Role of articulation in speech perception: clues from production.

The relative roles played by signal properties and nonsignal information in speech perception are first examined. The evidence strongly suggests that phonetic percepts are never knowledge-innocent records of the raw signal. That conclusion is drawn not only about "higher" levels of language processing, but is seen to apply also to the perception of elementary phonetic stimuli. A review of a broad range of facts about production highlights the fact that speech production is adaptively organized. That circumstance suggests that the signal does not encode articulatory or acoustic/auditory invariants, but plays the role of supplementing the multimodal information already in place in the listener's speech processing system. It is accordingly proposed that phonetic signals are not invariants wrapped in "noise," but are products of listener-dependent adaptations that transform speech patterns in principled and, therefore, interpretable ways. Do listeners form speech percepts by way of intermediate articulatory representations? There seem to be strong both theoretical and methodological reasons to doubt that they do.