FIG. 1.

Mean change in test tone ear-canal level induced by the CWN. Each curve is for a different subject or the mean. The change is expressed as the ear-canal level measured without the CWN minus the level measured with the CWN. Negative values indicate that the CWN increased the middle-ear impedance, presumably by activation of the MEM reflex. Shaded areas highlight the approximate range of masker frequencies used in the PTC measurements. A For test tones of 40 dB SPL. B For test tones of 80 dB SPL.