Original Article: PDF OnlyTEMPORARY THRESHOLD SHIFT FROM SHORT-DURATION NOISE BURSTSAHAUS, WILLIAM H.; WARD, W. DIXONAuthor Information Veterans Administration Hospital, Oklahoma City, Oklahoma (W.H.A.) and Hearing Research Laboratory, University of Minnesota, Minneapolis, Minnesota (W.D.W.) Send reprint requests to: William H. Ahaus, Veterans Administration Hospital, Oklahoma City, OK 73104. (Accepted February 21, 1975) Journal of the American Audiology Society: July 1975 - Volume 1 - Issue 1 - p 4-10 Buy Abstract Two experiments were conducted to investigate temporary threshold shift (TTS) from repeated short-duration (<1 sec) noise bursts. Experiment 1 examined whether TTS produced by these intermittent noises followed the so-called on-fraction rule. Subjects received 20 interrupted exposures and one continuous exposure to 1 5 min of band-limited (700-2800 Hz) white noise at 114 dB sound pressure level (SPL). The 20 intermittent noise conditions were combinations of four noise on-fractions (0.125–0.75) and five noise burst durations (12.5–3.750 msec). For on-fractions of 0.25 and greater the on-fraction rule correctly predicted TTS for burst durations of 200 msec and shorter, whereas exposures to noise with burst durations of 800 msec and greater produced less TTS than predicted. For the 0.125 on-fraction more than the predicted TTS was produced by noise bursts shorter than 200 msec, especially so for the 50-msec burst duration. Experiment 2 examined in more detail this particular time region. Ss were exposed to low- and high-frequency octave bands of interrupted noise. each with a burst duration of 50 msec and off-times ranging from 50 to 650 msec. For the low-frequency exposures TTS increased markedly as a function of off-time for noise off-times greater than 150 msec, reaching a maximum at 550 msec; the increase was not as marked for the high-frequency noise. Findings are discussed in terms of their probable relation to the temporal characteristics of the aural reflex. © Williams & Wilkins 1975. All Rights Reserved.