Electroencephalogram (EEG), which is known for its canonical and noninvasive advantages, is specialized in recording brain electrical activity generated by neurons and reveals brain connective characters. EEG includes delta (0.5–3.5 Hz), theta (3.5–7.5 Hz), alpha (7.5–12.5 Hz), beta (12.5–30 Hz), and gamma (30–100 Hz) frequency bands (Buzsáki & Draguhn, 2004). EEG power study pointed that 3‐month infants at high family risk of ASD show reduced frontal high‐alpha power (Levin, Varcin, O’Leary, Tager‐Flusberg, & Nelson, 2017). Resting state EEG studies in children and adults with ASD found widespread increased delta band power, including frontal lobe (Pop‐Jordanova, et al, 2010; Stroganova, et al, 2007), parietal lobe, and right temporal lobe (Chan et al, 2007). However, the largest reductions in absolute delta power in children with ASD are in the left frontal and posterior regions (Coben, Clarke, Hudspeth, & Barry, 2008). The difference of age may be the reason why the results of power spectrum of individual ASD are inconsistent, so the characteristics of resting power spectrum related to ASD still need to be further explored. EEG coherence, a main method of EEG
