  It is proposed that the theory of dynamical systems offers appropriate tools
to model many phonological aspects of both speech production and perception. A
dynamic account of speech rhythm is shown to be useful for description of both
Japanese mora timing and English timing in a phrase repetition task. This
orientation contrasts fundamentally with the more familiar symbolic approach to
phonology, in which time is modeled only with sequentially arrayed symbols. It
is proposed that an adaptive oscillator offers a useful model for perceptual
entrainment (or `locking in') to the temporal patterns of speech production.
This helps to explain why speech is often perceived to be more regular than
experimental measurements seem to justify. Because dynamic models deal with
real time, they also help us understand how languages can differ in their
temporal detail---contributing to foreign accents, for example. The fact that
languages differ greatly in their temporal detail suggests that these effects
are not mere motor universals, but that dynamical models are intrinsic
components of the phonological characterization of language.
