The Self-Organization of Speech Sounds

TL;DR

This paper demonstrates how a discrete, compositional speech code can self-organize in artificial agents through sensory-motor interactions, shedding light on the origins of human speech without pre-existing linguistic capacities.

Contribution

It introduces a mechanism for the emergence of speech codes in artificial agents based on self-organization, without assuming linguistic or social coordination.

Findings

Speech-like codes emerge from simple sensory-motor interactions.

Self-organization occurs through generic perception-production coupling.

Results suggest speech may have arisen via natural self-organizing processes.

Abstract

The speech code is a vehicle of language: it defines a set of forms used by a community to carry information. Such a code is necessary to support the linguistic interactions that allow humans to communicate. How then may a speech code be formed prior to the existence of linguistic interactions? Moreover, the human speech code is discrete and compositional, shared by all the individuals of a community but different across communities, and phoneme inventories are characterized by statistical regularities. How can a speech code with these properties form? We try to approach these questions in the paper, using the "methodology of the artificial". We build a society of artificial agents, and detail a mechanism that shows the formation of a discrete speech code without pre-supposing the existence of linguistic capacities or of coordinated interactions. The mechanism is based on a low-level model of sensory-motor interactions. We show that the integration of certain very simple and non language-specific neural devices leads to the formation of a speech code that has properties similar to the human speech code. This result relies on the self-organizing properties of a generic coupling between perception and production within agents, and on the interactions between agents. The artificial system helps us to develop better intuitions on how speech might have appeared, by showing how self-organization might have helped natural selection to find speech.