High resolution event-related potentials analysis of the arithmetic-operation effect in mental arithmetic

Abstract

ObjectiveEarly, late and slow waves of event-related potentials (erps) appearing around 0–300ms, 300–500ms and after 500ms respectively post-question presentation have been differentially associated to mental arithmetic processing (MAP). We hypothesized that arithmetic-operation effect (AOE) will show greater modulation of early components (P100, P200) in high-frequency erps; late components (P300, N300) and slow waves in low-frequency ERP when large-size problems are employed. MethodsFourteen normal human subjects mentally processed large- and small-size addition, division, multiplication and subtraction problems. Spatiotemporal differences between these arithmetic-operations were studied by way of comparing amplitudes and latencies of early, late and slow waves. ResultsAll components were modulated by AOE. Modulated was observed as early as 100ms post-question presentation (in high-frequency ERP components). AOE was very pronounced in large-size problems (in low-frequency ERP components). ConclusionsResults suggest that modulation by AOE of ERP components is improved when large-size problems and low-frequency ERP components are employed. Thus, differentiation of neuropsychological processes manifested by amplitude and latency of ERP components may be best studied by first separating components into high- and low-frequency erps. SignificanceFindings raise the potential of obtaining ERP indices that may improve findings about the degree (and time) of engagement of cognitive processes (e.g. Strategy employed in MAP).