Event-related potential responses to letter-string comparison analogies.

Previous studies have used analogy completion tasks (e.g., abe is to abf as ijk is to what?) to examine the event-related potential (ERP) parameters of analogical reasoning. In the present study, ERP responses to analogies were investigated using an analogy comparison task (e.g., is abe to abf as ijk is to ijl?), with a focus on structural evaluation. The results showed that the identical match task elicited an N2 component with smaller amplitude than that of the N2 component in the zero- and one-step consistent analogies, reflecting automatic match detection. The data also showed that there were significant differences in the N400 during the consistent and inconsistent analogies, which may reflect a delayed perceptual mismatch with semantic strategies. Moreover, one-step consistent analogies evoked smaller late positive component (LPC) amplitudes than that evoked by identical match or zero-step consistent analogies in the 500- to 800-ms time interval, and one-step inconsistent analogies elicited smaller amplitude LPCs than that elicited by zero-step inconsistent analogies in the 500- to 750-ms time interval, which suggested that LPCs reflected structure evaluation in analogy comparison tasks.