ABSTRACT
Background and Objectives@#Tinnitus frequency-filtered music therapy aims to restore lateral inhibition to reverse tonotopic reorganization in the auditory cortex. Although the tinnitus-relieving effect of this therapy has been investigated, the results remain controversial. We performed a prospective, randomized, controlled double-blind study to determine the tinnitus-suppressing effect of tinnitus frequency-filtered music therapy. @*Subjects and Methods@#The study included 90 participants who were randomly categorized into an experimental group that listened to tinnitus frequency-filtered music and a control group that listened to music from which a random frequency was removed. The Tinnitus Handicap Inventory (THI) score and measures of tinnitus loudness, daily awareness, and tinnitus-induced annoyance were evaluated at the initial visit and at 3 and 6 months (final follow-up). The rates of improvement in THI scores in the two groups were also recorded. @*Results@#All measured variables showed significant improvement in both groups, except the matched tinnitus loudness and minimal masking level. However, no significant intergroup differences were observed in the amount of improvement in THI scores and any other variable. The rates of improvement in THI scores were higher in the control group at 3 and 6 months. @*Conclusions@#Listening to tinnitus frequency-filtered music reduced tinnitus-induced handicaps; however, this approach was not significantly better than listening to music from which a random frequency was removed.
ABSTRACT
BACKGROUND AND OBJECTIVES: Changes in distortion product otoacoustic emission (DPOAE) caused by contralateral suppression (CS) allow the function of the auditory efferent system to be evaluated. Parameters affording maximum CS are preferred in terms of clinical application. Our objective was to evaluate the effects of primary levels and frequencies on DPOAE-mediated CS. SUBJECTS AND METHODS: Sixteen subjects with normal hearing participated. DPOAEs were recorded with and without contralateral acoustic stimulation; we delivered broadband noise of 65 dB SPL at f2 frequencies between 1,000 Hz and 6,727 Hz, at 8 pt/octave. The L2 was varied between 40 dB SPL and 80 dB SPL in 10-dB steps. RESULTS: L2 did not significantly affect DPOAE-mediated CS. Higher L2 levels significantly reduced the fine structure depth of both the baseline and suppressed DPOAE datasets. The amount of CS was greatly affected by the f2 frequency; lower and higher frequency ranges afforded significantly stronger suppression than did mid-frequencies within the studied range. CONCLUSIONS: Our findings suggest that DPOAE CS should be measured over a wide range of frequencies as the amount of CS seems to be highly dependent on f2. The use of a higher L2 level may be optimal when it is sought to evoke strong DPOAE-mediated suppression while simultaneously minimizing DPOAE fine structure. Our findings may assist in optimization of clinical procedures evaluating the integrity of the auditory efferent system.
Subject(s)
Acoustic Stimulation , Dataset , Hearing , NoiseABSTRACT
BACKGROUND AND OBJECTIVES: We compared functional MRI acquisition methods of sparse temporal acquisition (STA) and continuous acquisition (CA) to estimate the effect of MRI scanner background noise (SBN) on blood oxygen level-dependent (BOLD) activation of cortical and subcortical auditory centers during auditory stimulation. SUBJECTS AND METHOD: Fourteen healthy subjects (eight males, age 30.6+/-4.7 years) were presented with classical music in a block paradigm (36 s on/off) in two STA [repitition time (TR)=12 s, 60 volumes] and two CA (TR=2 s, 360 volumes) functional MRI sessions. To account for the sample size difference, an additional volume-matched continuous dataset (CAm) was generated by matching CA to 60 volumes of STA. A group-level analysis based on BOLD activation maps was performed. Percent signal change (PSC), T-statistic values and signal variability in cortical and subcortical auditory regions of interest (ROIs) were calculated from individual activation maps and compared between the STA, CA, and CAm. RESULTS: The group analysis showed activation in the primary and secondary auditory cortices in all datasets. However, the activation of subcortical auditory centers above the accepted threshold was only observed in STA. STA (less SBN) showed higher PSCs and T-statistic values in all ROIs except planum temporale when compared to CAm. However, there was no difference in signal variability among the datasets. CONCLUSION: Our results suggest that SBN should be considered as a significant confounder in auditory-evoked functional MRI studies particularly in the activation of subcortical auditory centers, and that STA can be an effective imaging method for reducing the effect of SBN.