Mahlon DeLong

DELONG, Dr. Mahlon

Mahlon Robert DeLong, M.D., passed away peacefully at home on May 17, 2024, at the age of 86, with his loving family around him. His medical career spanned over 50 years with notable achievements that contributed to foundational science, pioneering treatments and research for the challenging diseases of Parkinson's, Dystonia, and other movement disorders, and decades of patient care. He was known for his humility, generosity, caring nature, and intense interests across a wide and diverse spectrum of topics, which he shared freely with all those around him.

Mahlon was born in 1938, in Des Moines, IA, and spent his early childhood there and in Kansas. He soon headed west to Balboa Island in Newport Beach, CA, where he attended the Newport Harbor Union High School, beginning his life-long love for swimming in and being near the ocean. He graduated cum laude from Stanford University in 1961, during which he spent a year abroad at the Free University of Berlin, Germany. After a year in graduate school at Stanford University, he then traveled east and graduated cum laude from Harvard Medical School in 1966.

After finishing an internship and the first year of his residency at Boston City Hospital in 1968, he moved south to work at the National Institutes of Health in Bethesda, MD. There he was a Research Associate at the Laboratory of Clinical Science, serving as part of the Reserve Corps in the U.S. Public Health Service. He continued as a Staff Fellow in the Laboratories of Clinical Science and Neurophysiology, where he began his life-long passion for and focus on movement disorders, specifically focused on parts of the brain called the basal ganglia.

At the time, while it was known that the basal ganglia were generally involved in movement, there was little known about the specifics. Mahlon and colleagues significantly advanced the knowledge about how circuits and networks related to the basal ganglia interacted with the rest of the brain and movement.

He then moved to Baltimore, MD, where, after completing his residency in Neurology in 1976, he joined the faculty of Johns Hopkins Hospital and School of Medicine. He became a full professor of Neurology and Neuroscience in 1986. During this time, he led intense and deep research into the basal ganglia and the associated brain circuits involved in movement, emotions, and cognition.

In 1990, Mahlon was recruited by Emory University to serve as the Chair of the growing Neurology Department and served in that capacity until 2003. Under his leadership, the Department grew substantially, both in size and national and international impact. Among his many accomplishments, he and his team refined a ground-breaking neurosurgical procedure that brought profound relief to patients suffering from the debilitating symptoms of Parkinson's disease.

Mahlon was elected to the National Academy of Medicine in 2004 and the American Academy of the Arts and Sciences in 2009. In 2014, he received the Breakthrough Prize in Life Sciences, for his pioneering work in the basal ganglia and his development of a life-changing procedure for those affected by Parkinson's disease. He was likewise recognized for this work, along with his colleague, Dr. Benabid, with the 2014 Lasker-DeBakey Clinical Medical Research Award.

Throughout his career, Mahlon held leadership positions and served on dozens of national and international foundations, associations, and advisory boards, including the American Association for the Advancement of Science, the American Neurological Association, the Society for Neuroscience, the Dystonia Medical Research Foundation, and the American Parkinson Disease Association. He published hundreds of papers and gave hundreds of lectures and symposiums to national and international audiences. He was a mentor to and fostered the career development of a whole generation of neurologists, many of whom have become leaders around the globe.

Mahlon retired in 2019, as Professor Emeritus, and spent time with family and friends, enjoying trips to the shore as he had throughout his life, ranging from the Pacific to the Atlantic — from Nova Scotia to South Carolina, and abroad. He was known for his endless curiosity, his care and love for those around him, and his passion for and love of gardening and dogs, many of whom he rescued throughout his life.

He is survived by his wife, Mary DeLong; his children, Bryan DeLong (Toni), Ariane DeLong (Roger Chalmers), John DeLong (Melissa), and Laura Aspey (Stuart). He was Grandpa to Sarah, Sam, Alex, Zack, Ella, Rosie, Will, Mary, and Abigail. He was also brother, uncle, cousin, and relative to many and an "adopted father" to a key few – always willing to help those in need around him. His concern for others, willingness to listen, and calm nature will be deeply missed.

There will be a celebration of life at a later date. Mahlon was closely involved with a number of organizations, including the Emory University Parkinson's Disease and Movement Disorder Center, the Dystonia Medical Research Foundation, and the American Parkinson Disease Association. A tribute in his memory can be made with a donation in his name to one or more of these organizations, or another of your choice.