Connectivity

A Sleek Wristband That Can Track Seizures

A startup wants to make it easier for people with epilepsy to detect seizures and let others know when they need help.

Nov 28, 2014

A new wristband from a startup called Empatica is built for people with epilepsy—it hopes to detect their seizures and alert family when they’re in the throes of one—but it could also appeal to people who simply want a sleek-looking gadget for logging activities and stress.

The Embrace wristband.

Empatica, which builds wearable devices to measure how biological signals relate to emotions, sought $100,000 in crowdfunding for the device, called Embrace, on IndieGoGo in mid-November. The company met that goal after a day of soliciting donations, and has since raised more than $50,000 on top of it.

Embrace is slated to be available next summer for $199. It will include apps to spot seizures and to let you know when your stress level has risen past a certain point that you’ve set. It also can do things that regular activity trackers do, like track movement and sleep.

The design of Embrace looks more fashion-conscious than health-oriented: a video from Empatica presents it as a wide, thin wristband that wraps around the arm like a slap bracelet. Its square face is dominated by a ring that lights up to communicate time, stress level, and seizure activity. It has a rechargeable battery meant to last more than a week.

MIT Media Lab professor and Empatica chief scientist Rosalind Picard says the idea behind Embrace emerged back in 2008. At the time, she was doing research at MIT that involved using a wristband to track stress levels in autistic kids by measuring their skin conductance—your skin tends to become a better conductor of electricity as your stress level rises. When Picard saw a huge spike in one child’s skin conductance data, she initially figured the wristband’s sensor was broken.

As it turned out, the spike occurred before the child had a tonic-clonic, or grand mal, seizure—the kind that includes both muscle stiffness and jerking movements. Seizures, Picard says, produce high levels of skin conductance.

A year later, Picard went on to cofound a company called Affectiva, which commercialized wearable bands to track stress-related emotions and developed software that could analyze the emotion of people in videos. Affectiva later narrowed its focus to the software, and Picard cofounded Empatica this year to concentrate on wearable sensors.

There are some devices on the market for logging seizures, such as Smart Monitor’s SmartWatch, but they tend to focus on the motion you can track with an accelerometer. Empatica says Embrace is able to measure seizures more accurately  by picking up motion data gathered from the gadget’s accelerometer and gyroscope and combining it with measurements of skin conductance. That is gathered with small electrodes on the inside of its band, which pass a tiny current through your skin and measure how the sweat glands are being stimulated (this can be measured on the skin even if you don’t feel sweaty).

If Empatica’s algorithm detects a seizure, the band will vibrate, giving the user a chance to indicate that there’s been a false alarm. If the user doesn’t respond, it will connect with his or her smartphone to alert a list of people, such as a doctor and family members. The company plans to seek approval for the device from the U.S. Food and Drug Administration, Picard says.

Epilepsy Foundation chairman Warren Lammert—whose group funded an NYU trial to research Embrace and also funded research for SmartWatch—says using a device such as Embrace to track seizures could lead to better insights into how different medications affect epilepsy patients and give more reliable information during clinical trials of new medications.

Daniel Lowenstein, a neurology professor and director of the Epilepsy Center at the University of California, San Francisco, says he’s concerned about Embrace’s seizure-spotting sensitivity and how well it can track different types of seizures. But he notes that it could prove especially valuable for patients who are able to stave off seizures if they know their stress level is climbing. Getting a warning from the band would give them time to pause and do breathing exercises or meditation.