HIgh frequency hearing loss from low frequency noise

It has long been believed that the spectrum of hearing loss closely matches that of the presenting noise. An antiquated study by Mill et al showed that this is not always true.

Human subjects were exposed to an octave-band noise for 24 hours. Temporary threshold shifts increased for the first eight hours of exposure and then were asymptotic. While threshold shifts were largest at about one-half octave above the center frequency of the noise, a second maximum was observed at higher test frequencies. The exact frequency of this second maximum decreased from 7.0 kHz, for a noise centered at 2.0 kHz, to 5.5 kHz for a noise centered at 0.5 kHz. This result could be caused by the travelling wave pattern along the cochlear partition or to the production of distortion products.

PubMed