Fig 10. Time-dependent effects of treatment on ABR threshold sensitivity.

After initial threshold stabilization, the reduced amplitudes of ABR wave I progressively recovered with increasing post-blast exposure time in the NAC/HPN-07 therapeutic treatment group (B.) but not in the vehicle treatment group (A.). ABR wave-I amplitudes were normalized with respect to mean values in age-matched, unexposed naïve controls. Mean (± SE) amplitudes in response to tone bursts at 80 dB SPL are shown, where n = 34–40 ears/group. Data were obtained at 4 and 8 weeks after blast exposure, respectively. Statistical significance was determined by paired t-test with Holm-Bonferroni correction: ⁺ p < 0.05, the simple effect of time at 8 and 24 kHz.