American dad woke up from surgery fluent in Spanish

A US father has revealed what it's like to have a rare neuropsychiatric condition which left him speaking Spanish after waking up from an operation.

When Utah native Stephen Chase was 19-years-old, he underwent surgery on his right knee after sustaining a football-related injury.

Now, post-surgery recovery can be pretty grim and uncomfortable for people at the best of times, but for Stephen, he was taken by complete surprise to wake up from his operation and be speaking fluent Spanish.

Recalling the bizarre incident, the now 33-year-old explained that his only background with the language was a couple of classes at school and acknowledged that his Spanish skills were 'low level'.

"I did not speak Spanish. I had a year in high school when I'd had a Spanish class," he said.

Utah dad Stephen Chase was shocked after waking up from an operation speaking Spanish (Kennedy News and Media)

"It was really beginner level, it was low level. Maybe I could count to 10 and knew a couple phrases here and there," Stephen continued, noting that didn't 'really pay attention at all' during his lessons.

"I don't really recollect speaking Spanish, just people asking me to speak English and being really confused," he added.

"I wasn't capable of speaking for that long in Spanish at that time, I was very shocked."

So, why had a routine operation turned the father-of-three into a fluent speaker?

This is all due to a rare condition known as Foreign Language Syndrome (FLS).

What is Foreign Language Syndrome?

Also known as Foreign Accent Syndrome, the rare condition is when a person switches from their native accent or language for a period of time before eventually switching back.

The switch is involuntary and sudden, with an affected patient appearing to be fluent in the new language.

According to the National Library of Medicine, FLS can be caused by a number of factors, including brain injury, psychological stress and after a patient wakes up from surgery.

This is due to a rare condition called Foreign Language Syndrome (Kennedy News and Media)

In cases which occur after anesthesia is used, the change can last anywhere between minutes and hours.

The condition is extremely rare, with Cleveland Clinic noting around 100 confirmed cases on record since it was discovered in 1907.

In Stephen's case, he has experienced the phenomena after every surgery he's had and believes his brain's switch to Spanish is down to growing up around Hispanic people.

"I had grown up around lots of Hispanic people and frequently heard the language around me. I spent a lot of time at my best friend's house and his parents were always speaking Spanish," the attorney explained.

"I never knew what anyone was saying but I heard it all the time."