Figure 2. Denervation of the right syringeal muscles has little effect on the spectral features of song.

Spectrograms of Bengalese finch song before and after right tracheosyringeal nerve resection. The spectral features of the song are very similar following right nerve resection. Arrows to the left of to the mean spectrum illustrate that the peak energy content remains centered around 4 kHz following right syringeal denervation, which is in contrast to the effects of left NXIIts nerve resection.