Two experiments, employing different psychophysical procedures, were performed to measure the attenuation at intensities near the threshold due to the acoustic reflex. In both, a contralateral tone was introduced to activate a reflex and the resultant threshold shift for a test tone noted. Shifts observed were small and apparently inconsistent with findings of past experiments. Possible significance of the results was discussed.
The hypothesis was advanced that the reflex, once activated, attenuated loud sounds more than faint ones. Two additional experiments employing a loudness‐matching technique were devised as a test of this hypothesis. In both of these the apparent loudness of different test tones was noted in the presence and absence of a contralateral activating tone. Results were in accord with the prediction. Applications and further tests of the hypothesis are discussed.
