Louis Hagopian, PhD's picture
Director of the Neurobehavioral Unit, Department of Behavioral Psychology
Phone: 443-923-2900
Kennedy Krieger Institute

707 N. Broadway
Baltimore, MD 21205
United States


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. 


Dr. Hagopian received his PhD 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.


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.

Related Links

Elsevier Fingerprint Engine Profile for Louis Hagopian

Research Publications

Goldberg MC, Allman MJ, Hagopian LP, Triggs MM, Frank-Crawford MA, Mostofsky SHDenckla MBDeLeon IG (2016). Examining the reinforcing value of stimuli within social and non-social contexts in children with and without high-functioning autism. Autism. , .

Hagopian LP, Gregory MK (2016). Behavior analytic approaches to problem behavior in intellectual disabilities. Curr Opin Psychiatry. 29(2), 126-32.

McGuire K, Fung LK, Hagopian L, Vasa RAMahajan 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.

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.

Hagopian LPRooker GWZarcone JR (2015). Delineating subtypes of self-injurious behavior maintained by automatic reinforcement. J Appl Behav Anal. 48(3), 523-43.

Kurtz PF, Chin MD, Robinson AN, O'Connor JT, Hagopian LP (2015). Functional analysis and treatment of problem behavior exhibited by children with fragile X syndrome. Res Dev Disabil. 43-44, 150-66.

Rooker GW, Jessel J, Kurtz PFHagopian LP (2013). Functional communication training with and without alternative reinforcement and punishment: an analysis of 58 applications. J Appl Behav Anal. 46(4), 708-22.

Kurtz PF, Fodstad JC, Huete JMHagopian LP (2013). Caregiver- and staff-conducted functional analysis outcomes: a summary of 52 cases. J Appl Behav Anal. 46(4), 738-49. 

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

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.

Hagopian LPRooker GWRolider NU (2011). Identifying empirically supported treatments for pica in individuals with intellectual disabilities. Res Dev Disabil. 32(6), 2114-20.

Kurtz PF, Boelter EW, Jarmolowicz DP, Chin MD, Hagopian LP (2011). An analysis of functional communication training as an empirically supported treatment for problem behavior displayed by individuals with intellectual disabilities. Res Dev Disabil. 32(6), 2935-42.

Hagopian LP, Kuhn DE, Strother GE (2009). Targeting social skills deficits in an adolescent with pervasive developmental disorder. J Appl Behav Anal. 42(4), 907-11.

Jennett HK, Hagopian LP (2008). Identifying empirically supported treatments for phobic avoidance in individuals with intellectual disabilities. Behav Ther. 39(2), 151-61.

DeLeon IGHagopian 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.

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

Wachtel LE, Hagopian LP (2006). Psychopharmacology and applied behavioral analysis: tandem treatment of severe problem behaviors in intellectual disability and a case series. Isr J Psychiatry Relat Sci. 43(4), 265-74.

Hagopian LPPaclawskyj TR, Kuhn SC (2005). The use of conditional probability analysis to identify a response chain leading to the occurrence of eye poking. Res Dev Disabil. 26(4), 393-7.

Hagopian LP, Kuhn SA, Long ES, Rush KS (2005). Schedule thinning following communication training: using competing stimuli to enhance tolerance to decrements in reinforcer density. J Appl Behav Anal. 38(2), 177-93.

Long ES, Hagopian LPDeleon IG, Marhefka JM, Resau D (2004). Competing stimuli in the treatment of multiply controlled problem behavior during hygiene routines. Res Dev Disabil. 26(1), 57-69.

Hagopian LP, Long ES, Rush KS (2004). Preference assessment procedures for individuals with developmental disabilities. Behav Modif. 28(5), 668-77.

Hagopian LP, Toole LM, Long ES, Bowman LG, Lieving GA (2004). A comparison of dense-to-lean and fixed lean schedules of alternative reinforcement and extinction. J Appl Behav Anal. 37(3), 323-38. 

Hagopian LPCrockett JL, van Stone M, DeLeon IGBowman LG (2000). Effects of noncontingent reinforcement on problem behavior and stimulus engagement: the role of satiation, extinction, and alternative reinforcement. J Appl Behav Anal. 33(4), 433-49.

Hagopian LP, Fisher WW, Sullivan MT, Acquisto J, LeBlanc LA (1998). Effectiveness of functional communication training with and without extinction and punishment: a summary of 21 inpatient cases. J Appl Behav Anal. 31(2), 211-35. 

Hagopian LP, Fisher WW, Legacy SM (1994). Schedule effects of noncontingent reinforcement on attention-maintained destructive behavior in identical quadruplets. J Appl Behav Anal. 27(2), 317-25.

Fisher W, Piazza CC, Bowman LGHagopian LP, Owens JC, Slevin I (1992). A comparison of two approaches for identifying reinforcers for persons with severe and profound disabilities. J Appl Behav Anal. 25(2), 491-8.

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