Sara Henya’s art is her music and she makes playing the harp look effortless.

But when her fingers are still, that’s a different story. Her brain barks orders her body cannot ignore. She may hit herself in the face. Maybe she will need to hit her elbows hard against the back of a chair. And then there are the sounds. They erupt out of her.

Profanities. Loud, unwilled. Yet they are as much a part of her as the golden tones she coaxes from her harp. Henya of Northeast Philadelphia is part of a small, largely understudied sisterhood. She is a woman with Tourette’s syndrome.

“It’s kind of precious to me,” said Henya, 24. “If I had to pick whether I would keep it or get rid of it, I would keep it because I feel like my perspective on the world and who I am and how I treat other people is different than it would have been if I didn’t have it.”

Defined as a neurodevelopmental disorder characterized by involuntary, often repetitive movements and vocalizations, Tourette’s is estimated to affect 1 in every 162 children in the U.S., according to research.

But the Centers for Disease Control and Prevention has reported that as few as half of Tourette’s cases are diagnosed.

As with autism and ADHD, males are far more likely to have Tourette’s than females — about four times more likely.

But Anthony Rostain, a Penn Medicine and Children’s Hospital of Philadelphia psychiatrist and member of the Tourette Association of America’s medical advisory board, said he believes that the social burden of Tourette’s is particularly heavy for women.

Some people such as Henya have the more extreme, stereotypical form of Tourette’s. Coprolalia, vocal tics that manifest in cursing, occurs in only about 10% of cases. Tourette’s has no cure, and there is no medication that works for everyone.

Some people can learn to somewhat control their tics at least briefly, but that can be uncomfortable. Highly focused activities, such as playing an instrument or sports, may help suppress tics. Athletes with Tourette’s include soccer star David Beckham. And 17-year-old singer/songwriter Billie Eilish opened up about her Tourette’s after videos of her tics began circulating online. “These compilations y’all been making of my tics are low-key funny even when y’all make fun of them. … just to let ya know it’s tourette’s,” she wrote on Instagram.

Diagnosis rates may be especially low in girls and women, partly because clinicians aren’t used to looking for it. Nearly 90% of people with Tourette’s have at least one other mental, development or behavioral disorder, the CDC said, so those also may be missed.

“If you’re not looking for tics and you miss them, you’re also not looking for OCD to occur,” said Carol Mathews of the University of Florida. “You’re not looking for anxiety. You’re not looking for mood disorders. And those are things that often don’t come to our attention because kids keep them inside.”