DOI: 10.5061/dryad.sh565
title: Data from: Cortical reorganisation during a 30-week tinnitus treatment program

description: Subjective tinnitus is characterised by the conscious perception of a
 phantom sound. Previous studies have shown that individuals with chronic
 tinnitus have disrupted sound-evoked cortical tonotopic maps, time-shifted
 evoked auditory responses, and altered oscillatory cortical activity. The
 main objectives of this study were to: (i) compare sound-evoked brain
 responses and cortical tonotopic maps in individuals with bilateral
 tinnitus and those without tinnitus; and (ii) investigate whether changes
 in these sound-evoked responses occur with amelioration of the tinnitus
 percept during a 30-week tinnitus treatment program.
 Magnetoencephalography (MEG) recordings of 12 bilateral tinnitus
 participants and 10 control normal-hearing subjects reporting no tinnitus
 were recorded at baseline, using 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz
 tones presented monaurally at 70 dBSPL through insert tube phones. For the
 tinnitus participants, MEG recordings were obtained at 5-, 10-, 20- and
 30- week time points during tinnitus treatment. Results for the 500 Hz and
 1000 Hz sources (where hearing thresholds were within normal limits for
 all participants) showed that the tinnitus participants had a
 significantly larger and more anteriorly located source strengths when
 compared to the non-tinnitus participants. During the 30-week tinnitus
 treatment, the participants’ 500 Hz and 1000 Hz source strengths remained
 higher than the non-tinnitus participants; however, the source locations
 shifted towards the direction recorded from the non-tinnitus control
 group. Further, in the left hemisphere, there was a time-shifted
 association between the trajectory of change of the individual’s objective
 (source strength and anterior-posterior source location) and subjective
 measures (using tinnitus reaction questionnaire, TRQ). The differences in
 source strength between the two groups suggest that individuals with
 tinnitus have enhanced central gain which is not significantly influenced
 by the tinnitus treatment, and may result from the hearing loss per se. On
 the other hand, the shifts in the tonotopic map towards the non-tinnitus
 participants’ source location suggests that the tinnitus treatment might
 reduce the disruptions in the map, presumably produced by the tinnitus
 percept directly or indirectly. Further, the similarity in the trajectory
 of change across the objective and subjective parameters after
 time-shifting the perceptual changes by 5 weeks suggests that during or
 following treatment, perceptual changes in the tinnitus percept may
 precede neurophysiological changes. Subgroup analyses conducted by
 magnitude of hearing loss suggest that there were no differences in the
 500 Hz and 1000 Hz source strength amplitudes for the mild-moderate
 compared with the mild-severe hearing loss subgroup, although the mean
 source strength was consistently higher for the mild-severe subgroup.
 Further, the mild-severe subgroup had 500 Hz and 1000 Hz source locations
 located more anteriorly (i.e., more disrupted compared to the control
 group) compared to the mild-moderate group, although this was trending
 towards significance only for the 500Hz left hemisphere source. While the
 small numbers of participants within the subgroup analyses reduce the
 statistical power, this study suggests that those with greater magnitudes
 of hearing loss show greater cortical disruptions with tinnitus and that
 tinnitus treatment appears to reduce the tonotopic map disruptions but not
 the source strength (or central gain).
description: READ
 MEBehavioural tinnitus
 distress data (TRQ)This spreadsheet contain
 the 5 recording session data from 12 tinnitus subjects.TRQ_data.xlsxT1 - tinnitus subject 1Magnetoencephalography files for tinnitus subject 1.T1.7zT2 - tinnitus subject 2Magnetoencephalography files for tinnitus subject 2.T2.7zT3 - tinnitus subject 3Magnetoencephalography files for tinnitus subject 3.T3.7zT4 - tinnitus subject 4Magnetoencephalography files for tinnitus subject 4.T4.7zT5 - tinnitus subject 5Magnetoencephalography files for tinnitus subject 5.T5.7zT6 - tinnitus subject 6Magnetoencephalography files for tinnitus subject 6.T6.7zT7 - tinnitus subject 7Magnetoencephalography files for tinnitus subject 7.T7.7zT8 - tinnitus subject 8Magnetoencephalography files for tinnitus subject 8.T8.7zT9 - tinnitus subject 9Magnetoencephalography files for tinnitus subject 9.T9.7zT10 - tinnitus subject 10Magnetoencephalography files for tinnitus subject 10.T10.7zT11 - tinnitus subject 11Magnetoencephalography files for tinnitus subject 11.T11.7zT12 - tinnitus subject 12Magnetoencephalography files for tinnitus subject 12.T12.7zControl subjects (10 total)Magnetoencephalography files from 10 normal (non-tinnitus) subjects. 1 MEG session per subject.Control.7z