Spatiotemporal dynamics of EEG microstates in four- to eight-year-old children: Age- and sex-related effects

Abstract

The ultrafast spatiotemporal dynamics of large-scale neural networks can be examined using resting-state electroencephalography (EEG) microstates, representing transient periods of synchronized neural activity that evolve dynamically over time. In adults, four canonical microstates have been shown to explain most topographic variance in resting-state EEG. Their temporal structures are age-, sex- and state-dependent, and are susceptible to pathological brain states. However, no studies have assessed the spatial and temporal properties of EEG microstates exclusively during early childhood, a critical period of rapid brain development. Here we sought to investigate EEG microstates recorded with high-density EEG in a large sample of 103, 4-8-year-old children. Using data-driven k-means cluster analysis, we show that the four canonical microstates reported in adult populations already exist in early childhood. Using multiple linear regressions, we demonstrate that the temporal dynamics of two microstates are associated with age and sex. Source localization suggests that attention- and cognitive control-related networks govern the topographies of the age- and sex-dependent microstates. These novel findings provide unique insights into functional brain development in children captured with EEG microstates.

Keywords: Age; Brain development; Children; EEG microstates; Resting-state networks; Sex differences.

Fig. 1

The four microstates. Note. Microstates were derived from a polarity-invariant clustering algorithm.

Fig. 2

Violin- and box-plots (left) and paired mean difference estimates plots (right) show differences in the means of the temporal parameters between microstates. Note. All post-hoc combinations of ANOVA comparisons were significant at p < .0001, Benjamini-Hochberg-corrected for 24 multiple comparisons. Vertical bars in the paired mean difference estimates plots represent the 95 % confidence interval of the paired mean difference estimates; numerical values are presented as the paired mean difference value [95 % confidence interval]. M1 = Microstate 1; M2 = Microstate 2; M3 = Microstate 3; M4 = Microstate 4.

Fig. 3

Statistically significant interactions between age and sex on the temporal parameters of microstate 4. Note. The shaded areas represent Johnson-Neyman regions of significance (i.e., the interval of ages for which the simple slope of sex significantly differed from zero at p < .05). Johnson-Neyman plots are provided in the Supplementary Materials.

Fig. 4

Neural sources of Microstates 3 and 4. Note. Sagittal slices (x plane) are presented as left (positive coordinates) to right (negative coordinates) parts of the brain. Coronal slices (y plane) are presented as anterior (negative coordinates) to posterior (positive coordinates) parts of the brain. Axial slices (z plane) are presented as inferior to superior parts of the brain.