Figure 9.

Effect of noise exposure on ABR pure tone thresholds in not implanted ears over time. Hearing thresholds of the right (not implanted) ears. Where the hearing threshold could not be identified up to the maximum sound stimulus level of 100 dB SPL (85 dB SPL for 40 kHz), the threshold was defined as 110 dB SPL or 95 dB SPL for 40 kHz. Directly after the noise insult, all thresholds increased significantly, except for 500 Hz and 1 kHz (blue line vs. green line, not illustrated). In addition, 7 days after the noise insult, there is significant frequency-specific recovery, except for 40 kHz (significances illustrated between the green and the red line). The remaining significant threshold shift from day 0 pre noise to day 7 was also frequency specific, except for 500 Hz, which showed a full recovery and 1 kHz (significances illustrated between the red and the blue graph). ns = not significant; * p ≤ 0.05; ** p ≤ 0.01; *** p ≤ 0.001.