September 3, 2026

@michaelokun

What resonates with me about Abraham Myerson’s original 1944 description of the glabellar “tap reaction” is how remarkably modern some of his observations feel. He described repeated eye closure “against the will of the patient,” contrasted this with the normal habituation that occurs after several taps to the forehead, and, importantly, recognized that the finding was not confined to Parkinson’s disease. Most strikingly, Myerson reported that the response could occur frequently in what was then called “catatonic dementia precox,” could vary with the severity of the catatonic state, and could even disappear during the same examination as the patient’s clinical state changed. Eight decades later, this observation is an important reminder that neurological signs do not exist in diagnostic silos. In the modern era of Parkinson’s disease, catatonia, functional neurological disorders, and other neuropsychiatric syndromes, we should resist assigning a diagnosis based on a single examination sign. The neurological examination is most powerful when we interpret what we see in the context of the history, associated signs and symptoms, medications, longitudinal course, and the patient’s overall clinical picture. https://jamanetwork.com/journals/archneurpsyc/fullarticle/649901