Auditory temporal resolving power in birds

Abstract

There has long been the notion that bird song contains acoustic features, which are inaccessible to human listeners. Field and laboratory studies suggest that birds hear both the spectral and gross temporal features of bird song much like we do. But how precisely birds perceive their auditory world still remains somewhat of a mystery. Here, I review psychophysical studies that provide evidence that birds have an exquisite sensitivity to temporal fine structure in their vocalizations putting some aspects of bird vocalizations out of reach of human hearing. Work with zebra finches, in particular, shows that these birds are capable of discriminating between positive and negative Schroeder harmonic complexes at high fundamental frequencies. These birds can also discriminate temporal fine structure changes in their vocal signals that are well below human thresholds. Whether this ability is used for communication is still not clear but it could underlie the better-than-expected ability of birds to localize soun...