Electroencephalogram features of visual working memory in the delay stage based on microstate analysis
10.3760/cma.j.cn121382-20241115-00107
- VernacularTitle:基于微状态分析视觉工作记忆延迟阶段的脑电特征
- Author:
Jinping SUN
1
;
Fengkai HE
;
Yunxiang WANG
;
Yuqi ZHU
;
Tiaotiao LIU
Author Information
1. 天津医科大学生物医学工程与技术学院，天津 300070
- Keywords:
Vision;
Working memory;
Electroencephalogram feature;
Microstate analysis;
Cluster analysis;
Global field power;
Global explained variance
- From:
International Journal of Biomedical Engineering
2025;48(1):41-46
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the electroencephalogram features of visual working memory in the delay stage based on microstate analysis.Methods:In this cross-sectional study, ten healthy male subjects aged 19-29 years old from Tianjin Medical University were selected from January to July 2015. The 32-channel electroencephalogram experimental data were recorded from these subjects during the visual working memory eye-open state for 10 min (resting-state) and the delayed matching-to-sample (DMS) task (task-state) conditions, respectively. After data pre-processing, a short-time Fourier transform was applied for time-frequency analysis to extract the characteristic time periods and frequency bands, and electroencephalogram microstates of the resting and task states of visual working memory were computed separately, using an improved k-means clustering algorithm. The Mann-Whitney U test was used to analyze the statistical differences between resting-state and task-state microstate parameters, including global field power (GFP), global explained variance (GEV), time proportion, mean spatial correlation, frequency of occurrence and duration. Results:The time-frequency distribution of the Fz channel in the responsible brain region in DMS task visual working memory showed that the energy was mainly concentrated in the theta band (4-8 Hz) during the delay stage (4.039-7.039 s). The bipolar locations of microstates A, B, C, and D were prefrontal and occipital, central frontal and occipital, right occipital and left frontal, and left occipital and right frontal, respectively. In microstates A and C, the mean spatial correlation of the task-state was both higher than that of the resting state. The comparison results for microstate A were (0.632 5±0.105 8 vs 0.624 5±0.461 4, P<0.05), and the results for microstate C were (0.589 4±0.233 4 vs 0.561 3±0.066 8, P<0.01). The parameters of the task-state microstate D were lower than those of the resting-state, including GFP (1.125±0.061 vs 1.277±0.741, P<0.05), GEV (0.077±0.061 vs 0.101±0.057, P<0.05), and time proportion (0.191±0.165 vs 0.224±0.094, P<0.05) and mean spatial correlation (0.561 2±0.211 6 vs 0.612 1±0.315 2, P<0.01). Conclusions:The critical period of visual working memory is the delay stage and the critical frequency band is the theta band. Microstate D is the characteristic feature of visual working memory in the delay stage of the theta band, and microstates A and C can also serve as its potential features.
