I saw a professor demolish one of these devices by simply instructing his students using it to "think" without moving their eyes or eyebrows. At that point the

I saw a professor demolish one of these devices by simply instructing his students using it to "think" without moving their eyes or eyebrows. At that point the device stopped working, because not surprisingly the action potential in our faces muscle movements far exceed anything the brain produces in terms of EEG signals when measured from our skin. Trying to read brain signals from a skin-based EEG device is like trying to listen in on a conversation being had inside a packed sports stadium while you fly over it in a helicopter.