Teen boy wakes up from knee surgery speaking only foreign language, refuses to recognise parents. Here’s what doctors found

A surprising case came in the Netherlands when a teenage boy woke up from a routine knee surgery and was found speaking a foreign language instead of his native language. The 17-year-old boy has Dutch as his native language. He woke up and was found speaking only English, a language he primarily used in school. Initially, the staff at the hospital where he was admitted assumed it was a behaviour that would pass in a while, but it did not. Later on, the case was documented by doctors and was identified as an instance of foreign language syndrome, an exceptionally rare condition that remains poorly understood.

The boy was in a hospital for a knee surgery after he was injured playing football. The surgery was successful and safe, and there was no immediate complication. But later on, when the boy woke from general anaesthesia, he spoke exclusively in English and repeatedly insisted that he was in the United States.

The boy did not even recognise his parents, and neither was able to speak or understand Dutch, his native language. According to the medical report, he had no prior psychiatric history and no relevant family medical history, apart from instances of depression on his mother’s side. Doctors diagnosed the teenager with foreign language syndrome (FLS), a condition in which patients suddenly and involuntarily switch to speaking a second language instead of their native one.