Neural Mechanism of Mammalian Vocalization

Localization of a pontine vocalization-controlling area in the squirrel monkey

Dear Dr. Jurgens:
Your presentation is very interesting because it remained me a result from the study of bat echolocation. For the reasons, the effective areas blocked with kynurenic acid were a part of the auditory system. In addition, the sound properties bloked by the injection was clucking/cackling /twitter type calls which were strongly frequency modulated. Therefore this pathway appear to provide a feedback loop which subserves only for the modulated sounds. Since the auditory-vocalization system was coupled in bats(Suga and Yajima, 1986), blocking feedback sounds may resulted in disruption of sound production. However, how could we explain the other sounds that were not blocked by the glutamate antagonist. It seems plausible to consider that frequency modulated sounds carry more important information than the non-modulated sounds does in the species specific communication. Do you have any comments on this, Dr. Jurgenes.

Reference: Suga N. and Yajima,Y. Auditory-vocal integration in the midbrain of the mustached bat: Periaqueductal gray and reticular formation. In the Physiological Control of Mammalian Vocalization. John Newman(Ed.) Plenum Press, New York, 1988

Sat Dec 12