Muse headbands and other sleep tracking devices that monitor your sleep state may be training new AI models of the brain. While not at the level of being able to interpret (or even really monitor) brainwave activity, Interaxon, the company behind Muse, has trained its model on about 50,000 hours of electroencephalography (EEG) data from users of the technology, with a goal of better understanding how the brain works while asleep.