Semantic relatedness between words in each individual brain: An event-related potential study

► The N400 was observed in the repeated exposure to the same word pairs. ► There were significant differences between the amplitudes of N400 elicited by semantically highly related, moderately related and unrelated conditions. ► The prominent N400 effect was revealed by a single-subject analysis adopting the semantic relationships of the participant's own judgment. ► Our single-subject analysis will clarify neural mechanisms of semantic networks consisting of multiple words in each individual.