A good joke was enough to knock one healthy man unconscious, and it kept happening for 17 years. When the 42-year-old finally reached a neurology clinic, his doctors noticed a detail that made the case stand out: he passed out after spontaneous, unrestrained laughter, but never when he laughed on purpose.
The case, reported by neurologists Athanasios Gaitatzis and Axel Petzold in The Neurologist in 2012, was diagnosed as recurrent laughter-induced syncope, also called gelastic syncope. The authors warned that doctors may not recognize laughter as a cause of fainting, which can lead to misdiagnosis or tests patients never needed.
