Eye fixation-related potentials in free viewing identify encoding failures in change detection

► Eye movements in the encoding stage of a change detection task do not distinguish between correct change detection and detection failure. ► Eye fixation-related potentials (EFRP) in fixation locations around relevant regions predict change detection success or failure. ► EFRP corresponding to saccade size lead to correct detection, no correspondence leads to incorrect detection. ► EFRP reflect encoding at locations of the next fixation target. ► Encoding failures in change detection result from deviation between eye movement and attention.