers with her husband. In her spare time, she enjoys traveling, cooking new recipes, and spending time with her puppy, Willie!


Tonya Harper, CPhT

PHARMACY TECHNICIAN

  • Meet Tonya!

    Tonya Harper is a highly experienced Clinical Research Pharmacy Technician with over 30 years in pharmacy practice, including more than 25 years specializing in sterile compounding. Originally from West Virginia and now calling Texas home, she is nationally and state certified and sterile compounding certified, with extensive expertise in USP <797> compliance and pharmacy regulations. Tonya is deeply passionate about clinical research, particularly the advancement of treatments for Alzheimer’s disease, driven by the opportunity to contribute to improved patient outcomes and the development of safe, effective therapies.


    She is dedicated to a steadfast commitment to excellence in patient care and fosters a collaborative and positive work environment. Outside of her professional life, Tonya is deeply devoted to her family. She takes great pride in her role as a mother to her son and daughter and finds immense joy in being a grandmother to her twin grandsons, Griffin and Weston. Her family is the foundation of her strength and serves as her daily inspiration, grounding her both personally and professionally.  


Lacey Sands, CPhT

PHARMACY TECHNICIAN

  • Meet Lacey!

    With over 12 years of experience in pharmacy, including 7 years specializing in sterile and non-sterile compounding, Lacey brings a strong foundation of technical expertise and pharmacy regulatory knowledge to the clinical research setting. She has previously held a leadership role with oversight of compounding laboratory operations, with a focus on maintaining compliance.


    Lacey is passionate about contributing to clinical research in Alzheimer’s disease and CNS disorders. This work is especially meaningful to her due to a personal connection, having witnessed the impact of Alzheimer’s disease in her grandmother. This experience continues to motivate her commitment to advancing research that improves patient care and quality of life.


    Outside of work, Lacey enjoys hiking, backpacking, reading and spending time with her two dogs, Luna and Lily. She values any experience that teaches her something new or gets her out in nature.


OPERATIONS

Jordan Caldwell, CCRC

SITE DIRECTOR

  • Meet Jordan!

    Jordan Caldwell joined Kerwin Medical Center in August 2021 as a Certified Clinical Research Coordinator. She came to the role with six years of prior clinical research experience investigating new treatments for a multitude of psychological and neurological conditions. She graduated from the University of Texas at Austin with degrees in both Psychology and Biology.


    Jordan has taken her desire to understand how the brain works to help the team at Kerwin Medical Center find new treatments. Her dedication and hard work show in the care and compassion she gives her patients. Through research and community education she believes that Kerwin Medical Center can make a difference in the fight against Alzheimer’s.


    Jordan is a native Texan from the panhandle. When not at work she enjoys spending time with her husband, traveling, reading, and spoiling her cat.


Karen Aleman, CCRC

PROJECT MANAGER

  • Meet Karen!

    Karen is a happy soul with a big personality. She is passionate about patient care and is always eager to work. She has several years of patient care experience as a medical office assistant, phlebotomist, specimen processor, and clinical researcher.  She earned her associate in science degree from Dallas College in 2020 and her Bachelors of Science in Public Health from the University of Texas at Arlington in 2023. 


    Karen is a Latina woman who is bilingual in both English and Spanish and wants to share her research knowledge with minorities and the Spanish community. She has worked in both inpatient and outpatient care settings, providing patients with the best care out there.


    Karen is happily married with a son and the sweetest dog. In her spare time, she enjoys spending time with her family, watching Korean dramas and stand-up comedy, exploring, and trying delicious new foods.

Megha Chadha, MS, CCRC

PHYSICIAN AND COMMUNITY LIAISON

  • Meet Megha!

    Megha joined Kerwin Medical Center in February 2022 as an intern through her Master’s program in Applied Cognition and Neuroscience at the University of Texas-Dallas. Upon her graduation from her Master’s program in 2022, she joined full-time as a Clinical Research Coordinator. She also graduated in 2021 with a B.S. in Neuroscience from the University of Texas-Austin.


    Megha has always had a passion and interest in neuroscience. She has wanted to be a part of finding a cure since her grandfather passed away from Alzheimer’s Disease when she was young. She feels very strongly about helping patients with dementia, especially underrepresented populations. She wants to use her knowledge in neuroscience to help patients understand the science behind Alzheimer’s. 


    Megha grew up in New Jersey and San Antonio, Texas. In her free time, she loves to attend yoga classes, travel, and be outdoors.

Addy Torres

FRONT OFFICE COORDINATOR - DALLAS PRESBYTERIAN LOCATION

  • Meet Addy!

    As a Front Desk Coordinator, Addy feels fortunate to be the first person patients see when they walk through the door, and she genuinely enjoys creating a welcoming, friendly atmosphere. She finds it incredibly rewarding to be able to interact with our patients, offer support, and engage in meaningful conversations. One of the aspects she loves most about her role is knowing that she's part of a larger team that’s committed to making a difference. Working together toward improving the lives of older adults and their families gives her a real sense of purpose and fulfillment. 


    Outside of work, Addy loves spending time with her family and friends—especially her nephews, who never fail to bring joy and laughter into her world. She also enjoys exploring new restaurants, baking sweet treats for her loved ones, and relaxing with some coloring to unwind and tap into her creativity.


Jocelyn Valdovinos

FRONT OFFICE COORDINATOR - OAK CLIFF LOCATION

  • Meet Jocelyn!

    Stay tuned to meet Jocelyn!

QUALITY ASSURANCE

Kayla Brown, MS

REGULATORY ASSOCIATE

  • Meet Kayla!

    Stay tuned to meet Kayla!

Laurel Nowden, MBA, CCRP

QUALITY ASSURANCE ASSOCIATE

  • Meet Laurel!

    Stay tuned to meet Laurel!

CLINICAL RESEARCH

Maddie Euckert

CLINICAL RESEARCH COORDINATOR II

  • Meet Maddie!

    Maddie is a Clinical Research Coordinator II at Kerwin Medical Center with nearly five years of experience in clinical research across multiple specialties.


    She is driven by the opportunity to contribute to meaningful advancements in Alzheimer’s disease and is passionate about supporting patients and their families throughout the clinical trial journey. Maddie works closely with patients, investigators, and sponsors to help ensure studies are conducted with both precision and compassion. She currently manages multiple trials across two locations, helping translate research into real progress for those affected by neurodegenerative disease.


    Maddie earned her degree in Psychology from Texas A&M University, with a focus in neuroscience and a certificate in Applied Behavioral Health. She began her career at UT Southwestern and has since gained experience in both academic and startup research environments.


    Outside of work, Maddie enjoys concerts, music festivals, and all things beauty, as well as spending time with friends and being near the water whenever she can.


Amarpreet Dhaliwal

CLINICAL RESEARCH COORDINATOR

  • Meet Amarpreet!

    Stay tuned to meet Amarpreet!

Mallory Freeman

CLINICAL RESEARCH COORDINATOR

  • Meet Mallory

    Stay tuned to meet Mallory!

Darah Sanchez

CLINICAL RESEARCH COORDINATOR

  • Meet Darah!

    Darah joined Kerwin Medical Center as a Clinical Research Coordinator supporting the execution of multiple ongoing clinical studies. In this role, she contributes to study coordination, regulatory documentation, and daily research operations in close collaboration with investigators and the research team. Her work includes managing study workflows, maintaining accurate study documentation, and supporting protocol-driven procedures to ensure clinical trials are conducted in compliance with regulatory standards and site processes. 


    She is committed to maintaining high standards of organization, reliability, and operational consistency within the research program. 


    Outside of work, Darah enjoys staying active, reading, and spending time with loved ones.

Roberto Moreno

CLINICAL RESEARCH COORDINATOR

  • Meet Roberto!

    Roberto earned his Bachelor’s degree in Biology from the University of Texas at Dallas and is currently pursuing a Master’s degree at the University of Texas at Arlington. He has a strong background in cancer research, beginning his career studying the effects of heme sequestration in non-squamous non-small cell lung cancer (nsq-NSCLC). He subsequently contributed to early-phase oncology research, conducting first-in-human studies of multiple Phase 1 investigational agents targeting a spectrum of advanced solid tumors, including colorectal cancer, non-small cell lung cancer, melanoma, pancreatic cancer, and rare solid tumors. In 2026, he joined Kerwin Medical Center to focus on Alzheimer’s research, bringing his expertise in translational science and early drug development to neurodegenerative disease studies.


    Outside of research, Roberto enjoys spending time with his wife, whether outdoors camping, exploring new restaurants and cuisines, or watching a football game. He also appreciates indoor activities and discovering new experiences. He balances his professional work with a love for adventure, good food, and football.


Ashna Adhikari

CLINICAL RESEARCH COORDINATOR

  • Meet Ashna!

    I’m Ashna and I’m a graduate from the University of Texas at Dallas with a Master’s in Applied Cognition and Neuroscience. Upon graduation from the Master’s program in 2023, I continued to work at the University of Texas at Dallas doing research on the impacts of TBIs and MS on verbal retrieval. Eventually I want to earn my PhD in Clinical Neuropsychology, because I love research and want it to be accessible to everyone. It’s with this in mind that I joined Kerwin Medical Center, I want as much exposure to different populations as I can get, so that I know where I can help. 


    In my free time I enjoy having an active social life, hanging out with my family, and going to as many events as Dallas has to offer. 


Gabi Mireles

RESEARCH ASSISTANT

  • Meet Gabi!

    Gabi joined the KMC team in October of 2024. Here's what she has to say: 


    I genuinely enjoy being part of a team that makes a difference in people’s lives. With years of experience working with the older community, I’ve developed a strong passion for providing support and creating meaningful connections. One of my favorite aspects of my role is the opportunity to interact with patients face-to-face, ensuring they feel comfortable and cared for.


    As a natural people person, I thrive on building relationships and making every individual feel heard and valued. Whether I’m assisting patients or collaborating with colleagues, I love fostering a positive, welcoming environment. For me, it’s all about making a real impact and improving the patient experience every step of the way.