Objective: To report the first case of bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) producing transformative improvement in severe speech-induced dystonic dysfluency at the stuttering-dystonia interface.

Background: Stuttering and focal dystonia share overlapping basal ganglia dysfunction, yet severe dystonic dysfluency responsive to DBS has not been reported.

Method: We present a case with video documentation and quantitative assessments. A 23-year-old man with childhood stuttering (age 9) achieved remission with speech therapy and metronome pacing at age 17. By age 20, speech attempts triggered severe motor phenomena: sustained leftward cervical deviation, facial grimacing, rapid blinking, lip tightening, and right hand dystonic posturing, occurring exclusively during speech. Rest and non-speech activities remained normal; written communication was fluent. Features demonstrated non-suppressibility, absence of premonitory urge, sustained posturing, and strict task-specificity consistent with segmental dystonia. Assessment documented blocks in >25% of utterances, mean block duration 29 seconds, speech rate 2.5 words/minute, and professional examination failure. MRI was normal. Clonazepam and trihexyphenidyl trials failed. Bilateral GPi DBS targeting ventral sensorimotor contacts was performed.

Results: Stimulation through bilateral ventral contacts produced near-complete resolution within 4 weeks. At 5-month follow-up, speech rate improved to >80 words/minute with <2% residual hesitations, complete upper limb dystonia resolution, and marked cervical/facial reduction. Functional communication was restored. No adverse effects occurred.

Conclusion: This first reported case establishes GPi DBS as effective treatment for severe speech-induced dystonic dysfluency. The dramatic response supports a dystonic mechanism and establishes GPi DBS as rational therapy when dystonic features are prominent and conventional therapies fail, with implications for diagnosis and neuromodulation strategies at the stuttering-dystonia interface.

References: 1. Kiziltan, G., & Akalin, M. A. (1996). Stuttering may be a type of action dystonia. Movement disorders: official journal of the Movement Disorder Society, 11(3), 278-282.
2. Simonyan, K., & Ludlow, C. L. (2012). Abnormal structure–function relationship in spasmodic dysphonia. Cerebral cortex, 22(2), 417-425.
3. Alm, P. A. (2004). Stuttering and the basal ganglia circuits: a critical review of possible relations. Journal of communication disorders, 37(4), 325-369
4. Quartarone, A., & Hallett, M. (2013). Emerging concepts in the physiological basis of dystonia. Movement Disorders, 28(7), 958-967.
5. Neumann, K., Euler, H. A., Bosshardt, H. G., Cook, S., Sandrieser, P., & Sommer, M. (2017). The pathogenesis, assessment and treatment of speech fluency disorders. Deutsches Ärzteblatt International, 114(22-23), 383.
6. Albanese, A., Bhatia, K., Bressman, S. B., DeLong, M. R., Fahn, S., Fung, V. S., … & Teller, J. K. (2013). Phenomenology and classification of dystonia: a consensus update. Movement disorders, 28(7), 863-873.

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MDS Abstracts - https://www.mdsabstracts.org/abstract/bilateral-gpi-deep-brain-stimulation-for-severe-speech-induced-dystonic-dysfluency-a-novel-phenotype-at-the-stuttering-dystonia-interface/