Mobile EEG cap to enable brainwave monitoring on the go
Like many scientists around the world, researchers working out of UC San Diego have high hopes for how our brainwaves might one day be used to control devices, tackle neurological disorders and everything in between. But for that to happen, the devices used to monitor them not only have to be highly advanced, but comfortable and practical to wear on our heads in everyday environments. The team has now taken a promising step towards such a future, unveiling what it says to be a first-of-its-kind EEG headset that will take brain monitoring out of the lab and into homes, cars and offices.
Mobile, consumer friendly electroencephalography (EEG) devices have taken various forms since the first commercial version appeared in 2008. From brain-training headbands to stress-relieving musical headsets attuned to our brainwaves, we are already getting an exciting glimpse of where the technology might be headed.
But some of the truly exciting stuff is happening inside the lab, where researchers are able to rig up more sophisticated systems that convert brain signals into input commands for devices. These have included controlling Parrot AR Drones and larger fixed-wing unmanned aircraft, as well enabling people with paralysis or other physical impairments to control wheelchairs and robotic arms.
The UC San Diego team is now claiming to have developed a portable EEG device with comparable capabilities to those found in research labs – an achievement that could help bring these types of brain-machine-interface capabilities out into the real world. The 64-channel headset's shape is likened to an octopus by the researchers, in that its set of arms wrapping around the head are elastic to accommodate different sized noggins.
The materials used are the product of four years of work, with the system relying on dry electrodes rather than wet ones, which require less skin preparation. The sensors designed to work on the hair (seen above) are a mix of silver and carbon on a flexible substrate, which enables flexibility and durability while maintaining high quality signals. The sensors working on bare skin are made from a hydrogel which is housed inside a conductive membrane. These also feature an amplifier to boost signal quality and block out interference from other electrical equipment.
The team has also developed special software to analyze the incoming signals captured by the headset. This involved designing an algorithm to isolate the brainwaves from other signals generated when a subject moves, speaks or blinks.
"This is going to take neuroimaging to the next level by deploying on a much larger scale," said Mike Yu Chi, a UC San Diego alumnus who led the team that developed the headset. "You will be able to work in subjects' homes. You can put this on someone driving."
Chi is the CEO of the startup Cognionics, which sells the newly developed headset to research groups. The ultimate aim for he and the rest of the team is to have the headset used in clinics to diagnose various neurological conditions like strokes and seizures.
"We will be able to prompt the brain to fix its own problems," says Gert Cauwenberghs, a bioengineering professor at UC San Diego. "We are trying to get away from invasive technologies, such as deep brain stimulation and prescription medications, and instead start up a repair process by using the brain's synaptic plasticity."
The research was published in the journal IEEE Transactions on Biomedical Engineering.
Source: UC San Diego