A year ago James Burton tried out some EEG devices for his project [1], and it seemed like noise filtering (funny enough he had to filter the AC frequency commonly used in UK grid) and things such as "skin moisture" affected the electrode outputs quite a bit. Is this still the case when using EEG devices, including this implementation?
Basically, an EEG picking up brainwaves is like standing on one side of a canyon and listening for whispers from your friend on the other side, and occasionally a caravan of trucks drive through. The brains electrical signal is super weak, and you have to pick up what you can from the other side of the skull by comparing voltages in different areas. The thing is, if someone raises their eyebrows, that electrical muscle impulse is enough to blow out whatever signal you were seeing. Skin moisture, the entropic and decaying nature of the universe, all that stuff is fighting against you. It’s a miracle that EEG works as well as it does for the medical purposes where it frequently provides life-saving information.