Billie Eilish is opening up about what it’s like with living with Tourette’s syndrome.

The Grammy-winning singer talked about navigating the neurological disorder after experiencing a tic on camera during an interview with David Letterman for his Netflix series “My Next Guest Needs No Introduction.”

“If you film me for long enough, you’re gonna see lots of tics,” Eilish told Letterman.

Eilish, who was diagnosed at age 11, said that people who aren’t aware she has Tourette’s often don’t recognize her tics during social interactions and respond insensitively to them.

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

Tourette Syndrome (TS) is a condition of the nervous system. TS causes people to have “tics”. Tics are sudden twitches, movements, or sounds that people do repeatedly. People who have tics cannot stop their body from doing these things. For example, a person might keep blinking over and over.

In becoming a public figure, the 20-year-old said she’s realized the disorder is much more common than she initially thought.

“What’s funny is so many people have it that you would never know,” Eilish said. “A couple artists came forward and said, ‘I’ve actually always had Tourette’s,’ and I’m not gonna out them because they don’t wanna talk about it, but that was actually really interesting to me.”

While Eilish said some of her tics subside over time, there are subtle tics that remain a part of her daily life. “These are things you would never notice if you’re just having a conversation with me, but for me, they’re very exhausting,” she said.

But the “Happier than Ever” singer revealed she doesn’t experience tics while she’s performing onstage. “When I’m moving around, I’m not even ticcing at all,” she explained.

Billie Eilish shared with Letterman that she’s gained confidence in having the disorder, and while she may not have all the answers, she’s “very happy talking about it.”

“I really love answering questions about it because it’s very, very interesting, and I am incredibly confused by it,” Eilish said. “I don’t get it.”