Anomalous anatomy of speech–language areas in adults with persistent developmental stuttering

Abstract

To the Editor: I read with interest the article by Foundas et al.,1 which is the latest in a line of neurologic reports that confuse the cause and effect of stuttering (stammering). The observations associated with this clinical problem of chronic involuntary blockage are not disputed. That these observations can be interpreted as a cause of blockage is neurologically impossible. Because unintended blockage of speech is an aberration of normal speech processing, which is a manifestation of synchronization of phonation (for speech power) with articulation (that shapes phonatory power into the sounds of speech), the essence of fluent speech is the timing of speech sound phonatory/articulatory synchronization. Any cause of blockage has to account for why it can be involuntary (otherwise it would never become chronic), and, more to the point, how high-speed speech sounds can be produced with low-speed, cognitive/linguistic equipment. Synchronization speed is revealed by the syllable rate (no sound can be produced outside the context of a syllable) multiplied by the number of sounds per syllable. Syllable and cognitive thinking rates turn out to be roughly the same, which is fortunate, otherwise we would be unable to speak at the same rates we think. Decades ago, George Miller demonstrated the cognitive rate to be 7 ± 2 per second.2 In 1964, I inadvertently discovered that this is also the syllable rate, when …