Seeing Inside Stuttering: A New Method to Study How Speech Flow Gets Disrupted

What is it about?

We developed a better way to study what happens in the articulation when people stutter. While most stuttering research relies on what we can hear, we wanted to see what's actually happening with the tongue, lips, and other speech organs during stuttering moments. Our method combines real-time structural MRI technology with specially designed speech tasks. Real-time MRI provides "movies" of all speech organs in action, while our speech tasks incorporate factors known to increase stuttering—like long sentences, conversation, and time pressure. This approach successfully captured over 100 stuttering moments from each participant we have tested, including different types (repetitions, prolongations, blocks) and different sounds.

Why is it important?

Articulatory studies of stuttered speech were challenging for two reasons: First, we needed special technology to see inside the mouth during speech. Second, people who stutter often become more fluent in laboratory settings, making it difficult to capture stuttering moments. Our methodology addresses these two problems by combining real-time structural MRI with naturalistic speech tasks. The collected real-time MRI vocal tract videos reveal meaningful articulatory behaviors during stuttering that are not detectable via acoustics alone. For example, during silent blocks, we could see the tongue and lips positioned for upcoming sounds, suggesting that speech planning remains intact even when speech execution is disrupted. This combined methodology opens new possibilities for understanding the articulatory mechanisms of stuttering. In addition to real-time MRI, the designed speech tasks have the potential to be combined with other experimental instrumentation to facilitate collecting other neurophysiological data during stuttered speech.