Hcn1^−/− animals have delayed ABR latency. (A) Mean ABR thresholds for control and Hcn1^−/− animals at 6–7 wk of age. (B and C) Mean wave 1 (P1) amplitude (B) and mean wave 1 (P1) latency responses (C) evoked by 16-kHz tone pips delivered across increasing sound stimulus intensity. Note that Hcn1^−/− mice show delayed P1 latency relative to controls, whereas no significant difference was found in threshold (A) or amplitude (B). Error bars equal ±1 SEM. *, P < 0.05.