Auditory Processing of Vocal Signals in Anurans

Abstract

Acoustic signaling between animals involves a rather remarkable cooperative communication channel. It enables rapid transfer of information over a considerable distance in which the sender and receiver need not be in visible contact, such as through dense foliage or in total darkness. The “information” within an acoustic signal is conveyed by the temporal and spectral pattern of sound pressure that the sender must control in order to transmit a “meaningful” message. The receiver, in turn, must possess a receptor apparatus that is sensitive to these incoming pressure variations as well as a nervous system that can decode them. But communication rarely occurs in isolation. In general there is an ambient background of other sounds from other sources that we collectively refer to as “noise” and that interferes with detection of those signals of interest. This is a universal problem that all animals face in communicating with other members of their own species.