Normal brief-tone bone-conduction behavioral thresholds using the B-71 transducer: three occlusion conditions.

Behavioral thresholds were measured from 31 adults with normal hearing for 500, 1000, 2000, and 4000 Hz brief tones presented using a B-71 bone oscillator. Three occlusion conditions were assessed: ears unoccluded, one ear occluded, and both ears occluded. Mean threshold force levels were 67, 54, 49, and 41 dB re:1 microN peak-to-peak equivalent in the unoccluded condition for 500, 1000, 2000, and 4000 Hz, respectively (corrected for air-conduction pure-tone thresholds). A significant occlusion effect was observed for 500 and 1000 Hz stimuli. These thresholds may be used as the 0 dB nHL (normal-hearing level) for brief-tone bone-conduction stimuli for auditory brainstem response testing.