Somnee is an American company built from research at the University of California, Berkeley. Its Smart Sleep Headband combines brain sensing with electrical stimulation. Newer versions monitor sleep overnight.

How it works
Electrodes on the forehead detect electrical patterns from brain activity and create a short brain profile. The same contacts then deliver a weak alternating current tuned to that profile, to support the brain rhythms involved in falling asleep. Overnight sensors can track sleep and adjust later sessions. An app provides reports and controls.

Key considerations
Good skin contact is essential, and adhesive hydrogel electrodes need regular replacement. The headband requires charging and may feel uncomfortable during sleep. Evidence for the exact commercial system is still developing, and individual responses vary. Sleep stages are estimates.