Developmental Changes in Sleep Oscillations during Early Childhood

Figure 2

Illustration of single events. For each event, the following data are illustrated: 10 s epoch of EEG data (derivation C3A2) and spectrogram with the detected events marked by a rectangle. The length of the horizontal rectangle indicates the duration of the event and its height the minimal and maximal frequency. The cross indicates the frequency f_events at the time of minimal damping. Color-coded spectrogram estimated using AR(8) models on overlapping 1 s segments (warmer colors denote higher power). Spectrograms start 0.5 s later and ends 0.5 s earlier due to the fact that a 1 s segment was moved through the data. All data are from children at 3 years. (a) Fast delta oscillations in REM sleep (same child shown in Supplementary Figure S); (b) fast delta oscillations in NREM sleep stage 2 (same child shown in Supplementary Figure S); (c) theta oscillations in NREM sleep stage 2 (same child shown in Supplementary Figure S); and (d) sleep spindles in NREM sleep stage 2 (same child shown in Supplementary Figure S) are illustrated.