The stapedius muscle in relation to sound conduction.

Abstract

The function of the stapedius muscle was investigated by artificially reproducing its action and observing the effects upon the electrical responses of the cochlea. Tension applied through a thread attached to the stapedius tendon causes a marked reduction in transmission for low tones, a smaller reduction for high tones, and for certain tones of the middle range a preliminary improvement and then a considerable decline. The results thus show that in general the stapedius muscle, like the tensor tympani, operates so as to protect the inner ear against overstimulation. A further effect of tension on the stapedius tendon is a significant alteration of the pattern of distortion of the ear.