Our behavioral and rehabilitation psychologists and neuropsychologists—experts in brain functioning—are integral members of our interdisciplinary clinical teams, and are fundamental to the assessment and personalized plan development for each patient. They understand how the structure and function of the brain relates to specific psychological processes, like memory, critical thinking and judgment, and how those processes may affect behavior.

They guide the assessment of progress, making sure each team member keeps the whole person in mind – including his or her interests, profession or work history, and hobbies—and adjusts the treatment plan for individual needs so that the person can thrive in the real world.


Melissa Dillon, Ph.D.

Melissa_DillonDr. Dillon is a licensed psychologist with training and experience in neuropsychology and rehabilitation at our Brinlee Creek Ranch location.  She completed her Ph.D. in Clinical Medical Psychology from the University of Alabama at Birmingham in 1998.  Her focus on neuropsychology and rehabilitation psychology began during her graduate training and has continued since in a variety of clinical settings. Dr. Dillon’s clinical and research interests include neuropsychological assessment, rehabilitation of neurological disorders, behavioral interventions, memory, attention, outcomes, and psychiatric comorbidities.


“I find joy working at Pate Rehabilitation and being a part of helping others regain their lives.”


Mary Ellen Hayden, Ph.D., ABPP

Dr. Hayden completed her Ph.D. in Psychology with a specialty in neural substrates of cognition and behavior at the University of Houston in 1976. Dr. Hayden then completed her post-doctoral training with a focus on neuropsychological assessment, planning of rehabilitation of neurologically impaired individuals and research involving hearing impaired and/or language/learning disabled individuals in 1979 at the University of Texas Health Science Center. Dr. Hayden is the founder of Pate Rehabilitation and works with our experienced Pate professionals to continually develop and use up-to-date evidence-based treatment, increase individualization of patient treatments, explore ways to bring family members’ participation in the treatment programs, and use Pate’s extensive database research to continue development of greater effectiveness and efficiency.


“I work at Pate because our staff provides A+ treatment for all our patients—just as I would have required for my son, Ben, had he lived past his brain injury.”


Carlos Marquez de la Plata, Ph.D.

Carlos Marquez de la Plata, Ph.D.

Dr. Marquez is a licensed Psychologist in the state of Texas.  He obtained his Ph.D. in Clinical Psychology at the University of Texas Southwestern Medical Center in 2005.  He completed postdoctoral training in Research Neuropsychology at the University of Texas Southwestern Medical Center in 2007.  Dr. Marquez de la Plata’s research focuses primarily on identifying and ultimately improving neurocognitive and functional impairments related to various brain illnesses such as Traumatic Brain Injury (TBI) and Alzheimer’s disease. Additionally, as a Spanish-speaking neuropsychologist, Dr. Marquez de la Plata is interested in developing neurocognitive measures appropriate for Spanish speakers.


“It is an exciting time to be at Pate!  I am able to combine my love of research and technology with daily patient and family contact that allows me to see the incredible work that we do here.  As a Spanish-speaking neuropsychologist, I am part of Pate’s groundbreaking Spanish-language brain injury rehabilitation program.”


Matt Mordhorst, Ph.D.

Dr. Mordhorst is a licensed Psychologist in the state of Texas.  He obtained his Ph.D. in Counseling Psychology at the University of Iowa in 2003.  He completed postdoctoral training in Clinical and Research Neuropsychology at the University of Michigan in 2005.  Dr. Mordhorst worked as a Psychologist at OSF Saint Francis Hospital, a Level 1 Trauma Center with both acute and post-acute rehabilitation programs before coming to Pate in 2011.



“The satisfaction from helping patients with brain injuries and their families understand their condition and improve their lives is immeasurable.  It really reaffirms my faith in the strength and tenacity of the human spirit.”


Kathryn Oden, Ph.D.

Dr. Oden is a licensed psychologist with a degree in Clinical Neuropsychology from the University of Houston.  As a Master’s level clinician, she worked in State Schools and County agencies with children and young adults who had mental retardation as well as in the State Prison Psychiatric Hospital with individuals who had severe psychiatric problems.  After she completed her Ph.D. in 1997, Dr. Oden worked in brain injury rehabilitation and private practice settings. For the past 10 years she has been the Director of Pate Rehabilitation’s Assessment Department, offering patients her expertise in understanding the effects of various neurological injuries and diseases on everyday cognitive functions like attention, language and memory. Dr. Oden is published in neuropsychological assessment, effectiveness of rehabilitation in stroke patients, learning disability related to genetic neuropsychological disorder, patient awareness of changes from brain injuries and physiological manifestations of psychiatric disease.

“I believe everyone is valuable no matter what problems he or she may be dealing with. Helping someone regain the kind of life they are happy to live as well as recognizing and achieving realistic goals is magical to me.”


Pat Plenger, Ph.D., ABPP

A board-certified clinical neuropsychologist, Dr. Plenger has more than 30 years’ experience in assessments, treatments and directing brain injury rehabilitation programs. He has also presented numerous presentations on brain injury recovery and treatment. Dr. Plenger is currently collaborating on research with other institutions such as University of Texas Arlington, University of Texas Dallas and University of Texas Southwestern. In addition, he is leading research on brain functioning and recovery using functional near infrared spectroscopy (fNIRS) at Pate.



“Working at Pate Rehabilitation allows me to bring together two of my greatest passions: understanding how the brain functions and helping people who are in need. I have been fortunate to pursue these passions in the brain rehabilitation industry for the past 30 years, 21 of which have been with Pate.”


Dawn Toudouze, Ph.D., ABPP

Dr. Toudouze is a licensed psychologist and Board Certified in Rehabilitation Psychology. She specializes in the practice of Neurorehabilitation Psychology. She completed her Ph.D. in Clinical Psychology from Seattle Pacific University in 2006, and has been working in post-acute neurorehabilitation ever since. Dr. Toudouze’s clinical and research interests include evidence based cognitive rehabilitation and neuroplasticity.



“My greatest professional joy is watching people accomplish, in rehab,  what they did not think was possible.”


Marlene Vega, Psy.D.

Marlene-Vega-with-backdropDr. Marlene Vega is a bilingual licensed psychologist specialized in rehabilitation neuropsychology and cross-cultural psychology. She earned a doctoral degree in clinical psychology from the Minnesota School of Professional Psychology in 2013. She completed a pre-doctoral internship in neuropsychology and behavioral health in 2013 at Lancaster General Hospital – University of Pennsylvania Health System, and a postdoctoral fellowship in rehabilitation and neuropsychology at Rancho Los Amigos National Rehabilitation Center in 2014. She is a member of the National Academy of Neuropsychology (NAN), American Congress of Rehabilitation Medicine (ACRM) and American Psychological Association (APA), and holds various leadership positions in the APA Division of Rehabilitation Psychology. Her professional interests include health promotion, psychological adjustment after illness and disability, rehabilitation team models, cross-cultural factors in health and disability, bilingual neuropsychology, and international rehabilitation medicine.

“Each day is an exciting opportunity to make a difference and discover hope.”