Temporary threshold shift produced by low‐ and high‐frequency tones

A subject with normal hearing was exposed to pure tones of 125 and 10 000 Hz at 105 dB SPL for 15 min. Temporary threshold shift (TTS) was measured at frequencies of 100–10 000 Hz by automatic audiometry. The maximal TTS was produced in the frequency regions of 500–1000 Hz by an exposure to a 125‐Hz tone and in the frequency areas of approximately 12 oct below the exposure tone, i.e., 5500–6000 Hz, by 10 000‐Hz tone. An exposure to a low‐frequency tone, 125 Hz, did not demonstrate the 12‐oct shift as shown by exposures to other frequency tones. The TTS phenomenon by an exposure to a high‐frequency tone, 10 000 Hz, was not consistent with the idea of a basalward migration of the traveling wave envelope. These findings were compared and discussed with the TTS results of exposure to other frequencies.