Masking by internally generated noise and protection by middle ear muscle activity

Gross auditory nerve action potentials to high-frequency clicks were recorded bilaterally from awake cats with unilaterally tenotomized middle ear muscles (MEM) during eating and during control quiet periods. Masking by internally generated noise associated with eating increased with decreases in click intensity, but did not differ in ears with intact and tenotomized MEM. Under the conditions of this study, non-reflex MEM activity does not appear to provide protection against masking by internally generated noise.