The experiment was carried out in a quiet and well‐lit electrophysiological room. All subjects were awake, relaxed, kept stationary, and sat comfortably in their chairs. Due to children with ASD had abnormal sensory behavior, we played cartoon clips to children in the process of wearing electrode cap and experiment preparation to stabilize their mood and improve coordination. The resting state EEG data were collected using 64‐channel of the event‐related potential recording system and PyCorder software (Brain Products) with a sampling rate of 500 Hz. All subjects wore 64‐channel acticap electrode cap (Brain Products). The electrodes were placed in accordance with the international 10–20 system (Klem, Luders, Jasper, & Elger, 1999), and the ground electrode was located between the Fp1 and Fp2 electrodes. We used bilateral mastoid electrodes as the reference electrodes and recorded vertical electrooculography (VEOG) and the horizontal electrooculography (HEOG) to monitor eye blink and eye movement signals. Impedance was set at less than 5 kΩ. All the children were asked to look at the green "+" in the middle of the black screen as long as possible during the EEG data acquisition process. A total of 2.5 min open‐eyes EEG data were obtained for each participant.
