The syllable in the light of motor skills and neural oscillations

Abstract

Recent advances in neuroscience have brought a great focus on how the auditory cortex tracks speech at certain time scales corresponding to pre-lexical speech units in order to achieve comprehension. In particular, it has been claimed that it is the syllabic rhythm to which slow neural oscillations in the auditory cortex entrain in order to chunk the speech stream into smaller informational units. However, the terms “syllable” and “rhythm” have been treated quite loosely in the current literature. We revisit classic approaches to show that both concepts do not necessarily have an acoustic or phonetic counterpart, which could be directly extracted by neural processes. We would like to suggest that the syllabic rhythm could emerge at the intersection of acoustic–phonetic and motor knowledge of speech. We furthermore propose that nesting of cortical oscillations might be the key mechanism to understand the timing constraints that lead to the emergence of the syllable.