Comparison of XE991 effects on VsEP (left) and ABR (right) peripheral response components. Response amplitudes (bottom) and latencies (top) are represented as a percentage of baseline; 100% indicates no drug effects on the responses, and 0% indicates elimination of responses following drug injection. For latencies, proportionate increases or decreases relative to baseline are indicated. Sampling for VsEP values were at 5-min intervals, whereas 15-min intervals were collected for ABR. Except for the highest dose, changes in ABR were more gradual than changes in VsEP. Different doses are color coded the same for all panels and marked where possible. Below 2.5 mg/kg at doses of 0.5 and 1.0 mg/kg, ABR amplitudes increased over the first 40 min following injection (rmMANOVA: 1 mg/kg: P1-N1, P = 1.7 × 10−5; P4-N4, P = 0.014; 0.5 mg/kg: P1-N1, P = 9.4 × 10−7).