Billie Eilish talked about Tourette Syndrome in an interview with David Letterman for his Netflix series, "My Next Guest Needs No Introduction."

Billie was diagnosed at age 11 with neurological disorder, which can cause uncontrollable and unwanted sounds and / or repetitive movements. She said people sometimes misunderstand what is happening.

"The most common way people react is by laughing because they think I'm trying to be funny," she said. "And I'm always extremely offended by that."

Billie added that some of the nervous tics have calmed down, but not all. "These are things you will never notice if you are just having a conversation with me. But to me they are very exhausting."

She said she is happy to talk about it and added that she does not experience tics during the time she is performing.

Tourette syndrome is a problem with the nervous system that causes people to move or make sudden sounds, called tics, that they cannot control. For example, someone with Tourette can rub their eyes or clear their throat over and over again. Some people may say words they do not intend to say.

Tickets are divided into motor and vocal tics. Motor tics include cracking of the arm or head, blinking of the eyes, making a certain habit, raising the shoulders, and so on. Vocal cues include clearing the throat, coughing, cheering, sniffing, repeating what someone else is saying, and so on.

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