Figure 7.

Vocoding effects on the MI_Population growth functions in each auditory structure. A–E, The curves display the average growth functions of the MI_Population for each structure in each vocoding condition (indicated by a gradient colors) in CN (A, in black), CNIC (B, in green), MGv (C, in orange), A1 (D, in blue), and VRB (E, in purple). In each structure, the vocoding slightly reduced the MI_Population values. At the cortical level, the reduction induced by vocoding was similar at 38 and 20 bands, then a stronger reduction was observed at 10 bands. At the thalamic level, there was almost no change in the growth function of the MI_Population with 38- and 20-band vocalizations, but there was a large decrease in MI_Population with the 10-band vocoded stimuli. In the CNIC, the vocoding only induced a reduction of the MI_Population for 20 and 10 bands; a similar scenario was observed at the CN level.