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Description: Spontaneous broadband electroencephalography (EEG) demonstrates short moments of stability in the spatial distribution of the head-surface voltage topography. This phenomenon underlies the premise behind the segmentation of multichannel EEG into topographically defined brain states, known as EEG microstates. Microstate segmentation methods commonly identify representative topographical configurations based on clustering applied to a subset of voltage maps selected at the time series points of greatest strength in the neuroelectric field. These moments are well-reasoned to best represent periods of quasi-stability, and consequently, points of greatest signal relative to noise. Yet, more direct empirical evidence for these assumptions is valuable, and the consistency of this phenomenon across individuals has not been characterized. In the present investigation, the association between electric field strength and topographic dissimilarity of temporally adjacent samples of EEG was characterized in a large sample of healthy adults. Every individual demonstrated that samples of their EEG time series high in electric field strength were topographically similar relative to adjacent time series samples. The strong activity of phase-synchronized neuronal populations therefore coincide with periods of topographic stability, providing robust empirical support for the basic premise underlying segmentation of broadband EEG into microstates.