Effect of tracheosyringeal denervation on call in greenfinch (Carduelis sinica)

After sections of left or right tracheosyringeal nerve (NXIIts), greenfinch es may repeat everyday calls, with no effect on temporal properties. It is suggested that either side of syrinx may produce sound alone and ipsilatera l innervation of NXIIts for the syringeal muscles. After section of left NX IIts, the bird produces the vocal pattern of partial tone increase, and eff ects on the sound intensity and sentence length average 1.4 and 2.8 times t hose after section of right NXIIts, suggesting that the innervation of NXII ts has left side dominance. After bilateral section of NXIIts, the call rhy thm in company with expiratory motions is 98-146 times/min,on an average, a nd lose all sentence types and syllable structure of normal call. But the c all spectra produced by tympaniform membrane vibrations without innervation still reserve frequency components similar to the tonic frequency and harm onics of normal calls.