Louis Hagopian, PhD

Louis Hagopian, Ph.D., BCBA-D's picture
Director of the Neurobehavioral Unit, Department of Behavioral Psychology

Kennedy Krieger Institute
707 N. Broadway
Baltimore, MD 21205
Phone: (443) 923-2900
Email: hagopian@kennedykrieger.org

Dr. Louis Hagopian is a research scientist and Program Director of the Neurobehavioral Programs at the Kennedy Krieger Institute. This includes the Neurobehavioral Unit, which provides intensive inpatient treatment for individuals with intellectual disabilities, who exhibit self-injury, aggression, and other problem behavior. He is a Professor in Psychiatry and Behavioral Sciences at the Johns Hopkins University School of Medicine. 

Biographical Sketch: 

Dr. Hagopian received his Ph.D. in Clinical Psychology from Virginia Polytechnic Institute and State University. He completed a pre-doctoral internship at the Kennedy Krieger Institute, and in the Department of Pediatrics at Johns Hopkins University School of Medicine. He is a Board Certified Behavior Analyst, and Licensed Psychologist. Dr. Hagopian’s work involves the integration of clinical service, research, training and advocacy for individuals with intellectual and developmental disabilities. He has consulted with state agencies, education departments, disability service organizations, advocacy organizations, professional organizations, States Attorneys General, and the U.S. Department of Justice for guidance on matters related to persons with autism and intellectual disabilities.  This work includes the development of standards for treatment, position statements, best practice guidelines, and expert consultation.

Research Summary: 

Many children and adults with intellectual disabilities, autism or other neurobehavioral disorders display severe behavior problems such as self-injury, aggression, or property destruction. The Neurobehavioral Unit (NBU) at Kennedy Krieger Institute provides a continuum of care for these individuals that includes a 16-bed inpatient program, outpatient program, and intensive outpatient services. The primary approach used is Applied Behavior Analysis, characterized by the application of principles of behavior derived through laboratory research, the objective measurement of behavior, and the systematic analysis of relations between behavior and environmental events. The NBU draws nationally, and is recognized as the premiere program in the nation for providing intensive behavioral treatment to individuals with severe behavior disorders and developmental disabilities as well as for offering advanced training in applied behavior analysis.

The individuals served on the NBU frequently present rare behavior disorders that require innovative treatment approaches, so the NBU faculty and staff must constantly design new assessment and treatment procedures to meet the varied needs of their patients.
Dr. Hagopian’s clinical research focused on understanding and treating problems related to intellectual and developmental disabilities. The National Institutes of Health have funded his translational research continuously since 2004 (and through to 2018). This research crosses disciplines and seeks to understand the interaction of biological and environmental factors in individuals with intellectual and developmental disabilities. This includes a research grant on behavioral deficits in autism, a neuroimaging study on the reward system in autism, evaluation of generalization of behavioral treatments, and most recently on identifying subtypes of self-injurious behavior.  Dr. Hagopian has published his research in over 20 different peer-reviewed behavioral, medical, and psychiatric journals, including: the Journal of Applied Behavior Analysis, Journal of Child Neurology, Journal of Developmental and Physical Disabilities, American Journal on Mental Retardation, Behavior Therapy, Journal of Anxiety Disorders, Journal of Behavior Therapy and Experimental Psychiatry, and Pediatrics.

Research Publications:

McGuire K, Fung LK, Hagopian L, Vasa RA, Mahajan R, Bernal P, Silberman AE, Wolfe A, Coury DL, Hardan AY, Veenstra-VanderWeele J, Whitaker AH (2016). Irritability and Problem Behavior in Autism Spectrum Disorder: A Practice Pathway for Pediatric Primary Care. Pediatrics. 137 Suppl 2, S136-48. Abstract
Shirley MD, Frelin L, López JS, Jedlicka A, Dziedzic A, Frank-Crawford MA, Silverman W, Hagopian L, Pevsner J (2016). Copy Number Variants Associated with 14 Cases of Self-Injurious Behavior. PLoS One. 11(3), e0149646. Abstract
Anderson C, Law JK, Daniels A, Rice C, Mandell DS, Hagopian L, Law PA (2012). Occurrence and family impact of elopement in children with autism spectrum disorders. Pediatrics. 130(5), 870-7. Abstract
DeLeon IG, Hagopian LP, Rodriguez-Catter V, Bowman LG, Long ES, Boelter EW (2008). Increasing wearing of prescription glasses in individuals with mental retardation. J Appl Behav Anal. 41(1), 137-42. Abstract

Other Publications:

Hagopian LP, Rooker GW, Jessel J, DeLeon IG. Initial functional analyses outcomes and modifications in pursuit of differentiation: A summary of 176 inpatient cases. J Appl Behav Anal. 2013;46(1);88-100

Hagopian LP, Jennett HK. Behavioral assessment and treatment of anxiety in individuals with intellectual disabilities and autism. J Dev Phys Disabil. 2008;20(5):467-483

Hagopian LP, Bruzak JL, Bowman LG, Jennett HK. Assessment and treatment of problem behavior occasioned by interruption of free operant behavior. J Appl Behav Anal. 2007;40(1): 89-103

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