Related Experiment Video
Updated: Sep 10, 2025

06:37
Electroencephalography Network Indices as Biomarkers of Upper Limb Impairment in Chronic Stroke
Published on: July 14, 2023
966
Entropy Analysis of Electroencephalography for Post-Stroke Dysphagia Assessment
Adrian Velasco-Hernandez1, Javier Imaz-Higuera1, Jose Luis Martinez-de-Juan1
1Centro de Investigación e Innovación en Biotecnología (Ci2B), Universitat Politècnica de València (UPV), 46022 Valencia, Spain.
Entropy (Basel, Switzerland)
|August 28, 2025
Summary
Sample Entropy (SampEn) analysis of electroencephalography (EEG) signals reveals altered brain activity in stroke patients with dysphagia. This complexity measure offers a potential biomarker for diagnosing swallowing difficulties after stroke.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Clinical Neurology
Background:
- Dysphagia affects over 50% of stroke patients, posing diagnostic and management challenges.
- Dysphagia is linked to disrupted cortical and subcortical neural activity, observable in electroencephalography (EEG) patterns.
- Sample Entropy (SampEn) measures signal complexity and can potentially identify dysphagia-related abnormalities.
Purpose of the Study:
- To identify quantitative dysphagia biomarkers using SampEn from EEG recordings in post-stroke patients.
- To investigate alterations in neural activity associated with swallowing in individuals with and without dysphagia post-stroke.
Main Methods:
- Calculated SampEn in theta, alpha, and beta EEG frequency bands during a repetitive swallowing task.
- Analyzed data from three groups: healthy individuals, stroke patients without dysphagia, and stroke patients with dysphagia.
- Utilized EEG, a non-invasive and cost-efficient neuroimaging technique.
Main Results:
- Post-stroke patients (with and without dysphagia) showed significant SampEn differences compared to healthy subjects in alpha and theta bands, indicating widespread brain dynamic alterations.
- A significant cluster in the left parietal region (beta band) during swallowing exhibited higher SampEn in dysphagic patients versus healthy individuals and controls.
- These findings suggest impaired sensorimotor integration and disrupted cortical coordination in dysphagia.
Conclusions:
- SampEn analysis of EEG signals provides a robust and objective biomarker for neurogenic dysphagia.
- This method can aid in the diagnosis of dysphagia and monitor therapeutic interventions.
- EEG-based SampEn quantification offers a cost-efficient approach to understanding and managing post-stroke swallowing impairments.

