Going under general anaesthesia is always unnerving. There is this lurking apprehension that you may not emerge out of it.
But anaesthesia could produce some unexpected consequences — something that has caught the fancy of creative writers. For example, in Laughing Gas, PG Wodehouse makes two of his characters — the famous Bertram Wooster and the American child actor Joey Cooley — swap bodies when anaesthetised with nitrous oxide, or ‘laughing gas’, during a dental procedure. Each of their souls gets into the other’s body. What fun!
That is fiction but occasionally reality comes pretty close — as with a 17-year-old Dutch soccer player, who was administered anaesthesia for a knee surgery. The boy woke up alright but no longer remembered his native tongue and only spoke English, a language he had a thin command of. The nurse assumed it was a case of the more common ‘emergence delirium’ but only later did doctors diagnose it as the extremely rare ‘foreign language syndrome’ (FLS). The case has been reported in detail in a 2022 paper titled ‘Lost in another language’.
FLS is extremely rare — only nine reported cases. Another paper, ‘Speaking in tongues’, mentions a 54-year-old Englishman who switched to fluent Spanish after the anaesthesia wore off, and could no longer understand a word of English.
A happy coda to all these cases is that the patients slipped back to their native tongues after a few days — just as Wooster and Cooley went back to themselves. Scientists are saying that the study of FLS could throw light on how languages are stored in the brain.