Voice Production and Perception

The voice is a prime channel of communication in humans and other animals. Voices convey many kinds of information, including physical characteristics like body size and sex, as well as providing cues to the vocalizing individual’s identity and emotional state. Vocalizations are produced by dynamic modifications of the physiological vocal production system. The source-filter theory explains how vocalizations are produced in two stages: (a) the production of a sound source in the larynx, and (b) the filtering of that sound by the vocal tract. This two-stage process largely applies to all primate vocalizations. However, there are some differences between the vocal production apparatus of humans as compared to nonhuman primates, such as the lower position of the larynx and lack of air sacs in humans. Thanks to our flexible vocal apparatus, humans can produce a range of different types of vocalizations, including spoken language, nonverbal vocalizations, whispering, and singing.

A comprehensive understanding of vocal communication takes both production and perception of vocalizations into account. Internal processes are expressed in the form of specific acoustic patterns in the producer’s voice. In order to communicate information in vocalizations, those acoustic patterns must be acoustically registered by listeners via auditory perception mechanisms. Both production and perception of vocalizations are affected by psychobiological mechanisms as well as sociocultural factors. Furthermore, vocal production and perception can be impaired by a range of different disorders. Vocal production and hearing disorders, as well as mental disorders including autism spectrum disorder, depression, and schizophrenia, affect vocal communication.