Neuroscientists often use electroencephalography (EEG) as an inexpensive way to record electrical signals in the brain. Though it would be useful to run these recordings for long periods of time, that usually isn’t practical: EEG recording traditionally involves attaching many electrodes and cables to a patient’s scalp.
Now engineers at Imperial College in London have developed an EEG device that can be worn inside the ear, like a hearing aid. They say the device will allow scientists to record EEGs for several days at a time; this would allow doctors to monitor patients who have regularly recurring problems like seizures or microsleep.
“The ideal is to have a very stable recording system, and recordings which are repeatable,” explains co-creator Danilo Mandic. “It’s not interfering with your normal life, because there are acoustic vents so people can hear. After a while, they forget they’re having an EEG.”
By nestling the EEG inside the ear, the engineers avoid a lot of signal noise usually introduced by body movement. They can also ensure that the electrodes are always placed in exactly the same spot, which, they say, will make repeated readings more reliable.
Since the device attaches to just one area, it can record only from the temporal region. This limits its potential applications to events that involve local activity. Tzzy-Ping Jung, co-director of the University of California, San Diego’s Center for Advanced Neurological Engineering, says that this does not mean the device will not be valuable.
“Different modalities will have different applications. I would not rule out the usefulness of any modalities,” says Jung. “I think it’s a very good idea with very promising results.”