Dennis Valerstain, MD

Dr. Niles (he/him) holds the position of Staff Psychiatrist at Talkiatry. He has four years of experience in outpatient psychiatry and is board-certified for adult psychiatry. He has received training in the use of cognitive behavioral therapy, supportive therapy, motivational interviewing, psychodynamic therapy, and dialectical behavioral therapy skills. He uses his training in therapy in tandem with medicine management to provide holistic, person-centered care. During his undergraduate studies at the University of Pittsburgh, while completing his pre-medical classes, he also pursued certification in the history and philosophy of medicine. Additionally, he studied the effect of culture and ethics on healthcare. He earned a Bachelor of Science in Psychology with a minor in Chemistry. He attended medical school at the West Virginia School of Osteopathic Medicine. His psychiatry residency training was completed at Charleston Area Medical Center. While in residency, he worked to improve cultural awareness in the outpatient setting. Dr. Niles is interested in treating patients with a wide variety of diagnoses. He treats mood disorders, anxiety disorders, trauma-related disorders, personality disorders, OCD, comorbid addiction, mild eating disorders, neurodevelopmental disorders such as autism spectrum disorder, and more. He also strives to provide care that affirms LGBTQIA+ identities and underwent additional training in transgender mental healthcare.

Dr. Tetyana Tarnavsky is a board-certified psychiatrist trained in Adult Psychiatry. She attended Dnipropetrovsk State Medical Academy in Ukraine where she received her M.D., M.S. and Ph.D. degrees in Psychiatry. Dr. Tarnavsky completed her residency at Harvard South Shore Psychiatry Residency Training Program in MA, where she was elected chief resident. Dr. Tarnavsky has an extensive research experience in Ukraine and the USA. She had studied computer addiction for her dissertation; had multiple abstracts and presentations; published several articles in peer-reviewed psychiatric journals as well as a book entitled Computer Addiction: Formation, Diagnosis, Correction and Prophylaxis. She has helped organize international conferences with the goal of improving access to and quality of healthcare in Dnipropetrovsk, Ukraine, and providing a national model for health care reform. Dr. Tarnavsky has worked with a variety of patients with diverse backgrounds in a Community Health Center and in the Partial Hospitalization Program as well as supervised medical students, psychiatry residents, and nurse practitioners. She has been a lecturer on psychiatry at Harvard Medical School and was involved in the training of psychiatry residents in the Harvard South Shore Psychiatry Training Program. Her primary focus has been on treating adults with depression, anxiety, post traumatic stress disorder, adjustment disorder, ADHD and other disorders. Dr. Tarnavsky strives to provide quality and compassionate treatment to individuals and their families.‍

Dr. Bryant graduated from Mount Sinai School of Medicine to complete her adult training and the Yale Child Study Center/Riverview Hospital for Children Program to complete her fellowship in Child and Adolescent Psychiatry. A native Texan, she returned to Tyler, TX in 2020 to accept the position of Chair of the Department of Psychiatry and Behavioral Medicine at the University of Texas Health Science Center at Tyler. She also established an accredited child and adolescent psychiatry fellowship in Tyler. Prior to that, she served as the Director of the Child and Adolescent Psychiatry Division at the University of Mississippi Medical Center where she was also the Program Director of the Child and Adolescent Psychiatry Fellowship. She received her medical degree from the University of Texas Southwestern Medical School. Working with survivors of trauma has always been an important part of Dr. Bryant's practice. She currently serves as the co-chair of the American Academy of Child and Adolescent Psychiatry's Committee on Child Maltreatment and Violence and she is a representative for the National Health Collaborative on Violence and Abuse. Dr. Bryant also served as the program director of the Eating Disorders and Trauma Recovery program at Menninger Clinic in Topeka. She is board certified in adult, child and adolescent psychiatry and she has over 32 years of experience as a practicing psychiatrist. Dr. Bryant specializes in the treatment of anxiety disorders, obsessive-compulsive disorder, mood disorders, developmental disorders, Post-Traumatic Stress Disorder, Attention Deficit Hyperactivity Disorder, and family relational problems for both children and adults. She believes that "knowledge is power" and that the more a person can understand about how the brain is affected by various mental health conditions, the more treatment makes sense.

Dr. Fisher is a psychiatrist with over 20 years of experience in adult psychiatry, military health, addiction medicine, business leadership, and executive consultation.  His background has given him the opportunity to work with a diverse range of individuals, and he brings that breadth of experience to every patient relationship. In addition to his medical training, Dr. Fisher completed advanced training in psychodynamic and person-centered psychotherapy, which helps him provide care that’s not only evidence-based, but also deeply respectful of each person’s unique story.

Patients often describe Dr. Fisher as easygoing, kind, and patient. He takes pride in being someone who truly listens. he strives to create a safe, nonjudgmental space where you can be yourself—no matter where you're starting from. His goal is to meet you where you are, both emotionally and practically, and help you move toward where you want to be.

Dr. Fisher's approach is collaborative and flexible. He begins by getting to know you—your history, your concerns, and your goals. From there, we work together to create a treatment plan that may include therapy, medication, or both, depending on what’s appropriate for your needs. He integrate both psychodynamic insight and person-centered techniques, always with an emphasis on mutual respect and open communication. Progress takes time, and he's here to support you every step of the way.

Jaime Sather, PMHNP is a board certified psychiatric nurse practitioner with over 20 years' experience in the mental health field. Specialty areas include ADHD, anxiety, depression, mood disorders, substance abuse, PTSD, and women’s health. Clinical experience with inpatient, outpatient, detoxifications rehab, psychiatric emergency department, IOP, and PHP.

Comprehensive psychiatric evaluations, medication management, and brief psychotherapy are provided. Besides medication management with psychotherapy, individual therapy may be recommended for the best possible patient outcome.

Patients feel comfortable discussing their concerns in a non-judgmental therapeutic environment. Education is provided about diagnosis and treatment options with the patient being empowered to be an active part of their treatment plan.

Thomas Ittoop, MD has experience practicing in both academic and community settings. He earned his medical degree from Central Michigan University and completed his psychiatry residency at Baylor College of Medicine. His background reflects a commitment to comprehensive, patient-centered care grounded in clinical rigor and human understanding.

Dr. Ittoop fosters a warm, collaborative environment rooted in genuine human connection. He values uncovering core patterns, meaning, and the story beneath symptoms. His approach emphasizes curiosity, emotional insight, and self-understanding. Patients can expect transparency, clear communication, and shared goal-setting that honors their strengths, long-term vision, and capacity for resilience and wholeness.

He begins with a thorough initial evaluation exploring symptoms, personal and family history, personality patterns, and desired life changes. Together, he and his patients identify core goals and develop a personalized treatment plan. His integrative therapeutic style includes thoughtful medication management, regular check-ins, and a focus on long-term transformation—building clarity, resilience, and a grounded sense of self that extends beyond treatment.