RETRACTED: Simple mental arithmetic is not so simple: An ERP study of the split and odd–even effects in mental arithmetic

Abstract

This study aimed to investigate the effects of split size (small vs. large splits) and odd-even congruency (parity congruency vs. parity incongruency) of answers on arithmetical equation processing. Event-related potentials were recorded from 18 students in a first-answer-then-equation presentation mode. The ERP results showed that the odd-even congruency had a significant effect on the late positive wave in the small, but not the large split, with a late positive slow wave elicited by the small-split and the odd-even congruent conditions. This result suggests that the split effect has priority over parity congruency when both split and parity are at play simultaneously. Specifically, in non-retrieval arithmetic verification tasks, parity is modulated in cases where a direct judgment cannot be reached simply by depending on the split information.