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Fig. 4 | Molecular Autism

Fig. 4

From: Abnormal coherence and sleep composition in children with Angelman syndrome: a retrospective EEG study

Fig. 4

Sleep spindles are reduced in children with AS. Power spectra from frontal electrodes a across all frequencies from 1 to 50 Hz and b focused on the sigma bandwidth. Data were re-analyzed from Sidorov et al. [6]. c Children with AS showed decreased spectral power in the low sigma (11–13 Hz) band in which sleep spindles occur. d Steps in automated spindle detection: the normalized signal (top) is filtered (middle) and Hilbert-transformed to calculate instantaneous amplitude (bottom). The upper threshold (red) was used to detect spindles, and the lower threshold (gray) was used to define spindle duration. e Automated detection—spindle rate (NT: n = 54, AS: n = 13) and duration (NT: n = 54, AS: n = 11) were decreased in children with AS. f Manual detection—spindle rates as detected manually by two experts who were blinded to genotype

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