(A) Mean value of the PTTs of HD patients at each specific frequency (n = 35 ears) and of the non-HD controls (n = 40 ears). The dotted line indicates the normal hearing level (25 dB HL). *P < 0.05, **P < 0.01, ***P < 0.001. Three ears of HD patients were excluded because of middle ear pathologies. (B) The 4F-PTAs of HD patients were significantly correlated with the total motors score of HD patients (P < 0.05, r = 0.5274; Pearson’s correlation). (C) The 4F-PTAs of HD patients (n = 19, P < 0.05, r = 0.4789) and non-HD controls (n = 20, P < 0.05, r = 0.5196) were associated with age. ABR thresholds of WT and R6/2 mice were measured by click (D) and tone-burst (E) stimuli at the ages of 7.5 and 10.5 weeks (n = 10 per group). Click ABR (F) and tone-burst ABR (G) analysis of WT (n = 4) and Hdh(CAG)150 (n = 6) mice at the age of 15 months. SPL, sound pressure level. *P < 0.05, **P < 0.01, ***P < 0.001.