Billie Eilish has spoken out about living with Tourette’s syndrome and cleared up some common misconceptions about the condition.

Speaking on the Netflix show My Next Guest Needs No Introduction with David Letterman, the 20-year-old artist said she was first diagnosed with Tourette’s when she was 11 years old.

Tourette’s is an often misunderstood condition, stereotyped as making people swear or say socially inappropriate things. While some people with the condition might experience involuntary vocalizations, Tourette’s is better characterized by repetitive movements or unwanted sounds, known as tics, that can’t be easily controlled.

According to Tourette’s Action, just 10 percent of people with the condition also experience uncontrolled swearing. Equally, not all people with tics have Tourette’s, as this particular condition is just part of a wider spectrum of tic disorders.

As Billie explains, tics can often be very subtle and may consist of little more than a twitch, a blink, or a flick of the head.

“These are things you would never notice if you’re just having a conversation with me, but for me, they’re very exhausting,” Billie said.

“If you film me for long enough, you’re going to see lots of tics,” she added

“The most common way that people react is they laugh because they think I’m trying to be funny. I’m always left incredibly offended by that.”

Billie spoke candidly about the condition after experiencing a tic while being interviewed by Letterman. She went on to say how she “really loves” discussing Tourette’s syndrome and that she’s “very happy talking about it.”

“It’s very, very interesting, and I am incredibly confused by it,” she added. “I don’t get it.”

It’s not fully known how many people live with Tourette’s syndrome, although one study found it affects between 0.3 percent to 1 percent of the general population in Europe. Another study estimated that approximately 1 out of every 162 children (0.6 percent) have the condition.

Around 5 out of 6 children with Tourette’s syndrome are also diagnosed with at least one additional mental, behavioral, or developmental condition. In one study of children diagnosed with Tourette’s, approximately 61 percent had anxiety, 52 percent had ADHD, 34 percent had behavioral problems, 34 percent had learning disabilities, 21 percent had autism spectrum disorder, and 20 percent had depression.

The cause of Tourette’s syndrome is not known for sure. It’s thought to be linked to part of the brain that helps regulate body movements called the basal ganglia, and the imbalance of neurotransmitters such as dopamine. It’s also evident that both environmental and genetic factors play a role in the development of the condition.

There’s no “cure” for Tourette’s syndrome, although there are a number of ways some people help to manage their condition. This includes behavioral therapies that provide tools for helping a person learn ways to change certain behaviors, and medication.