Mayo Clinic is developing a smartwatch app that can head off or shorten temper tantrums by monitoring children for clinically meaningful changes in heart rate and restlessness.

Researchers recently found the smartwatches could cut the length of tantrums in half by using biometric data to identify agitated children and alert parents to step in. Now Mayo has received a $300,000 federal grant to see if the smartwatches can let children know directly about their agitation and help them defuse tantrums on their own.

Tantrums might be everyday occurrences, but they can be destructive for the 4.5 million U.S. children with behavior disorders who struggle to control them once they start, said Dr. Magdalena Romanowicz, a Mayo child psychiatrist who co-led the study.

“It’s true that it could be just kind of a rite of passage — brief flashes of anger that some kids have,” she said. “But we’re talking about significant, severe, disruptive behaviors that lead to day care expulsions and that sort of thing, often in the context of other mental health issues.”

Rochester, Minnesota, parents Jared and Sarah Staal could relate, and they were eager to volunteer for an initial phase of Mayo’s research two years ago after their then-5-year-old son was diagnosed with attention deficit hyperactivity disorder. His tantrums could last an hour and couldn’t be stopped once they started.

“If you don’t see the signs, it’s like he’s filling up a gas tank that’s getting ready to launch to the moon,” the father said. “If you don’t intervene and figure out the cues before ignition, then you just wait until the rocket fuel tank is empty.”

Mayo’s first-of-its-kind smartwatch research had a fluky origin. Romanowicz was providing parent-child interaction therapy to young families, whose children sometimes would run angrily out of sessions and past the office of Arjun Athreya, an electrical and computer engineer studying AI-powered solutions for health care.

Athreya took an interest in the therapy and wondered if he could develop an early warning system that reminded parents at key moments what to do.

“All of the therapies we provide are effective only if parents can remember when and what to do so they can regulate their child effectively,” he said.

Step one involved monitoring the moods and biometrics of children admitted for inpatient psychiatric care. AI-assisted analysis of smartwatch data made a discovery: if the children’s heart rates accelerated to a certain level for 10 minutes, but they weren’t playing or moving, then the children were likely internalizing frustrations and nearing outward tantrums.

The researchers broadly defined tantrums as unusually intense outbursts or defiant behaviors, noting that most resolve within 15 minutes, but those lasting 25 minutes or longer are indicative of mental illness.

The Mayo team’s first paper showed three years ago that the smartwatches were 81% accurate at assessing the moods of hospitalized children and gave as much as 60-minute warnings of tantrums. They also digitally documented the length of tantrums, which Athreya said hadn’t been done before.

The next discovery emerged late last year, after Mayo researchers recruited 50 children ages 3 to 7 with behavior disorders and parents, including the Staals. Results were compared between 22 children who received weekly interactive family therapy and 28 who also wore smartwatches.

Researchers were pleased that the children wore their smartwatches more than 70% of the time, even at school or when sleeping. That alone proved that commercially available smartwatches could be clinically useful.

They also discovered that parents were alerted in 4 seconds when the smartwatches picked up biometric signals in children suggesting tantrum risks. Parents were reminded via their mobile devices of strategies for responding to their children in these moments, and to stay calm.

“You cannot calm down another human being if you are not calm yourself,” Romanowicz said.

Tantrums among children wearing the smartwatches lasted 10 minutes on average during the study, compared to 22 minutes among the children participating in therapy alone. The results were published in JAMA Network Open, an online medical journal, and featured last week at Mayo’s conference on artificial intelligence (AI).

The smartwatch is one of numerous AI-enabled improvements envisioned by Mayo Clinic, which last week announced a deal with Microsoft Corp. to develop a frontier AI model that can ignore irrelevant clutter and focus on data and information that improves medical care.

The smartwatch system was an important teaching tool alongside the therapy sessions for the Staals, who are both Mayo executives eager to assist with the health system’s research. Their son enjoyed wearing the watch all the time just because it was counting his steps.

Now the parents know the signs of emerging tantrums without technical assistance, and how to respond. They also have adjusted their at-home routines to reduce tantrum risks, recognizing that the medications that help their son at school have worn off by afternoon.

“We still implement a lot of those learnings to this day,” the mother said.

Romanowicz said the researchers were thoughtful about the brevity and content of advice they sent to parents via mobile devices when tantrum risks emerged in their children.

She said they are being similarly deliberate in shaping messages for the next study that will alert children to their own tantrum risks. The messages might encourage “turkey breathing,” a mindfulness exercise by which children take deep breaths while tracing over their fingers or a drawing of a turkey.

Mayo also is developing a publicly accessible app by which parents can submit information about tantrums and improve the precision of the predictive model powering its smartwatches.

While the smartwatches were designed to complement ongoing family therapy, Romanowicz said their usage could expand.

The waitlist is six months for parents wanting to bring their preschool children to Mayo for interactive therapy. Smartwatches could provide initial advice and support for them while they wait.

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