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Go to CuriosityStream.com/psych to learn more. [ ♪ INTRO ]. Whether you're creating the perfect voice for your next RPG character, or doing it just for fun, it can be pretty amusing to put on a different accent sometimes.

But what if you didn't have a choice? What if one day, your accent totally changed to one from a place you've never lived? And try as you might, you couldn't change it back?

This condition is known as foreign accent syndrome, and it's incredibly rare, but it can result from certain brain injuries or conditions. A classic case of foreign accent syndrome was described by a Norwegian neurologist in 1947, and involved a Norwegian woman known as Astrid who appeared to develop a German accent. In 1941, Astrid was injured by shrapnel to the head during an air raid.

Her doctor noted that Astrid didn't start speaking German; her native Norwegian accent had changed to something that sounded German. Astrid was experiencing a phenomenon called dysprosody. Parts of her speech delivery such as intonation, rhythm, and the “em-PHA-sis of each sy-LLA-ble” were different from those used in Norwegian, but the content of her speech didn't change.

Her doctor also noted that the new accent actually sounded like a mix of French and. German; further analysis of her speech patterns showed that it was a change in certain tonal features, not a bona fide foreign accent. The reason it sounded like one is that it takes two to tango.

The patient starts speaking differently after brain trauma… and the people listening relate that change to something they're familiar with. This phenomenon is known as pareidolia, where we interpret vague information as being something we recognize. Like seeing a bunny in the clouds or a butterfly on an ink blot, people were interpreting Astrid's new speech pattern as a specific accent — even though her doctor's observations suggested it wasn't really.

So what's the problem? If Vikings that train dragons can sound Scottish, does it matter if Astrid sounded German? Well, when medical professionals think about how to treat a patient, a big factor is whether that person's daily life is affected by their condition.

And this new accent impacted Astrid's life in a big way. She was a Norwegian who sounded German during the German occupation of Norway at the height of World War II. Given the isolation this caused her, it's pretty clear that she wasn't just putting on a fake accent for fun.

Now, there are a few different ways foreign accent syndrome can develop. These can include brain damage or disorders: for example, it can be seen in the aftermath of a stroke, or more chronic diseases like multiple sclerosis. Some people may even experience foreign accent syndrome off and on in conjunction with severe migraines.

Your unique way of speaking is the result of an intricate web of pathways that connect all over your brain. When these are damaged, the unusual speech delivery heard in foreign accent syndrome can result. For example, Broca's Area is a region of the brain usually in the left frontal lobe that plays a major role in speech production.

Damage to this region can result in slurring or stuttering, and can also result in changes in the melody of speech similar to those in foreign accent syndrome, especially after a stroke. But not everyone diagnosed with foreign accent syndrome has a specific brain lesion. Sometimes the causes can be psychological instead, related to conditions like bipolar disorders.

In at least one such case reported in 2007, brain imaging showed decreased activity in large areas of the brain that include speech. That decreased activity corresponded with roadblocks to speech delivery. It takes a whole team of specialists to diagnose and treat this incredibly rare condition.

It can be temporary or permanent — and treatments are hit or miss with highly variable success rates. Studying foreign accent syndrome hasn't just helped us understand and treat these rare cases — it's produced insights into other conditions as well. Researchers writing in the British Medical Journal in 2013 noted that children with autism spectrum disorders have been documented with accent changes that resemble foreign accent syndrome.

And researchers are trying to work out if that's a coincidence, or if it tells us something about how the brain works in both cases. Could foreign accent syndrome develop as a consequence of autism? Or is it a totally unrelated occurrence?

If they are related, it could mean that what we know about foreign accent syndrome could help us map out the brain changes that occur with autism, possibly leading to new diagnostic methods and therapies. There have only been around one hundred cases of foreign accent syndrome documented since the first case was described in 1907. This is a rare phenomenon, and you're probably not going to wake up tomorrow with a new accent.

But this bizarre condition illustrates that the consequences of brain disorders and damage can manifest in really unexpected ways. And our brains are so complex and interconnected that studying one, super-rare disorder can lead to a better understanding of another that affects way more people. We know you guys like to stay on top of all the latest and greatest developments in science and technology.

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