TEMPORARY THRESHOLD SHIFT IN AUDITION INDUCED BY EXPOSURE TO ULTRASOUND VIA BONE CONDUCTION
Vibrations with frequency above 20 kHz presented to the bones of skull are perceived as audible sound. This phenomenon is known as bone-conducted ultrasonic (BCU) perception, but its mechanism has been yet unclear. In the present study, we aimed at clarifying the difference between the processing mechanisms of BCU and ordinary bone-conducted sounds with frequency below 20 kHz (bone-conducted audible sounds: BCA) by measuring the auditory threshold of BCU and BCA sound before and after an exposure to tones or band noises with 1-min duration. In the results, the temporary threshold shift for BCU sounds showed similar characteristics to that for BCA sound, particularly when the same stimuli were presented as exposure. These results indicate that BCU and BCA shared some common auditory processing mechanisms.