Researchers have developed a 3D-printable electrode that looks like a single strand of human hair and measures brain activity more reliably than the current method used to diagnose things like epilepsy and sleep disorders.When you imagine someone having an electroencephalogram (EEG) to diagnose a condition such as epilepsy, for example, you probably picture them with a head covered in electrodes. That’s because the standard EEG typically uses 21 of them, affixed to the scalp in strategic positio...