Fig. 2
From: Discovery of key whole-brain transitions and dynamics during human wakefulness and non-REM sleep
State timecourses of whole-brain network states and their association to polysomnography. a The figure shows the 19 HMM state timecourses describing each state’s probability of being active at each sample point of the fMRI sessions in the 18 participants that reached all four PSG stages. Below the HMM state timecourses are shown the independently obtained PSG sleep scoring (based on the simultaneously acquired EEG). The coloured overlay shows periods scored as wakefulness (red), N1 (white), N2 (blue) and N3 (green). The two dashed boxes highlight the HMM state timecourses and PSG scoring of two representative participants. Note, how the majority of HMM timecourses varied with the PSG stages, in highly consistent ways across participants. A few ‘sporadic’ HMM states, occurring mainly in a few participants, are also visible (e.g., states 11 and 12). b Quantifying the multivariate relationship between the HMM states and the PSG scoring, through the use of MANOVA, revealed a hierarchical grouping of the HMM states, in which wakefulness and N1 sleep were separated from N2 sleep, which in turn was separated from N3
