[Study of tinnitus masking by self-recording audiometer]

The tinnitus masking test, in which the minimum masking levels of tinnitus by various pure tones and band noises are measured and used to produce tinnitus masking curves, is one of the methods for evaluating the character of tinnitus. At present, the tinnitus masking test is usually performed using a pure tone audiometer. In this study, tinnitus masking curves were produced using a self-recording audiometer (Bekesy audiometer) in 22 cases of tinnitus, and the basic nature of the tinnitus masking curves from the self-recording audiometer was investigated and compared with those from a pure tone audiometer. The results showed no changes in the masking level, and the amplitudes of the tinnitus masking curves from the self-recording audiometer were observed to be at the tinnitus pitches. The amplitude of the tinnitus masking curve showed a negative correlation with tinnitus loudness as measured by the loudness balance test for tinnitus, that is, the amplitude tended to decrease as the tinnitus became louder. This suggests that the loudness of the masking tone influences the tinnitus masking phenomenon.