Fig. 5.

Effect of cochlear hearing loss on the frequency tuning of temporal responses to TFS and ENV information. Representative frequency tuning curves (top) of chinchilla auditory-nerve fibers with varying degrees of noise-induced hearing loss. Characteristic frequencies (CFs) ranged from 3 to 4 kHz. Wiener kernels (middle panels) show the temporal response to TFS information (1^st order kernels) and ENV information (filtered 2^nd order kernels). Frequency-domain representations of the kernels (bottom panels) show that control fibers in this CF range encode primarily ENV information (red) based on stimulus energy near CF. Mild hearing loss introduced additional phase locking to low-frequency TFS information (black curve), while with moderate impairment both the TFS and ENV information encoded were centered at lower frequencies well below CF.