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Division of Intramural Research

Clinical Investigations Branch


The Clinical Investigations Branch (CIB) in the National Center for Complementary and Integrative Health (NCCIH) Intramural Research Program promotes high quality mechanistic clinical research targeted at understanding pain, its development, maintenance, and transition to chronic pain. The CIB provides a clinical setting and the medical expertise to (1) evaluate people with wide-ranging painful disorders and (2) better characterize those factors that contribute to pain and its modulation. Working together, NCCIH clinicians and scientists examine clinical characteristics of painful conditions and their comorbidities and explore the physiological underpinnings of these conditions. CIB research uses sensory physiological testing and structural and functional MRI, in addition to behavioral and psychological testing to understand how cognitive, emotional, environmental and genetic factors influence pain states. In addition, CIB is poised to investigate a diverse range of pain management strategies from behavioral, to noninvasive stimulation, natural products, and novel pharmacological interventions. Overall, CIB research attempts to provide a complete understanding of pain states, and opportunities to develop and test interventions that can effectively manage pain and improve quality of life among those who live with pain. To support these goals, the CIB supports two research sections: the NIH Pain Research Center (PRC) and the Section on Affective Neuroscience and Pain (SANP).

Lab Chief

David Shurtleff, Ph.D.

David Shurtleff, Ph.D., is Deputy Director of the National Center for Complementary and Integrative Health (NCCIH). Dr. Shurtleff is also currently the Acting Scientific Director and Acting Chief for both the Clinical Investigations Branch and the Pain and Integrative Neuroscience Branch, Division of Intramural Research. Read more about Dr. Shurtleff.

Lab Members

Miroslav “Misha” Backonja, MD

Miroslav “Misha” Bačkonja, M.D., Clinical Director and Supervisory Physician

Miroslav “Misha” Bačkonja, M.D., is clinical director of the Division of Intramural Research at the National Center for Complementary and Integrative Health (NCCIH). He also serves as supervisory physician in the Clinical Investigations Branch, where he is responsible for leading and designing research projects related to assessing pain and its underlying biological and neurobiological mechanisms; implementing and developing novel, precise measurements of pain; and coordinating the work of the branch staff. 

Prior to his arrival at NCCIH, Dr. Bačkonja was a professor in the Department of Anesthesiology and Pain Medicine at University of Washington–Seattle. He was also professor of neurology at the University of Wisconsin School of Medicine and Public Health and the University of Wisconsin Pain Treatment and Research Center. He has also served as a research clinician at contract research organizations.

Dr. Bačkonja received his M.D. from the University of Zagreb, Croatia, and completed his neurology residency and pain fellowship at the University of Wisconsin Medical School.  

His clinical and research interests focus on pain and neuroimmunology, including neurological disorders, clinical research, pain mechanisms, psychophysics, and randomized clinical trials evaluating new pharmacologic and nonpharmacologic therapies. 

Dr. Bačkonja’s research has led to the publication of more than 100 peer-reviewed articles, and his pain education efforts have resulted in a series of articles and book chapters, as well as numerous didactic presentations at national and international meetings. He serves as mentor to medical students, residents, clinical fellows, graduate students, and junior faculty. He also has served on editorial boards of several international scientific journals, has been a peer reviewer for the National Institutes of Health and international governmental funding agencies, and is a contributing member of professional societies, governing boards, and committees.  

Dr. Bačkonja can be reached at

Bisi Ayodele, CRNP, Nurse Practitioner

Bisi Ayodele, CRNP, is a nurse practitioner in the Clinical Investigations Branch. She can be reached at or 301-827-0415.

Linda Ellison-Dejewski, CRNP, Senior Nurse Practitioner

Linda Ellison-Dejewski, CRNP, is a senior nurse practitioner in the Clinical Investigations Branch. She can be reached at or 301-594-5731. 

Zahid Noor, Ph.D., Protocol Navigator, Contractor

Zahid Noor, Ph.D., is a protocol navigator in the Clinical Investigations Branch. He can be reached at or 301-480-9912.

Hayley Owens, Clinical Research Coordinator and Sensory Testing Technician

Lab Alumni

Portrait of Dr. M. Catherine Bushnell

M. Catherine Bushnell, Ph.D., NIH Scientist Emeritus

Dr. Bushnell holds a Ph.D. in Experimental Psychology from the American University, Washington, D.C. and received postdoctoral training in neurophysiology at the NIH. She then spent 12 years at the University of Montreal and 16 years as the Harold Griffith Professor of Anesthesia at McGill University before returning to NIH in 2012. She has been president of the Canadian Pain Society, and treasurer and press editor-in-chief of the International Association for the Study of Pain and is currently a councilor for the Society for Neuroscience.

Among her honors are the Lifetime Achievement Award from the Canadian Pain Society and the Frederick Kerr Basic Science Research Award from the American Pain Society. Her research interests include forebrain mechanisms of pain processing, psychological modulation of pain, and neural alternations in chronic pain patients. Read more about Dr. Bushnell.