Measurement of the combination tone 2f1-f2 using two-tone forward masking and compound action potential responses.

The presence of the 2f1-f2 combination distortion tone generated when two tones are presented to the cochlea, can be detected using a two-tone complex to forward mask a probe tone. The combination tone is the effective masking agent and the amplitude of the compound action potential response to the probe tone reflects the degree of masking. Excitation patterns, frequency relationships and intensity functions that are obtained with this procedure are consistent with previously published data.