(A) Representative traces from WT+ FA, CBS+/−, and CBS+/−+ FA mice in response to 16-kHz tone-burst stimuli at decreasing stimuli levels. In the WT + FA mice, multiple ABR peaks can be seen in response to the stimulus at levels down to 55 dB. In the CBS+/s− mice, number of ABR peaks at lower stimulus levels are minimum. (B) Hearing thresholds for click-evoked ABRs between WT, CBS+/− and CBS+/− +FA mice. *P<0.001 vs WT, #P<0.001 vs CBS+/−; n=3 animals/group.