Since the Theta level is associated with sleep, the subject concerned may progress from a fully awake to a sleep state (provided that he does not consciously resist) as the brain strives to entrain its wave frequency output with the one which the person hears.
Shedar (stars.astro.illinois.edu) SHEDAR (Alpha Cassiopiae). The southernmost star of Cassiopeia’s famed Chair, Shedar is also the brightest, though not by much and not all of the time.