The myoelastic-aerodynamic theory of sound production in humans, mammals, and birds

Authors: Christian Herbst

Abstract:

The myoelastic-aerodynamic (MEAD) theory of sound production was proposed over half a century ago, in order to explain how humans produce voice: via flow-induced self-sustained vocal fold oscillation: Once a proper pre-phonatory configuration is created, no further differ-entiated neural input is required in the larynx – the ensuing vocal fold vibration is a passive physical phenomenon. The MEAD theory has widespread applications to animal sound production: It applies not only to humans, but also to most non-human mammals (from bats to elephants, including non-human primates), extending across a remarkably large range of fundamental frequencies and body sizes, spanning more than five orders of magnitude. A recent publication provides empirical evidence that the MEAD theory is even relevant for birds, who, unlike humans and non-human mammals, produce sounds with a specialized organ, the syrinx. In this presentation the MEAD theory is reviewed, considering its overall relevance for hu-man communication in relation to (other) mammals. In particular, the potential for common physiological control mechanisms of voice source characteristics across multiple species is discussed.