Tone evoked ABR thresholds were measured in a subset of exposed mice at baseline, and at 1, 4, and 8 weeks post-exposure.

<p>(A) Tone exposure in Tinnitus(+) mice induced significant hearing loss at 28 kHz at all post-exposure timepoints, and at 16 kHz 1 week post-exposure. No hearing impairments developed for frequencies between 8 kHz and 22 kHz at 4 and 8 weeks post-exposure. (B) Tone exposure also induced hearing impairments in Tinnitus(-) mice for 28 kHz tone 1 and 4 weeks post-exposure, but not at 8 weeks post-exposure. (C-D) Frequency discrimination thresholds are shown for the subset of mice used for ABR recordings. Thresholds were defined as the frequency shift that caused 50% inhibition of the maximum ASR. (C) Tone exposure in Tinnitus(+) mice led to a decrease in frequency discrimination for the 12 kHz tone at 8 weeks post-exposure, and at 4 weeks post-exposure for the 22 kHz tone. (D) Frequency discrimination thresholds did not significantly change after tone exposure in Tinnitus(-) mice. Each data point represents population mean ± SEM. Open circles represent a significant difference from baseline and closed circles a non-significant difference from baseline (significance at p<0.05); <i>n</i> refers to the number of mice; *: p<0.05.