Susceptibility to Residual Inhibition is Associated with Hearing Loss and Tinnitus Chronicity
Suyi Hu, Lukas Anschuetz, View ORCID ProfileDeborah A. Hall, Marco Caversaccio, Wilhelm Wimmer
This article is a preprint and has not been certified by peer review [what does this mean?]. It reports new medical research that has yet to be evaluated and so should not be used to guide clinical practice.
Residual inhibition, i.e. the temporary suppression of tinnitus loudness after acoustic stimulation, is a frequently observed phenomenon that may have prognostic value for clinical applications. However, it is unclear in which subjects residual inhibition is more likely and how stable the suppression can be induced repeatedly. The primary aim of this work was to evaluate the effect of hearing loss and tinnitus chronicity on residual inhibition susceptibility. The secondary aim was to investigate the short-term repeatability of residual inhibition. Residual inhibition was assessed in 74 tinnitus subjects with 60-second narrow-band noise stimuli in 10 consecutive trials. The subjects were assigned to groups according to their depth of suppression (substantial residual inhibition vs. comparator group). In addition, a categorization in normal hearing and hearing loss groups, related to the degree of hearing loss at the frequency corresponding to the tinnitus pitch, was made. Logistic regression was used to identify factors associated with susceptibility to residual inhibition. Repeatability of residual inhibition was assessed using mixed-effects ordinal regression including post-stimulus time and repetitions as factors. Tinnitus chronicity was not associated with residual inhibition for subjects with hearing loss, while a statistically significant negative association between tinnitus chronicity and residual inhibition susceptibility was observed in normal hearing subjects (odds ratio: 0.63; CI: 0.41 to 0.83; p = 0.0076). Moreover, repeated states of suppression can be stably induced. Our results suggest that long chronicity and residual inhibition susceptibility could be indicators for hidden lesions along the auditory pathway in subjects with normal hearing thresholds at their tinnitus frequency.