Transcranial direct-current stimulation induced in stroke patients with aphasia
a prospective experimental cohort study
Keywords:
Aphasia, Stroke, Electric stimulation, Speech disorders, Language disordersAbstract
CONTEXT AND OBJECTIVE: Previous animal and human studies have shown that transcranial direct current stimulation can induce significant and lasting neuroplasticity and may improve language recovery in patients with aphasia. The objective of the study was to describe a cohort of patients with aphasia after stroke who were treated with transcranial direct current stimulation. DESIGN AND SETTING: Prospective cohort study developed in a public university hospital. METHODS: Nineteen patients with chronic aphasia received 10 transcranial direct current stimulation sessions lasting 20 minutes each on consecutive days, using a current of 2 mA. The anode was positioned over the supraorbital area and the cathode over the contralateral motor cortex. The following variables were analyzed before and after the 10 neuromodulation sessions: oral language comprehension, copying, dictation, reading, writing, naming and verbal fluency. RESULTS: There were no adverse effects in the study. We found statistically significant differences from before to after stimulation in relation to simple sentence comprehension (P = 0.034), naming (P = 0.041) and verbal fluency for names of animals (P = 0.038). Improved scores for performing these three tasks were seen after stimulation. CONCLUSIONS: We observed that excitability of the primary motor cortex through transcranial direct current stimulation was associated with effects on different aspects of language. This can contribute towards future testing in randomized controlled trials.
Downloads
References
Martin PI, Naeser MA, Ho M, et al. Overt naming fMRI pre- and post- TMS: Two nonfluent aphasia patients, with and without improved naming post-TMS. Brain Lang. 2009;111(1):20-35.
Williams JA, Imamura M, Fregni F. Updates on the use of non-invasive brain stimulation in physical and rehabilitation medicine. J Rehabil Med. 2009;41(5):305-11.
Zaghi S, Heine N, Fregni F. Brain stimulation for the treatment of pain: A review of costs, clinical effects, and mechanisms of treatment for three different central neuromodulatory approaches. J Pain Manag. 2009;2(3):339-52.
Fritsch B, Reis J, Martinowich K, et al. Direct current stimulation promotes BDNF-dependent synaptic plasticity: potential implications for motor learning. Neuron. 2010;66(2):198-204.
Brunoni AR, Nitsche MA, Bolognini N, et al. Clinical research with transcranial direct current stimulation (tDCS): challenges and future directions. Brain Stimul. 2012;5(3):175-95.
Nitsche MA, Paulus W. Excitability changes induced in the human motor cortex by weak transcranial direct current stimulation. J Physiol. 2000;527 Pt 3:633-9.
Nitsche MA, Liebetanz D, Lang N, et al. Safety criteria for transcranial direct current stimulation (tDCS) in humans. Clin Neurophysiol. 2003;114(11):2220-2; author reply 2222-3.
Monti A, Cogiamanian F, Marceglia S, et al. Improved naming after transcranial direct current stimulation in aphasia. J Neurol Neurosurg Psychiatry. 2008;79(4):451-3.
Baker JM, Rorden C, Fridriksson J. Using transcranial direct- current stimulation to treat stroke patients with aphasia. Stroke. 2010;41(6):1229-36.
Flöel A, Rösser N, Michka O, Knecht S, Breitenstein C. Noninvasive brain stimulation improves language learning. J Cogn Neurosci. 2008;20(8):1415-22.
Iyer MB, Mattu U, Grafman J, et al. Safety and cognitive effect of frontal DC brain polarization in healthy individuals. Neurology. 2005;64(5):872-5.
Liuzzi G, Freundlieb N, Ridder V, et al. The involvement of the left motor cortex in learning of a novel action word lexicon. Curr Biol. 2010;20(19):1745-51.
Murase N, Duque J, Mazzocchio R, Cohen LG. Influence of interhemispheric interactions on motor function in chronic stroke. Ann Neurol. 2004;55(3):400-9.
Nowak DA, Grefkes C, Ameli M, Fink GR. Interhemispheric competition after stroke: brain stimulation to enhance recovery of function of the affected hand. Neurorehabil Neural Repair. 2009;23(7):641-56.
Hegde MN. Hegde’s Pocketguide to assessment in speech-language pathology. Toronto: Singular Thompson Learning; 2001.
Mac-Kay APMG, Assencio-Ferreira VJ, Ferri-Ferreira TMS. Afasia. In: Mac-Kay APMG, editor. Afasias e demências: avaliação e tratamento fonoaudiológico. São Paulo: Editora Santos; 2003. p. 47-59.
Ortiz KK. Afasia. In: Ortiz KK, editor. Distúrbios neurológicos adquiridos. São Paulo: Editora Manole; 2005. p. 47-64.
Lecours AR, Mehler J, Parente MA, et al. Illiteracy and brain damage--1. Aphasia testing in culturally contrasted populations (control subjects). Neuropsychologia. 1987;25(1B):231-45.
Kaplan EF, Goodglass H, Weintraub S. Boston naming test. 2nd ed. Philadelphia: Lea & Febiger; 1983.
Bertolucci PHF, Okamoto IH, Toniolo Neto J, Ramos LR, Brucki SMD. Desempenho da população brasileira na bateria neuropsicológica do Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) [Performance of Brazilian population in neuropsychological battery of Consortium to Establish a Registry for Alzheimer’s disease]. Rev Psiquiatr Clín (São Paulo). 1998;25(2):80-3.
Santos MD, Mac-Kay APMG, Gagliardi RJ. Study on language comprehension in aphasic subjects. Lengua y Habla. 2008;12(1):20-31. Available from: http://erevistas.saber.ula.ve/index.php/lenguayhabla/article/view/193/411. Accessed in 2013 (Mar 14).
Welsh KA, Ballard E, Nash F, Raiford K, Harrell L. Issues affecting minority participation in research studies of Alzheimer disease. Alzheimer Dis Assoc Disord. 1994;8 Suppl 4:38-48.
Meinzer M, Breitenstein C, Westerhoff U, et al. Motor cortex preactivation by standing facilitates word retrieval in aphasia. Neurorehabil Neural Repair. 2010;25(2):178-87.
Raymer AM, Singletary F, Rodriguez A, et al. Effects of gesture + verbal treatment for noun and verb retrieval in aphasia. J Int Neuropsychol Soc. 2006;12(6):867-82.
Fregni F, Boggio PS, Mansur CG, et al. Transcranial direct current stimulation of the unaffected hemisphere in stroke patients. Neuroreport. 2005;16(14):1551-5.
Boggio PS, Nunes A, Rigonatti SP, et al. Repeated sessions of noninvasive brain DC stimulation is associated with motor function improvement in stroke patients. Restor Neurol Neurosci. 2007;25(2):123-9.
Hummel F, Cohen LG. Improvement of motor function with noninvasive cortical stimulation in a patient with chronic stroke. Neurorehabil Neural Repair. 2005;19(1):14-9.
Datta A, Bansal V, Diaz J, et al. Gyri-precise head model of transcranial direct current stimulation: improved spatial focality using a ring electrode versus conventional rectangular pad. Brain Stimul. 2009;2(4):201-7, 207.e1.
