Fig. 4.
Contra-noise suppression is normal in mice with mutations in the ACh receptors designed to block or enhance MOC effects. A: contra-noise effects in mice lacking the α9 ACh subunit: mean (±SE) ΔDPOAE from 8 runs in 3 mice; mean contra-noise level was 102 dB SPL. B: contra-noise effects mice lacking the α10 ACh subunit: mean (±SE) ΔDPOAE from 18 runs in 4 mice; mean contra-noise level was 99 dB SPL. For both panels, the ipsilateral f2 was at 16 kHz and primary levels were set to produce a DPOAE of 0 dB SPL.