The dissociation of SOAEs and tinnitus

Spontaneous oto-acoustic emissions (SOAEs) were detected in 10 of 29 subjects with tinnitus. Because measures of the pitch of tinnitus are highly variable, the relation between the frequency composition of the tinnitus and the frequencies of SOAEs can not be known precisely. This raises the question of whether an observed SOAE could be proven to be the physical basis of an audible tinnitus of unspecified composition. To examine this question, subjects with both SOAEs and tinnitus participated in two demonstrations. First, while the tinnitus was reportedly masked by a high-frequency tone, the SOAE was unchanged. Second, while the SOAE was suppressed, the tinnitus was reportedly audible. Although masking and suppression are not equivalent operations, these findings make it likely that the SOAE and the tinnitus are independent phenomena, at least for these subjects. Additional evidence of the dissociation of SOAEs and tinnitus in these subjects is provided by data showing that suppression tuning curves for SOAEs are frequency-specific, whereas tones at any frequency are equally effective in masking the tinnitus.