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.
http://www.technologyreview.com/news/518356/device-could-spo...
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.