The Clinical Outcome of Concurrent Speech Therapy and Transcranial Direct Current Stimulation in Dysarthria and Palilalia Following Traumatic Brain Injury: A Case Study

  • Masumeh Bayat shiraz university of medical sciences
  • Malihe Sabeti 3Department of Computer Engineering, Islamic Azad University, North-Tehran Branch, Tehran, Iran
  • K S. Rao Neuroscience Center, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), City of Knowledge, Panama City, Panama
  • Mohammad Nami Department of Neuroscience, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran
Keywords: traumatic brain injury (TBI), dysarthria, palilalia, transcranial direct current stimulation (tDCS), qEEG, speech therapy


Introduction: Dysarthria, a neurological motor speech disorder, is regarded as a common sequala of traumatic brain injury (TBI). Palilalia is a speech disorder characterized by involuntary repetition of words, phrases, or sentences. Based on the evidence supporting the effectiveness of transcranial direct current stimulation (tDCS) in some speech disorders, we hypothesized that using tDCS would enhance the expected speech therapy outcome in a case of TBI with dysarthria and palilalia. Method: The “Be Clear” protocol, a relatively new approach in speech therapy in dysarthria, together with tDCS were employed in this single case investigation. With respect to the tDCS montage, regions of interest (ROIs) were identified based on the comparative analysis of resting-state vs. speech task-concurrent qEEG results. Results: Measures of intelligibility, an important index in the assessment of dysarthria, were superior to the primary protocol results immediately and 4 months after intervention. We did not find any factor other than the use of tDCS to justify this superiority. Palilalia showed a remarkable improvement immediately after intervention but fell somewhat after 4 months. This might have been justified owing to the subcortical origin of palilalia. Conclusion: Our present findings suggested that applying tDCS together with speech therapy might be more effective in similar case profiles as compared to traditional speech therapy. This notion needs to be systematically investigated in well-designed parallel arm clinical trials.


Akbari, C., & Shollenbarger, A. (2016). Acoustics of palilalia: A case study. Paper presented at the Proceedings of Meetings on Acoustics, 29(1), 172ASA.

American Speech-Language-Hearing Association (ASHA). (2017). Traumatic Brain Injury (TBI). Retrieved from

Azevedo, J. C., Lopes, R., Curral, R., Esteves, M. F., Coelho, R., & Roma‐Torres, A. (2012). Clozapine‐induced palilalia? Acta Neuropsychiatrica, 24(2), 122–124.

Bai, Y., Xia, X., Kang, J., Yang, Y., He, J., & Li, X. (2017). TDCS modulates cortical excitability in patients with disorders of consciousness. NeuroImage: Clinical, 15, 702–709.

Baker, J. M., Rorden, C., & Fridriksson, J. (2010). Using transcranial direct-current stimulation to treat stroke patients with aphasia. Stroke, 41(6), 1229–1236.

Beukelman, D. R., & Yorkston, K. M. (1979). The relationship between information transfer and speech intelligibility of dysarthric speakers. Journal of Communication Disorders, 12(3), 189–196.

Bikson, M., Grossman, P., Thomas, C., Zannou, A. L., Jiang, J., Adnan, T., … Woods, A. J. (2016). Safety of transcranial direct current stimulation: Evidence based update 2016. Brain Stimulation, 9(5), 641–661.

Chang, S.-H., Choi, J., & Tseng, S.-C. (2017). Effects of tDCS on stepping reaction in healthy adults and individuals with chronic stroke. Brain Stimulation, 10(1), e4–e5.

Demirtas-Tatlidede, A., Vahabzadeh-Hagh, A. M., Bernabeu, M., Tormos, J. M., & Pascual-Leone, A. (2012). Noninvasive brain stimulation in traumatic brain injury. The Journal of Head Trauma Rehabilitation, 27(4), 274–292.

Devido-Santos, M., Gagliardi, R. J., Mac-Kay, A. P. M. G., Boggio, P. S., Lianza, R., & Fregni, F. (2013). Transcranial direct-current stimulation induced in stroke patients with aphasia: A prospective experimental cohort study. Sao Paulo Medical Journal, 131(6), 422–426.

Fletcher, S. G. (1972). Time-by-count measurement of diadochokinetic syllable rate. Journal of Speech and Hearing Research, 15(4), 763–770.

Gehrig, J., Wibral, M., Arnold, C., & Kell, C. A. (2012). Setting up the speech production network: How oscillations contribute to lateralized information routing. Frontiers in Psychology, 3(169).

Giraud, A.-L., Kleinschmidt, A., Poeppel, D., Lund, T. E., Frackowiak, R. S. J., & Laufs, H. (2007). Endogenous cortical rhythms determine cerebral specialization for speech perception and production. Neuron, 56(6), 1127–1134.

Hess, C. W. (2013). Modulation of cortical-subcortical networks in Parkinson's disease by applied field effects. Frontiers in Human Neuroscience, 7, 565.

Hustad, K. C. (2006). Estimating the intelligibility of speakers with dysarthria. Folia Phoniatrica et Logopaedica, 58(3), 217–228.

Hustad, K. C., Dardis, C. M., & Mccourt, K. A. (2007). Effects of visual information on intelligibility of open and closed class words in predictable sentences produced by speakers with dysarthria. Clinical Linguistics & Phonetics, 21(5), 353–367.

Kaiser, D. A. (2007). What is quantitative EEG? Journal of Neurotherapy, 10(4), 37–52.

Kwon, Y. G., Do, K. H., Park, S. J., Chang, M. C., & Chun, M. H. (2015). Effect of repetitive transcranial magnetic stimulation on patients with dysarthria after subacute stroke. Annals of Rehabilitation Medicine, 39(5), 793–799.

Landi, D., Benvenga, A., Quattrocchi, C. C., Vollero, L., Assenza, G., Pellegrino, G., … Tombini, M. (2012). Complex epileptic palilalia: A case report. Seizure: European Journal of Epilepsy, 21(8), 655–657.

Lauro, L. J. R., Rosanova, M., Mattavelli, G., Convento, S., Pisoni, A., Opitz, A., … Vallar, G. (2014). TDCS increases cortical excitability: Direct evidence from TMS–EEG. Cortex, 58, 99–111.

Ludlow, C. L., Hoit, J., Kent, R., Ramig, L. O., Shrivastav, R., Strand, E., … Sapienza, C. M. (2008). Translating principles of neural plasticity into research on speech motor control recovery and rehabilitation. Journal of Speech, Language, and Hearing Research, 51(1), S240–S258.

Maas, E., Robin, D. A., Hula, S. N. A., Freedman, S. E., Wulf, G., Ballard, K. J., & Schmidt, R. A. (2008). Principles of motor learning in treatment of motor speech disorders. American Journal of Speech-Language Pathology, 17(3), 277–298.

Marangolo, P. (2013). tDCS over the left inferior frontal cortex improves speech production in aphasia. Frontiers in Human Neuroscience, 7, 539.

Menon, D. K., Schwab, K., Wright, D. W., & Maas, A. I. (2010). Position statement: Definition of traumatic brain injury. Archives of Physical Medicine and Rehabilitation, 91(11), 1637–1640.

Miller, N. (2013). Measuring up to speech intelligibility. International Journal of Language & Communication Disorders, 48(6), 601–612.

Mitchell, C., Bowen, A., Tyson, S., Butterfint, Z., & Conroy, P. (2017). Interventions for dysarthria due to stroke and other adult‐acquired, non‐progressive brain injury. Cochrane Database of Systematic Reviews.

Monti, A., Ferrucci, R., Fumagalli, M., Mameli, F., Cogiamanian, F., Ardolino, G., & Priori, A. (2013). Transcranial direct current stimulation (tDCS) and language. Journal of Neurology, Neurosurgery, & Psychiatry, 84(8), 832–842.

Nilipour, R., Pour Shahbaz, A., Ghoreishi, Z. S., & Yousefi, A. (2016). Reliability and validity of Persian aphasia battery test. Iranian Journal of Ageing, 10(4), 182–191. Retrieved from

Park, S., Theodoros, D., Finch, E., & Cardell, E. (2016). Be clear: A new intensive speech treatment for adults with nonprogressive dysarthria. American Journal of Speech-Language Pathology, 25(1), 97–110.

Portnoy, R. A., & Aronson, A. E. (1982). Diadochokinetic syllable rate and regularity in normal and in spastic and ataxic dysarthric subjects. Journal of Speech and Hearing Disorders, 47(3), 324–328.

Rahimi-Movaghar, V., Saadat, S., Rasouli, M. R., Ghahramani, M., & Eghbali, A. (2011). The incidence of traumatic brain injury in Tehran, Iran: A population based study. The American Surgeon, 77(6), E112–E114

Robertson, B. D. (2001). Networked personal contact manager. U.S. Patent No. 6,269,369 B1. Washington, DC: U.S. Patent and Trademark Office.

Sparing, R., Dafotakis, M., Meister, I. G., Thirugnanasambandam, N., & Fink, G. R. (2008). Enhancing language performance with non-invasive brain stimulation—A transcranial direct current stimulation study in healthy humans. Neuropsychologia, 46(1), 261–268.

Speyer, R., Bogaardt, H. C. A., Passos, V. L., Roodenburg, N. P. H. D., Zumach, A., Heijnen, M. A. M., … Brunings, J. W. (2010). Maximum phonation time: Variability and reliability. Journal of Voice, 24(3), 281–284.

Stagg, C. J., & Johansen-Berg, H. (2013). Studying the effects of transcranial direct-current stimulation in stroke recovery using magnetic resonance imaging. Frontiers in Human Neuroscience, 7, 857.

Stocchetti, N., & Zanier, E. R. (2016). Chronic impact of traumatic brain injury on outcome and quality of life: A narrative review. Critical Care, 20(1), 148.

Van Borsel, J., Bontinck, C., Coryn, M., Paemeleire, F., & Vandemaele, P. (2007). Acoustic features of palilalia: A case study. Brain and Language, 101(1), 90–96.

Walshe, M., Peach, R. K., & Miller, N. (2009). Dysarthria impact profile: Development of a scale to measure psychosocial effects. International Journal of Language & Communication Disorders, 44(5), 693–715.

Wulf, G. (2013). Attentional focus and motor learning: A review of 15 years. International Review of Sport and Exercise Psychology, 6(1), 77–104.

Yakcoub, M. S., Selouani, S.-A., & O'Shaughnessy, D. (2008, March). Speech assistive technology to improve the interaction of dysarthric speakers with machines. Paper presented at the 2008 3rd International Symposium on Communications, Control and Signal Processing, St. Julians, Malta.

Yang, C.-C., Chung, Y.-M., Chi, L.-Y., Chen, H.-H., & Wang, Y.-T. (2011). Analysis of verbal diadochokinesis in normal speech using the diadochokinetic rate analysis program. Journal of Dental Sciences, 6(4), 221–226.

Yorkston, K., Beukelman, D., & Traynor, C. (1984). Assessment of Intelligibility of Dysarthric Speech (KIT). Austin, TX: PRO-ED, Inc.

Yorkston, K. M., Hakel, M., Beukelman, D. R., & Fager, S. (2007). Evidence for effectiveness of treatment of loudness, rate, or prosody in dysarthria: A systematic review. Journal of Medical Speech-Language Pathology, 15(2), xi-xxxvi.

You, D. S., Chun, M. H., Kim, D. Y., Han, E. Y., & Jung, S. E. (2010). The effects of transcranial direct current stimulation on dysarthria in stroke patients. Journal of Korean Academy of Rehabilitation Medicine, 34(1), 10–14.

Zhang, Y., Song, W., Du, J., Huo, S., Shan, G., & Li, R. (2017). Transcranial direct current stimulation in patients with prolonged disorders of consciousness: Combined behavioral and event-related potential evidence. Frontiers in Neurology, 8, 620.

Research Papers