کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5045298 1370660 2016 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Hemispheric contributions to language reorganisation: An MEG study of neuroplasticity in chronic post stroke aphasia
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب رفتاری
پیش نمایش صفحه اول مقاله
Hemispheric contributions to language reorganisation: An MEG study of neuroplasticity in chronic post stroke aphasia
چکیده انگلیسی


- The MMN paradigm can be a useful tool to map neuroplasticity after stroke.
- Intensive language action therapy improves language in patients with chronic PSA.
- MMN enhancement for words after therapy correlates with language improvement.
- Perilesional regions in the left hemisphere contribute to language restitution.

Previous studies have demonstrated that efficient neurorehabilitation in post stroke aphasia leads to clinical language improvements and promotes neuroplasticity. Brain areas frequently implicated in functional restitution of language after stroke comprise perilesional sites in the left hemisphere and homotopic regions in the right hemisphere. However, the neuronal mechanisms underlying therapy-induced language restitution are still largely unclear. In this study, magnetoencephalography was used to investigate neurophysiological changes in a group of chronic aphasia patients who underwent intensive language action therapy (ILAT), also known as constraint-induced aphasia therapy (CIAT). Before and immediately after ILAT, patients' language and communication skills were assessed and their brain responses were recorded during a lexical magnetic mismatch negativity (MMNm) paradigm, presenting familiar spoken words and meaningless pseudowords. After the two-week therapy interval, patients showed significant clinical improvements of language and communication skills. Spatio-temporal dynamics of neuronal changes revealed a significant increase in word-specific neuro-magnetic MMNm activation around 200 ms after stimulus identification points. This enhanced brain response occurred specifically for words and was most pronounced over perilesional areas in the left hemisphere. Therapy-related changes in neuromagnetic activation for words in both hemispheres significantly correlated with performance on a clinical language test. The findings indicate that functional recovery of language in chronic post stroke aphasia is associated with neuroplastic changes in both cerebral hemispheres, with stronger left-hemispheric contribution during automatic stages of language processing.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Neuropsychologia - Volume 93, Part B, December 2016, Pages 413-424
نویسندگان
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