8 teen girls are proof TikTok is not to blame for the rise in social tics, CDC says

• Reports of teenage girls around the world developing Tourette's-like tics have been mounting in recent months.
• Studies have suggested social media, and TikTok in particular, may be to blame for spreading the tics.

From the US to Germany, Canada, the UK and Australia, doctors around the world have been diagnosing an unusually high number of teens with tics during the pandemic.

The patients, more often female than male, may quickly wrinkle up their nose, sniff, blink, clear their throat, jerk their head, or shrug their shoulders. These involuntary tics can be debilitating, frequent enough to make it impossible to drive a car, or attend work or school.

In one highly unusual instance of a tic contagion last fall, eight teenage girls (aged 15 to 17 years old) in Minnesota all developed functional tics together between late September and October 2021. The girls were friends, or had contact through extracurricular activities. In one way or another, they spent time around each other, and were excited to do so after many months of pandemic isolation. But when they saw each other, their tics only worsened.

Suddenly, their abs would tense up, their heads would jerk, shoulders shrug, eyes blink rapidly. Repetitive movements and sounds spread through the group almost like a yawn would.

A June 2021 scientific paper, which described how functional tics spread through six other teenage girls, produced one of the very first clear explanations for the recent global rise in teen tics: TikTok. But, as disease investigators in Minnesota would soon find out, the real explanation for the sharp pandemic uptick in teen tics is far more complicated than that. In fact, the pandemic itself is likely partially to blame.

A simple but flawed explanation, blaming TikTok for the tics, quickly took on a life of its own

"Physicians at hospitals all over the world are reporting a rapid rise in teen girls developing tics believed to be derived from TikTok," Dr. Oz, the TV physician who's now a Trump-backed US Senate candidate, said during a medical mystery segment of his show in December 2021.

A teenage guest on Oz's show, Chailyn, developed tics during the pandemic. She said it just happened to her one day, while she was watching a movie. The tics would grow worse when she attended work or school, and she had to stop going for a while, though she said her condition is improving now, and she's resuming some activities.

"I personally don't think my tics were triggered by anything on TikTok," she said.

Regardless, a chyron quickly flashed across the bottom of the TV screen: "TikTok causing tics in users? Doctors say it's no joke."

It wasn't just Dr. Oz blaming TikTok.

Many scientific studies and articles in recent months have suggested that this outbreak in teen tics can be explained by social media — the rise in functional tics, they say, are largely a result of people watching others tic on TikTok.

In Alberta, Canada, Dr. Tamara Pringsheim, a neurologist who normally sees just one or two new functional tic patients per year was suddenly overcome with dozens of new cases in just a few months.

"In the course of one week I saw 10 different people who were all clapping, whistling, clicking, popping, saying the same words like 'knock knock,' 'woo hoo,' 'beans,'" she said on the Neurology podcast. It seemed to fit with the alluring idea that TikTok was to blame.

But it's not that TikTok causes tics. Watching others tic — whether on TikTok or in real life — can prompt more tics. It's a lot like how watching someone yawn can make you yawn. Whether that's in real life, or through videos posted online, being around others who tic can make a person's condition worse. The same is true of Tourette's. Generally, excitement and anxiety can exacerbate these conditions too.

Before TikTok, there were other ways people would explain away tic contagions. They were dismissed as a kind of "mass hysteria" for many decades. When hysteria became passé, it was called "conversion disorder." That's what people said happened when 18 high school girls in the small town of Le Roy, New York all developed tics around the same time in the fall of 2011. Now, clinicians prefer the term, "functional neurological disorder," or FND.

"It's very easy just to blame one thing for this, blame social media," Jon Stone, a neurology professor at the University of Edinburgh, said.

Stone, a leading expert on FND, has authored a helpful webpage about the condition, the possible mechanisms behind it, and how it can be treated. He believes what we are seeing in Minnesota is another exceptionally rare cluster of FND cases, just like what happened in LeRoy in 2011.

"The assumption that everyone's been making — that it's all social media and TikTok — is really much too simplistic and has caused a lot of damage, actually," he said. "It's encouraging people not to take this problem seriously and say, 'oh, you've just been watching too much TikTok.'"

To truly understand this issue, Stone said, we need to appreciate the complex ways anxiety, loneliness, and depression can affect our brains, at times manifesting in physical actions.

The unique combination of factors that can cause functional neurological disorders

Researchers have found a web of biological, psychological, and social factors at work with functional neurologic disorders like tics. They can't be neatly explained away by social media use. Trauma, anxiety, and depression can all play a role, but don't always.

"People really are paralyzed — they're not imagining it, they're not pretending," Stone explained.

Somewhere between 1 in 8,000 people and 1 in 25,000 people have some kind of FND, which can include paralysis, seizures, or tics.

But most tics aren't picked up from friends or schoolmates, nor is there good evidence that they're overwhelmingly primed by social media. Instead, a more complex mix of stress, anxiety and depression in many cases, and genetic predispositions may drive the condition. A March 2022 study of 185 Australian tic patients found just 18% had previous exposure to tics on social media when they developed symptoms.

Stone said "it's clear that for some patients social media has been an important trigger," due in large part to the fact that people who may be prone to developing tics can now easily watch videos of others with tics around the globe.

"I have to say, the patients that I've seen with functional tics, I don't think any of them — at least they didn't admit to me that it was relevant," Stone said of social media. "Quite a few of them started looking at videos of tics after their tics developed. Because they wanted to know more about them. And that's what a teenager does, is look at TikToks."

The Minnesotan teens — who used Snapchat more than TikTok — were stressed, anxious, and lonely

There are other factors that seem to play a more important role than social media in a majority of the new tic cases.

Melanie Firestone, the Centers for Disease Control and Prevention "disease detective" who investigated the Minnesota cluster, said "we didn't have any evidence in this particular investigation that social media was directly related to the symptoms that these students were experiencing." (Besides, the girls were on Snapchat more than TikTok.)

What linked the girls together more so than anything they did on their smartphones was how they felt. Stressed, anxious, depressed, lonely.

At least five of the eight girls screened positive for depression, and seven of the eight teens screened positive for anxiety.

Across the globe in Australia, 95% of the pediatric tic patients in the March 2022 study also had a history of anxiety or depression.

They are far from alone. Experts say rates of depression and anxiety in teenage girls, which were already on the rise before the pandemic began, have only gotten worse.

"The experience of these students really just highlights how stress and mental health can affect us in such unique ways," Firestone said. "The feelings that people are feeling — it's an important experience."

Most pandemic tic patients have recovered, or are doing better. Cognitive behavioral therapy may help.

Stone says that the recent rise in tic cases is "perhaps more because teenagers have had a horrendously abnormal time" during the pandemic, "stuck in their bedrooms, away from their friends," and that has all had an impact on their brain development.

Pringsheim, the Canadian doctor, says many of her pandemic patients have improved. Many are using cognitive behavioral therapy alongside antidepressant drugs to treat underlying depression and help patients talk about how they're feeling.

In Minnesota, as of January, all but one of the girls who developed a tic at the beginning of the schoolyear had recovered.