Dataset Information

Functional Network Changes After High-Frequency rTMS Over the Most Activated Speech-Related Area Combined With Speech Therapy in Chronic Stroke With Non-fluent Aphasia.

ABSTRACT:

Objective

High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) to the lesional hemisphere requires prudence in selecting the appropriate stimulation spot. Functional near-IR spectroscopy (fNIRS) can be used in both selecting the stimulation spot and assessing the changes of the brain network. This study aimed to evaluate the effect of HF-rTMS on the most activated spot identified with fNIRS and assess the changes of brain functional network in the patients with poststroke aphasia.

Methods

A total of five patients received HF-rTMS to the most activated area on the lesional hemisphere, followed by 30 min of speech therapy for 10 days. The Korean version of the Western aphasia battery (K-WAB) and fNIRS evaluation were done 1 day before the treatment, 1 day and 1 month after the last treatment session. Changes of K-WAB and paired cortical interaction and brain network analysis using graph theory were assessed.

Results

Aphasia quotient in K-WAB significantly increased after the treatment (P = 0.043). The correlation analysis of cortical interactions showed increased connectivity between language production and processing areas. Clustering coefficients of the left hemisphere were increased over a sparsity range between 0.45 and 0.58 (0.015 < p < 0.031), whereas the clustering coefficients of the right hemisphere, decreased over a sparsity range 0.15-0.87 (0.063 < p < 0.095). The global efficiency became lower over a network sparsity range between 0.47 and 0.75 (0.015 < p < 0.063).

Conclusion

Improvement of language function and changes of corticocortical interaction between language-related cortical areas were observed after HF-rTMS on the most activated area identified by fNIRS with combined speech therapy in the patients with poststroke aphasia.

SUBMITTER: Chang WK

PROVIDER: S-EPMC8866644 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Functional Network Changes After High-Frequency rTMS Over the Most Activated Speech-Related Area Combined With Speech Therapy in Chronic Stroke With Non-fluent Aphasia.

Chang Won Kee WK Park Jihong J Lee Ji-Young JY Cho Sungmin S Lee Jongseung J Kim Won-Seok WS Paik Nam-Jong NJ

Frontiers in neurology 20220210

<h4>Objective</h4>High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) to the lesional hemisphere requires prudence in selecting the appropriate stimulation spot. Functional near-IR spectroscopy (fNIRS) can be used in both selecting the stimulation spot and assessing the changes of the brain network. This study aimed to evaluate the effect of HF-rTMS on the most activated spot identified with fNIRS and assess the changes of brain functional network in the patients with poststrok ...[more]

PMID: 35222235

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Project description:BackgroundSmall clinical trials have reported that low-frequency repetitive transcranial magnetic stimulation (rTMS) might improve language recovery in patients with aphasia after stroke. However, no systematic reviews or meta-analyses studies have investigated the effect of rTMS on aphasia. The objective of this study was to perform a meta-analysis of studies that explored the effects of low-frequency rTMS on aphasia in stroke patients.MethodsWe searched PubMed, CENTRAL, Embase, CINAHL, ScienceDirect, and Journals@Ovid for randomized controlled trials published between January 1965 and October 2013 using the keywords "aphasia OR language disorders OR anomia OR linguistic disorders AND repetitive transcranial magnetic stimulation OR rTMS". We used fixed- and random-effects models to estimate the standardized mean difference (SMD) and a 95% CI for the language outcomes.ResultsSeven eligible studies involving 160 stroke patients were identified in this meta-analysis. A significant effect size of 1.26 was found for the language outcome severity of impairment (95% CI = 0.80 to 1.71) without heterogeneity (I2 = 0%, P = 0.44). Further analyses demonstrated prominent effects for the naming subtest (SMD = 0.52, 95% CI = 0.18 to 0.87), repetition (SMD = 0.54, 95% CI = 0.16 to 0.92), writing (SMD = 0.70, 95% CI = 0.19 to 1.22), and comprehension (the Token test: SMD = 0.58, 95% CI = 0.07 to 1.09) without heterogeneity (I2 = 0%). The SMD of AAT and BDAE comprehension subtests was 0.32 (95% CI = -0.08 to 0.72) with moderate heterogeneity (I2 = 32%,P = 0.22). The effect size did not change significantly even when any one trial was eliminated. None of the patients from the 7 included articles reported adverse effects from rTMS.ConclusionsLow-frequency rTMS with a 90% resting motor threshold that targets the triangular part of the right inferior frontal gyrus (IFG) has a positive effect on language recovery in patients with aphasia following stroke. Further well-designed studies with larger populations are required to ascertain the long-term effects of rTMS in aphasia treatment.

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Project description:PurposeBehaviorally, acquired apraxia of speech (AOS) is a multidimensional syndrome that the experienced clinician recognizes based on impaired articulation and abnormal temporal prosody. We conducted this study to determine the extent to which three core features of AOS-when defined quantitatively-distinguish categorically among aphasia with no or minimal speech sound involvement, aphasia with AOS, and aphasia with phonemic paraphasia (APP).MethodThe study involved retrospective analysis of 195 participants with stroke-induced aphasia. We used three quantitative measures (phonemic error frequency, distortion error frequency, and word syllable duration [WSD]) to divide the sample into four participant groups according to the most likely speech diagnosis: aphasia with minimal speech sound errors, AOS, APP, and a borderline group with mixed profiles. We then conducted nonparametric comparisons across groups for which the measures were not defined and visualized all three measures in a three-dimensional graph.ResultsThe measures distributed as multidimensional spectra rather than discrete diagnostic entities, and there was considerable behavioral overlap among participant groups. Thirty percent of participants presented with aphasia with minimal sound production difficulties, and they were statistically indistinguishable from the APP group on distortion frequency and WSD. Distortion frequency and WSD were in a borderline region between AOS and APP for 29% of participants. Compared to all other groups, participants with AOS produced significantly more errors that affected listeners' phonemic perception.ConclusionsThe results suggest that the current AOS-APP dichotomy has limited validity. We conclude that a continuous multidimensional view of speech variation would be a constructive perspective from which to understand how the left cerebral hemisphere produces speech and that quantitative and normed speech measures should be used to inform differential diagnosis in clinical settings.Supplemental materialhttps://doi.org/10.23641/asha.21807609.

Dataset Information

Functional Network Changes After High-Frequency rTMS Over the Most Activated Speech-Related Area Combined With Speech Therapy in Chronic Stroke With Non-fluent Aphasia.

Objective

Methods

Results

Conclusion

Publications

Functional Network Changes After High-Frequency rTMS Over the Most Activated Speech-Related Area Combined With Speech Therapy in Chronic Stroke With Non-fluent Aphasia.

Similar Datasets

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