After a stroke, a 64-year-old woman in Germany could barely move her face when doctors asked her to. When she laughed, the weakness faded. For her neurologists, that mismatch confirmed a rare diagnosis. It also shows something most people never notice: the brain controls a deliberate smile and a genuine laugh through partly separate wiring.
Jonas Ranke and colleagues from the neurology and radiology departments at Martin-Luther-University Halle-Wittenberg described the case in a letter in Neurological Sciences, published online May 14, 2026. They diagnosed Foix-Chavany-Marie syndrome, a rare paralysis of the face, tongue, throat, and chewing muscles. The authors note that most of the nearly 200 reported cases were caused by strokes affecting the same brain region on both sides. In this patient, that two-sided damage came from strokes that happened years apart.
