The ASR and PPI responses are altered in the Isl1CKO. (A) ASR thresholds for BBN bursts and tone pips at 8, 16, and 32 kHz in control and Isl1CKO mice are shown. Holm–Sidak method multiple comparison t-test. *P < 0.05, **P < 0.01. (B) Significantly increased ASR latency to BBN is found in Isl1CKO compared to control mice; unpaired t-test, **P < 0.01. (C) Amplitude-intensity ASR functions for BBN stimulation and (D) for tone pips of 8 kHz and (E) 32 kHz at different decibel SPL intensities in control and Isl1CKO mice are shown. (F) Efficacy of the BBN, (G) 8-kHz, and (H) 32-kHz tone prepulse intensity on the relative ASR amplitudes are displayed; ASR ratio = 1 corresponds to the ASR amplitude without a prepulse (uninhibited ASR). Two-way ANOVA with Bonferroni post hoc tests. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. All data are expressed as mean ± SEM.