Abstract
The mechanism of vocal cord motion while stuttering remains unclear. A study by Conture et al. (1977) presented 100% glottic closures with only a sample of six stuttering blocks. A larger study sample was required. This study examined 34 stuttering blocks through flexible fiberscopic imaging and mesurements by speech phonogram, airflows and voice waveforms. The percentage of glottic closure and glottic opening were about 50% and 50% respectively. Vocal cord positions varied from individual to individual while block were manifested. Our findings indicate the cause of stuttering in not to be larynx but rather in the brain.
