The electrophysiological correlates of the size incongruity effect.

The size incongruity effect refers to an increase in response time when the physical size of the letters in which the name of an object is written conflicts with the actual size of the object named. The electrophysiological correlates of the size incongruity effect were investigated in 13 healthy individuals through event-related potentials in this study. Scalp event-related potential analysis revealed: the incongruent condition elicited two more negative components N200-400 and N500-700 than did the congruent condition. N200-400 is a critical sign of conflict detection in the early stage, whereas N500-700 mirrors the response conflict in the late stage. The results provided evidence for the dissociation between conflict detection and conflict resolution in the size incongruity effect.