Hearing thresholds during Gz acceleration with masking noise.

Background: Future fighter aircraft will include three-dimensional sound signals as part of the human-machine interface. The reduction in cerebral vascular flow associated with maneuvering acceleration (+Gz) may affect a pilot's ability to perceive and interpret such aural cues. We hypothesized that vascular deprivation along the cochlea produced by +Gz would raise hearing thresholds either globally or specifically at 1000 Hz.