Humes LE. The effects of middle ear muscle contraction on auditory and overload thresholds.
AUDIOLOGY : OFFICIAL ORGAN OF THE INTERNATIONAL SOCIETY OF AUDIOLOGY 1978;
17:360-7. [PMID:
687241 DOI:
10.3109/00206097809101305]
[Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The present investigation examined psychophysically the frequency-specific and nonlinear attenuation of sound energy provided by middle ear muscle contraction in normal hearers. Aural overload and absolute auditory thresholds were measured at 500, 1 000 and 2 000 Hz prior to and during acoustic stapedial reflex contraction. Reflex contraction was elicited with contralateral broad-band noise. Results revealed that overload thresholds were elevated at 500 and 1 000 Hz and a slight decrease in overload threshold was apparent at 2 000 Hz during reflex contraction while absolute thresholds remained essentially unchanged. These data are consistent with previous psychophysical and physiological findings. The aural overload test having been derived directly from observations of cochlear microphonic saturation, moreover, affords direct comparison to results of electrophysiological experimentation.
Collapse