Figure 5. DPOAE in 6-month-old dwg/dwg mice present, but slightly reduced relative to +/+ and dwg/+ mice. Mean (+/− SEM, n shown in panels) distortion product otoacoustic emission (DPOAE) input/output functions from 6-month-old +/+, +/dwg and dwg/dwg mice at F2 frequencies of 13, 16, 24 and 30 kHz (thin dashed lines shows noise floor of system). DPOAE amplitudes for all three groups are well above the noise floor; DPOAE amplitudes for dwg/dwg mice are consistently smaller than those from +/+ and +/dwg mice.