Neurorehabilitation of Central Speech Disorders in Patients After Stroke and Traumatic Brain Injury – The State of Knowledge and The Potential of Transcranial Direct Current Stimulation
DOI:
https://doi.org/10.15225/PNN.2025.14.3.6Keywords
aphasia, brain injury, neurorehabilitation, post-stroke rehabilitation, speech therapy, transcranial direct current stimulation (tDCS)Abstract
Aphasia is a complex neurological disorder resulting from brain damage, leading to significant deficits in speech, comprehension, reading and writing. It significantly reduces the patients’ life quality, contributing to social isolation, depression and reduced independence. Despite advances in speech therapy (SLT), many patients experience limited improvement. The aim of this paper is to analyze the current state of knowledge on the rehabilitation of central speech disorders, with particular emphasis on the use of transcranial direct current stimulation (tDCS) as a supplement to traditional speech therapy neurorehabilitation. A literature review was conducted, including studies published between 2014 and 2024 in the PubMed, Scopus, Web of Science, and Cochrane Library databases. Randomized controlled trials (RCTs), systematic reviews, and meta-analyses assessing the efficacy of tDCS in patients with post-stroke aphasia and other speech disorders were analyzed. The review focused on: Mechanisms of tDCS action in the context of neuroplasticity and language recovery, Therapeutic protocols (intensity, duration, electrode location), Clinical outcomes regarding the improvement of functional communication, speech fluency, and other language parameters. Additionally, data on the safety and adverse effects of tDCS were analyzed, based on retrospective reviews and clinical reports. Research shows that intensive speech therapy leads to improved functional communication and reduced aphasia. tDCS has been shown to support neuroplasticity processes, contributing to faster and more effective recovery of speech function. Combined therapy (tDCS and SLT) proved to be more effective than SLT alone. However, differences in tDCS protocols and individual patient response indicate the need for personalization of treatment. tDCS is a promising, non-invasive method for supporting the rehabilitation of speech disorders. Integration of tDCS with traditional neurorehabilitation methods can significantly improve the communication skills of patients with aphasia. Further studies are necessary to optimize stimulation parameters and develop standard clinical guidelines. (JNNN 2025;14(3):136–145)
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Copyright (c) 2025 Zofia Twardochleb, Marta Szczepańska, Adam Druszcz, Maciej Miś, Marcin Miś, Małgorzata Paprocka-Borowicz, Joanna Rosińczuk
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