We are excited to offer this edition of “Seminars in Neurology” focused on Functional Neurological Disorder and thank all the experts who contributed. Some basic review is offered to provide important background for readers. In addition, we have ventured into new areas in FND that the readership should find both interesting and helpful.

We would like to personally thank Dr. David Greer for recognizing the need for neurologists to focus on FND and be updated on how far the field has come. This is critical given how common and costly it is. For example, the annual U.S. inpatient and emergency department charges in 2019 were approximately $2.0 billion, which is an underestimate given the lack of recognition and proper coding for patients with FND. These costs are comparable to or exceed those of other neurological conditions, such as demyelinating disorders, and are similarly debilitating. In recent decades, there has been a growing resurgence of interest in this fascinating disorder. Improving care for patients with FND will require continued education for clinicians, continued research, and funding to truly make a large-scale difference for this common and disabling disorder.

We dedicate this edition of “Seminars in Neurology” to Dr. Mark Hallett. Dr. Hallett was a visionary scientist who recognized the importance for neurologists to understand the brain mechanisms underlying FND to bring the disorder out from the shadows and into mainstream neurology. He received the Founder award for his incredible work in creating, leading, and supporting the International Functional Neurological Disorder Society (2018). His pioneering work in the neurosciences started at the Brigham and Women's Hospital and led him to direct the medical branch of Neurology at the NINDS and the Human Motor Control Section (which he created). His incredible career has inspired a multitude of passionate and brilliant researchers to encourage applying rigorous scientific methods to further improve knowledge, education, and treatments for the large number suffering from FND. His published Wartenberg lecture in 2024, entitled “Functional Neurologic Disorder, ‘La Lésion Dynamique’” highlights the history of FND and his brilliant insights. We are truly in a new dawn for FND.

Article published online:
15 March 2026

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