Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

Figure 3

Development of E-ABRs in the first 52 days postnatally. All animals are from the white cat colony, but only after hearing onset (after day 10 p.n.) CDCs can be differentiated from white cats with residual hearing. Stimulus: biphasic pulse, 200 μs/phase at 10 dB above threshold. Stimulus duration is shown as a black bar, the artifact is removed form the recordings. At day 3 p.n., even at this high stimulation intensity the amplitudes of the waves were very small and only two waves could be differentiated from noise (marked by arrows). At day 8 p.n., all waves were observed (at the high intensity shown, waves III–V fused into a single large wave marked by the asterisk).