Psychology Team

Jennifer Katzenstein, Ph.D.

Neuropsychology

Dr. Katzenstein is the director of psychology, neuropsychology and social work, at Johns Hopkins All Children’s Hospital. Previously, Dr. Katzenstein was a private practitioner and Assistant Professor of Neurology at Indiana University School of Medicine/Riley Hospital for Children in Indianapolis where she provided neuropsychological evaluations, consultations and academic coaching for children and adolescents. After graduating from Indiana University Purdue University Indianapolis, she completed a pediatric internship and fellowship at Texas Children's Hospital/Baylor College of Medicine. Dr. Katzenstein is board certified in pediatric neuropsychology and clinical neuropsychology.

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Jennifer Katzenstein

Sakina Butt, Psy.D.

Psychology, Neuropsychology

Dr. Butt is a neuropsychologist at Johns Hopkins All Children’s Hospital. She joined the hospital staff in 2019. Some of Dr. Butt’s areas of clinical expertise include neuropsychological evaluations and consultations for children in the neonatal intensive care unit and pediatric intensive care unit. Dr. Butt earned her medical degree from Florida School of Professional Psychology, Argosy University in Tampa, Florida. After graduating from Argosy, she completed a pediatric internship and fellowship at the University of Miami/Miller School of Medicine. Dr. Butt is board certified in pediatric neuropsychology and clinical neuropsychology.

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Sakina Butt

Melissa Faith, Ph.D.

Psychology

Dr. Faith is a clinical pediatric psychologist specializing in hematology/oncology at Johns Hopkins All Children’s Hospital. She received her master’s and doctorate degrees in clinical psychology from the University of Arkansas, completed a predoctoral internship in clinical child psychology at the University of Mississippi Medical Center and completed a postdoctoral fellowship in clinical psychology with an emphasis in pediatric hematology and oncology at the University of Oklahoma Health Sciences Center. Dr. Faith’s research interests include disseminating evidence-based interventions in large medical and community centers (e.g., motivational interviewing) as well as emotion socialization, social adjustment, and sibling adjustment during and following childhood chronic illness.

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Melissa Faith

Marissa Feldman, Ph.D.

Psychology

Dr. Feldman is a pediatric psychologist in the Johns Hopkins All Children’s Institute for Brain Protection Sciences. She specializes in the evaluation and treatment of children and adolescents with acute and/or chronic medical conditions to promote psychological health and well-being, and provides consultation services on the inpatient units regarding adaptation and coping with illness, treatment adherence, and emotional and behavioral functioning. She joined the hospital staff in 2017. Dr. Feldman received her Doctoral degree in clinical psychology from the University of South Florida, and completed her internship and fellowship at the Ann & Robert H. Lurie Children’s Hospital of Chicago (formerly Children’s Memorial Hospital). Dr. Feldman’s research interests include treatment adherence and quality of life in patients with chronic illness, outcomes of group intervention, psychosocial factors contributing to positive youth development and negative peer relations.

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Marissa Feldman

Alyssa Fritz, Ph.D.

Psychology

Dr. Fritz is a pediatric psychologist in the Johns Hopkins All Children’s Institute for Brain Protection Sciences. She joined the hospital staff in 2018. Dr. Fritz provides evidence-based interventions for pre-school and early childhood disruptive behavior disorders. She also specializes in the evaluation and treatment of children and adolescents diagnosed with chronic and/or acute medical conditions in combination with additional concerns (e.g., anxiety, depression, treatment adherence, phobias) in outpatient settings.

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Alyssa Fritz

William Frye, Ph.D.

Psychology

Dr. Frye is a pediatric psychologist in the Chronic Pain Clinic at Johns Hopkins All Children’s Hospital. He specializes in non-pharmacological treatment for patients with acute and chronic pain conditions and provides skill-based interventions for simultaneous psychosocial concerns. He joined the hospital staff in 2018. Dr. Frye earned his doctoral degree in clinical psychology from Auburn University. He completed a pre-doctoral internship in pediatric psychology at Children’s Mercy Hospitals and Clinics and a postdoctoral fellowship in chronic pain at Nationwide Children’s Hospital. Dr. Frye’s research interests include pain coping and catastrophizing and parental impact on youth outcomes. He is Board Certified in Biofeedback (BCB) by The Association for Applied Psychophysiology and Biofeedback.

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William Frye

Lauren Gardner, Ph.D.

Psychology

Dr. Gardner is the psychology internship director and administrative director of the Autism Program at Johns Hopkins All Children’s Hospital. She has provided services for children and families with a wide range of concerns, including noncompliance, autism spectrum disorder, developmental disabilities, depression, anxiety and social skills deficits. Dr. Gardner’s clinical interests include neurodevelopmental disabilities. She earned her doctorate degree from Indiana University Bloomington and completed an internship in psychology at the University of Tennessee Health Science Center and a fellowship in developmental/behavioral pediatrics at the Boling Center for Developmental Disabilities.

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 Lauren Gardner, PhD PSYCHOLOGY

Callie Gilchrest, Ph.D.

Psychology

Dr. Gilchrest is a pediatric psychologist who specializes in assessment and treatment of autism and other neurodevelopmental disorders. She primarily works in the autism and developmental pediatrics programs on the Johns Hopkins All Children’s Hospital main campus in St. Petersburg, Florida. She joined the hospital staff in 2022.

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Callie Gilchrest, PhD PSYCHOLOGY

Jason Hangauer, Ph.D.

Psychology

Dr. Hangauer is a pediatric outpatient psychologist at Johns Hopkins All Children’s Hospital. He specializes in the evaluation and treatment of autism spectrum disorder (ASD) and developmental disabilities. He joined hospital staff in 2018. Dr. Hangauer's research interests include evidence-based interventions for ASD, behavioral parent training, and assisting allied providers serving children with ASD and other disorders in the use of current research supported best practices.

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Jason Hangauer, PhD PSYCHOLOGY

Colleen Hess, Ph.D.

Psychology

Dr. Hess is a neuropsychologist at Johns Hopkins All Children’s Hospital. She joined the hospital staff in 2021. Her clinical expertise includes neuropsychological evaluations and consultations for children with cancer and brain tumors. Dr. Hess earned her doctoral degree from Florida State University in Tallahassee, Florida. She completed a clinical psychology internship at the University of Florida Health Science Center/Shands Hospital in Gainesville, Florida, followed by a fellowship in clinical psychology at Rothman Center for Pediatric Neuropsychiatry/University of South Florida in St. Petersburg, Florida. Dr. Hess then completed a pediatric neuropsychology fellowship at Johns Hopkins All Children’s Hospital.

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Colleen Hess

Callie King, Ph.D., M.Ed.

Psychology

Dr. King is a pediatric psychologist at Johns Hopkins All Children’s Hospital. She joined the hospital staff in 2023. Dr. King earned her doctoral degree in counseling psychology with a graduate certification in children and adolescents from the University of Northern Colorado in Greeley, Colorado. She completed a doctoral internship as a behavioral health consultant at IU Health Physicians-Tipton Hospital in Tipton, Indiana. She then completed a post-doctoral fellowship in pediatric psychology at Johns Hopkins All Children’s.

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Callie King

Aja Meyer, Ph.D.

Psychology

Dr. Meyer earned her doctorate degree from the University of South Florida, and completed an internship at the Children's Hospital of Michigan and a post-doctoral fellowship at Akron Children's Hospital. Dr. Meyer has provided psychological services to children and adolescents with a broad range of medical conditions, such as diabetes, kidney disease, sickle cell anemia, cancer, and various neurological conditions (e.g., AVM, cerebral palsy, chronic pain, epilepsy, spinal cord injury, stroke, and traumatic brain injury). She provides consultation services on the inpatient units at Johns Hopkins All Children's Hospital and sees outpatients as part of the All Children's Pediatric Psychiatry program.

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Aja Meyer

Stefanie Poehacker, Ph.D., PMH-C

Psychology

Dr. Poehacker is a pediatric psychologist at Johns Hopkins All Children’s Hospital in St. Petersburg, Florida. She joined the hospital staff in 2023. Dr. Poehacker specializes in evidence-based care for families with medically fragile infants including parental coping, parent-infant dyadic interventions, traumatic stress and bereavement, and neurodevelopmental intervention and assessment. She closely collaborates with multidisciplinary teams in the intensive care setting to provide family-centered, trauma-informed care to support family functioning and infant development.

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Stefanie Poehacker PhD

Ally Schimmel-Bristow, Ph.D.

Psychology

Dr. Schimmel-Bristow is a pediatric psychologist at Johns Hopkins All Children’s Hospital in St. Petersburg, Florida. She joined the hospital staff in 2023. She earned her doctoral degree in counseling psychology from the University of Memphis, completed a predoctoral internship with an emphasis in adolescent and adult clinical health psychology at Medical College of Georgia, and completed a research and clinical postdoctoral fellowship with an emphasis in pediatric hematology, oncology and bone marrow transplant at Johns Hopkins All Children’s.

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Ally Schimmel-Bristow

Sarah Sobalvarro, Ph.D.

Neuropsychology

Dr. Sobalvarro is a pediatric psychologist in the Johns Hopkins All Children’s Institute for Brain Protection Sciences. She joined the hospital staff in 2019. In her role, Dr. Sobalvarro sees patients in the weight management and eating disorder clinics and provides weekly therapy for patients with disordered eating, body dissatisfaction, weight management concerns and psychological conditions.

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Sarah Sobalvarro, PhD

Nora Coultis, Ph.D.

Neuropsychology Fellow

Nora Coultis

Emily Foard, Psy.D.

Neuropsychology Fellow

Emily Foard

Lauren Irwin Harper, Ph.D.

Neuropsychology Fellow

Lauren Irwin Harper

Megan Millmann, Psy.D.

Psychology Fellow

Emily Millmann

Katrina Obleada, Ph.D.

Psychology Fellow

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