Speaking is one of the most complex actions that we perform,
but nearly all of us learn to do it effortlessly. Production of fluent speech
requires the precise, coordinated movement of multiple articulators (for
example, the lips, jaw, tongue and larynx) over rapid time scales. Here we used
high-resolution, multi-electrode cortical recordings during the production of
consonant-vowel syllables to determine the organization of speech sensorimotor
cortex in humans. We found speech-articulator representations that are arranged
somatotopically on ventral pre- and post-central gyri, and that partially
overlap at individual electrodes. These representations were coordinated
temporally as sequences during syllable production. Spatial patterns of
cortical activity showed an emergent, population-level representation, which
was organized by phonetic features.