I-Corps: Translation Potential of a Deep Brain Stimulation of Motor Thalamus to Improve Speech Intelligibility for Dysarthria After Chronic Stroke

The broader impact of this I-Corps project is the development of an assistive neurotechnology device to improve speech and swallowing for patients with motor speech disorders and dysphagia. Currently, there are no existing technologies available to improve muscle weakness associated with dysarthric speech directly. With speech therapy alone, patients with moderate or severe dysarthria may see mild improvements using compensatory strategies but still suffer from impaired speech as oral-motor exercises used in therapy are typically unable to rebuild muscle tone or increase control over weak or paralyzed muscles. Additionally, augmentative and alternative communication devices (text-to-speech synthesizers, alphabet boards, etc.) exist to improve communication, but even when used consistently, do not restore natural speech, can be cumbersome to transport, and have functional limitations (e.g., for speaking over the phone). This technology, however, gives patients increased control over their facial and phonatory muscles and increased range-of-motion in their faces, leading to improved articulation and intelligibility of speech. This I-Corps project utilizes experiential learning coupled with a first-hand investigation of the industry ecosystem to assess the translation potential of the technology. This solution is based on the development of deep brain stimulation (DBS) of the motor thalamus brain region to enhance muscle activity and restore motor function. The solution uses existing Food and Drug Administration (FDA)-approved stimulation hardware, consisting of an electrode lead and implantable pulse generator to deliver DBS with novel stimulation settings and for the treatment of a new indication in the recovery of speech and swallowing function. Preclinical studies have demonstrated that DBS in the motor thalamus increases muscle activity in the face, arm, and hand of nonhuman primates. DBS of the motor thalamus during pilot testing allowed patients that had motor speech deficits stemming from traumatic brain injuries to generate clearer speech with improved articulation and intelligibility. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.