Patent ID: 8281787

Claim:
A mask assembly comprising: a body having an internal surface, an external surface, and a perimeter surface; and a forehead support connected to the body; a support bar connected to the forehead support and extending in generally lateral directions from the forehead support to define a pair of sensor sites on said forehead support, with one of the pair of sensor sites being proximate to a FP1 standard electrode placement position of a patient and the other of the pair of sensor sites being proximate to a FP2standard electrode placement position of said patient; a pair of EEG sensors at ends of said support bar, with one of the pair of EEG sensors being held by the support bar at said FP1 standard electrode placement position and the other of the pair of EEG sensors being held by the support bar at said FP2 standard electrode placement position; a control system adapted to receive a signal from said pair of EEG sensors, said control system determining said patient's sleep stage based at least in part on said signal; and a gas delivery device in communication with said control system, wherein said control system is adapted to adjust a gas delivery setting based upon a control system determination of said patient's sleep stage, such that said gas delivery device delivers gas to the patient based on the control system determination of said patient's sleep stage.