Hearing a Seizure's Song

Scientists have built a device that converts brain waves into sound waves to detect types of seizures. 

By Gordy Slack|Friday, March 28, 2014
Chris Chafe (left) and a colleague discuss patterns in brain activity.
Linda A. Cicero/Stanford News

The brain of a person seizing sounds to some like atonal and eerie avant-garde music. To others it’s more like a band of coyotes yipping and barking with a crescendo of howls. Of course, the brain itself isn’t making the sounds at all; they’re the product of a new invention that converts brain waves into a vivid audio portrait, providing instant insight into the goings-on inside a person’s head.

The device, called a brain stethoscope, was designed to help recognize and detect types of seizures that — unlike the generalized “grand mal” seizures that leave victims convulsing — present themselves subtly. Some temporal lobe seizures, for example, may cause patients to look absently into the distance and smack their lips. Seizures can disable memory and language, so it can be difficult for patients to describe their episodes afterward. “They may not look like a big deal from the outside, but if you listen in to the brain of a patient having one of these seizures, you can hear that the brain is in seizure,” says Josef Parvizi, a Stanford neuroscientist and epilepsy specialist who developed the brain stethoscope with colleague Chris Chafe, a music researcher at Stanford. If seizure activity goes undetected for too long, it could cause brain damage.


Chafe and Josef Parvizi have developed a device that can turn brain activity into an audio portrait.

Lea Suzuki/The Chronicle/Corbis

Parvizi and Chafe developed the brain stethoscope to allow non-experts to monitor brain activity. Until now, the only reliable way to learn what was going on beneath a seizing patient’s skull was with a hard-to-administer electroencephalogram (EEG), which converts brain activity into visible waveforms that require expertise to interpret. By contrast, Parvizi says, anyone can recognize a seizure with the brain stethoscope. Using the tool, doctors and nurses in the ER or ICU (and eventually home caregivers, Parvizi hopes) can hear immediately if an unresponsive patient is seizing or having some other kind of problem.

The stethoscope picks up brain wave activity through a pair of wearable electrodes that detect electrical emissions from the neurons beneath them. It then converts the signals into sounds, selected by Chafe, that are close in tone to the human voice. Combined signals result in “singing” that indicates the presence and intensity of seizure activity. A prototype is currently being tested in Stanford Hospital’s ICU to see if doctors find it usable and worthwhile.

While seizure activity is dramatic enough to recognize through the stethoscope, normal brain activity sounds more mundane. Still, various normal brain states do sound different, says Chafe, who is also a composer and improvisational musician. Playing his cello, he has already jammed with the stethoscope, riffing off his own brain waves.

Audio produced by Molly Bentley and Gordy Slack. 

[This article originally appeared in print as "Symphony for a Seizure."]

Comment on this article
Collapse bottom bar

Log in to your account

Email address:
Remember me
Forgot your password?
No problem. Click here to have it emailed to you.

Not registered yet?

Register now for FREE. It takes only a few seconds to complete. Register now »