Validity and Reliability of Event Related Potential in Subacute Stroke

Abstract

The aim of this study was assess the test-retest reliability of the ERP and resting EEG test in subacute stroke patients. Additionally, we compared the validity of the EEG, ERP test to MMSE (Mini-Mental State Exam) and MoCA (Montreal Cognitive Assessment) to use it as an objective tool to evaluate cognitive function. We recruited 20 patients with subacute ischemic stroke who were 19 years of age or older and had an MMSE score of 20 or higher. All participants were tested K-MMSE (Korean Mini Psychostatistics Test) and K-MoCA (Korea-Montreal Cognitive Assessment). The resting-state EEG and P300 wave using an auditory and visual oddball paradigm were measured at baseline and once again in 24 hours. We calculated the brain symmetry index (BSI) and directional BSI (BSIdir) over different frequency bands and delta/alpha ratio (DAR). The intra-rater reliability and validity of the P300 latency, amplitude, BSI, BSIdir and DAR were measured by intra-class correlation (ICC) analysis and by Pearson`s correlation coefficient analysis, respectively. P300 latency showed excellent ICC level (auditory P contralesional, ICC = 0.918, visual P contralesional, ICC = 0.972, visual Pz, ICC = 0.945). In the visual ERP (latency), there was a significant correlation between Cz, C ipsilesional and Mini-Mental State Exam (MMSE) and C ipsilesional and Montreal Cognitive Assessment (MoCA). The P contralesional and Pz latency of visual ERP showed significant reliability, and the Cz and C ipsilesional of visual latency showed effectiveness in reflecting the cognitive function. Thus, these montages could be used as a basis for future studies.