Our Leaders
Marc J. Tassé, PhD
Director, Nisonger Center; Professor, Departments of Psychology and Psychiatry
Marc J. Tassé, PhD, director of the Nisonger Center, conducts administrative duties, performs research and teaches. His research focuses on intellectual disabilities and autism spectrum disorder, and includes an intervention program called Shakespeare and Autism. He has helped develop the diagnostic adaptive behavior scale published by the American Association of Intellectual Developmental Disabilities.
Andrea Witwer, PhD
Director, Training and Community Outreach
Andrea Witwer, PhD, is the Director of Training and Community Outreach at the Nisonger Center and an Assistant Professor of Clinical Psychiatry & Psychology. Dr. Witwer’s current research is focused on meeting the needs of those with autism spectrum disorders (ASD) and other developmental disabilities who present with significant emotional and behavior problems.
L. Eugene Arnold, MD, MEd
Professor Emeritus, Department of Psychiatry; Child and Adolescent Psychiatrist, Nisonger Center
L. Eugene Arnold, MD, MEd, is a child, adolescent and adult psychiatrist. In the Nisonger Neurodevelopmental Psychiatry program, he treats people with developmental disabilities. He specializes in investigating new treatments for attention deficit hyperactivity disorder and autism.
Luc Lecavalier, PhD
Director, Child Behavioral Support Services Program, Nisonger Center/ Professor, Departments of Psychology and Psychiatry
Luc Lecavalier, PhD, serves as the program director of the Nisonger Center Child Behavior Support Services treatment unit, which implements behavior plans for children with developmental disabilities or behavior and emotional problems. He has mentored numerous doctoral candidates and welcomes admitting passionate and hard-working graduate students.
Margaretha Izzo, PhD
Director, Special Education and Transition Program; Associate Director, Nisonger Center
Margaretha Izzo, PhD, serves as program manager of the Special Education and Transition area at the Nisonger Center. Dr. Izzo develops programs to assist high school and college-age students with disabilities find the passion and developmental skills they need to enter careers that are a match for them so that they can become productive members of their community. Providing programs at Ohio State allows Dr. Izzo to help these young adults continue on their path of lifelong learning.
Paula Rabidoux, PhD/CCC - SLP
Associate Director, Nisonger Center; Co-Director, Leadership Education in Neurodevelopmental Disabilities (LEND); Program Manager, Toy and Technology Library
Paula Rabidoux, PhD, is an associate director of the Nisonger Center, co-director of the Leadership Education in Neurodevelopmental Disabilities (LEND) program and program manager of the Toy and Technology Library. She is a speech-language pathologist interested in social language and social communication in children and adults with neurodevelopmental disabilities. She is interested in how parents and children interact to develop social language skills, as well as how young school-age children develop social language and literacy skills.
Susan Havercamp, Ph.D.
Director, Health Promotion and Healthcare Parity, Nisonger Center; Associate Professor, Departments of Psychiatry and Psychology
Susan Havercamp, associate professor of Psychiatry and Psychology, is the director of healthcare promotion and healthcare parity at the Nisonger Center. Havercamp says investigators have found that people with disabilities, compared to those without, have poorer health and a harder time accessing care, so many of her programs work to close this gap.
Betsey Benson, PhD
Director, Adult Behavior Support Services Program; Associate Professor, Clinical Psychiatry and Psychology
Betsey Benson, PhD, recieved her PhD from Northern Illinois University with a clinical psychology concentration. Dr. Benson’s research interests include the study of the mental health needs of adolescents and adults with intellectual disability, autism spectrum disorders and Down syndrome.
Karen Ratliff-Schaub, MD
Director, Clinical Services; Co-Director, LEND Program Nisonger Center; Clinical Assistant Professor, Department of Pediatrics, Nationwide Children’s Hospital
Marilee Martens, PhD
Director, Williams Syndrome Program, Nisonger Center; OSU - Newark, Associate Professor, Department of Psychology
Marilee Martens, PhD, received her PhD in Psychology from the University of Melbourne, Australia, with an emphasis in Neuropsychology. Dr. Martens’ research focuses on Williams syndrome, which is a genetic neurodevelopmental disorder which causes cognitive delay, a hypersociable personality, relative strengths in some aspects of language and music, and significant delays in visuospatial and math abilities.
Michael Aman, PhD
Director of Clinical Trials, Nisonger Center; Director, Research Unit on Pediatric Pharmacology; Professor Emeritus, Department of Psychology
Michael Aman, PhD, is the director of clinical trials at the Nisonger Center. He received his PhD in Psychiatry from the University of Auckland in New Zealand. Dr. Aman’s research interests include child and adolescent drug research on autistic and related disorders, intellectual disabilities, disruptive behavior disorders, and attention-deficit/hyperactivity disorders.
Thomas Fish PhD LISW
Director, Social Work and Family
Tom Fish, PhD, LISW, is the director of Social Work and Family Support Services including community inclusion, adult literacy, social support, and transition for adolescents and young adults with disabilities and their families. Dr. Fish research interests are in the areas of adult literacy, Next Chapter Book Clubs, social programs, Asperger’s Syndrome, Autism Spectrum Disorders, and adult and community support.
Our Researchers
Andrea Witwer, PhD
Director, Training and Community Outreach
Andrea Witwer, PhD, is the Director of Training and Community Outreach at the Nisonger Center and an Assistant Professor of Clinical Psychiatry & Psychology. Dr. Witwer’s current research is focused on meeting the needs of those with autism spectrum disorders (ASD) and other developmental disabilities who present with significant emotional and behavior problems.
Betsey Benson, PhD
Director, Adult Behavior Support Services Program; Associate Professor, Clinical Psychiatry and Psychology
Betsey Benson, PhD, recieved her PhD from Northern Illinois University with a clinical psychology concentration. Dr. Benson’s research interests include the study of the mental health needs of adolescents and adults with intellectual disability, autism spectrum disorders and Down syndrome.
Karen Ratliff-Schaub, MD
Director, Clinical Services; Co-Director, LEND Program Nisonger Center; Clinical Assistant Professor, Department of Pediatrics, Nationwide Children’s Hospital
L. Eugene Arnold, MD, MEd
Professor Emeritus, Department of Psychiatry; Child and Adolescent Psychiatrist, Nisonger Center
L. Eugene Arnold, MD, MEd, is a child, adolescent and adult psychiatrist. In the Nisonger Neurodevelopmental Psychiatry program, he treats people with developmental disabilities. He specializes in investigating new treatments for attention deficit hyperactivity disorder and autism.
Luc Lecavalier, PhD
Director, Child Behavioral Support Services Program, Nisonger Center/ Professor, Departments of Psychology and Psychiatry
Luc Lecavalier, PhD, serves as the program director of the Nisonger Center Child Behavior Support Services treatment unit, which implements behavior plans for children with developmental disabilities or behavior and emotional problems. He has mentored numerous doctoral candidates and welcomes admitting passionate and hard-working graduate students.
Marc J. Tassé, PhD
Director, Nisonger Center; Professor, Departments of Psychology and Psychiatry
Marc J. Tassé, PhD, director of the Nisonger Center, conducts administrative duties, performs research and teaches. His research focuses on intellectual disabilities and autism spectrum disorder, and includes an intervention program called Shakespeare and Autism. He has helped develop the diagnostic adaptive behavior scale published by the American Association of Intellectual Developmental Disabilities.
Margaretha Izzo, PhD
Director, Special Education and Transition Program; Associate Director, Nisonger Center
Margaretha Izzo, PhD, serves as program manager of the Special Education and Transition area at the Nisonger Center. Dr. Izzo develops programs to assist high school and college-age students with disabilities find the passion and developmental skills they need to enter careers that are a match for them so that they can become productive members of their community. Providing programs at Ohio State allows Dr. Izzo to help these young adults continue on their path of lifelong learning.
Marilee Martens, PhD
Director, Williams Syndrome Program, Nisonger Center; OSU - Newark, Associate Professor, Department of Psychology
Marilee Martens, PhD, received her PhD in Psychology from the University of Melbourne, Australia, with an emphasis in Neuropsychology. Dr. Martens’ research focuses on Williams syndrome, which is a genetic neurodevelopmental disorder which causes cognitive delay, a hypersociable personality, relative strengths in some aspects of language and music, and significant delays in visuospatial and math abilities.
Michael Aman, PhD
Director of Clinical Trials, Nisonger Center; Director, Research Unit on Pediatric Pharmacology; Professor Emeritus, Department of Psychology
Michael Aman, PhD, is the director of clinical trials at the Nisonger Center. He received his PhD in Psychiatry from the University of Auckland in New Zealand. Dr. Aman’s research interests include child and adolescent drug research on autistic and related disorders, intellectual disabilities, disruptive behavior disorders, and attention-deficit/hyperactivity disorders.
Paula Rabidoux, PhD/CCC - SLP
Associate Director, Nisonger Center; Co-Director, Leadership Education in Neurodevelopmental Disabilities (LEND); Program Manager, Toy and Technology Library
Paula Rabidoux, PhD, is an associate director of the Nisonger Center, co-director of the Leadership Education in Neurodevelopmental Disabilities (LEND) program and program manager of the Toy and Technology Library. She is a speech-language pathologist interested in social language and social communication in children and adults with neurodevelopmental disabilities. She is interested in how parents and children interact to develop social language skills, as well as how young school-age children develop social language and literacy skills.
Susan Havercamp, Ph.D.
Director, Health Promotion and Healthcare Parity, Nisonger Center; Associate Professor, Departments of Psychiatry and Psychology
Susan Havercamp, associate professor of Psychiatry and Psychology, is the director of healthcare promotion and healthcare parity at the Nisonger Center. Havercamp says investigators have found that people with disabilities, compared to those without, have poorer health and a harder time accessing care, so many of her programs work to close this gap.
Thomas Fish PhD LISW
Director, Social Work and Family
Tom Fish, PhD, LISW, is the director of Social Work and Family Support Services including community inclusion, adult literacy, social support, and transition for adolescents and young adults with disabilities and their families. Dr. Fish research interests are in the areas of adult literacy, Next Chapter Book Clubs, social programs, Asperger’s Syndrome, Autism Spectrum Disorders, and adult and community support.