Frontal lobe contribution to response inhibition process—an ERP study and aging effect

Abstract

Objectives: The aim of this study was to clarify activation areas during a Go/NoGo task using event-related brain potentials (ERPs), and to examine aging effects on the ERP components. Methods: Twenty-seven healthy volunteers were investigated with 128 channel recordings during a cued continuous performance test. The peak latency, amplitude, topographic distribution and neural sources of each ERP component were estimated with the low-resolution electromagnetic tomography (LORETA) on the grand average waveforms and ERPs from individual subjects. Results: Interpolated voltage maps over the scalp surface and LORETA images showed that the source of the P3 component for the Go condition was located at the bilateral parietal lobes. On the other hand, the NoGo-P3 source was observed mainly in the inferior anterior cingulate cortex and lateral orbitofrontal area. The source of the N2 component was located in the medial orbitofrontal area. The activities of the Go-P3, NoGo-P3 and NoGo-N2 in the old group showed relatively longer latencies and smaller amplitudes than the young group. Conclusions: Both the NoGo-P3 and NoGo-N2 have main electrical sources in the frontal lobe. The orbitofrontal area and the anterior cingulate cortex are the most important regions for the inhibitory control of behaviors. The activities of the Go-P3, NoGo-P3 and NoGo-N2 sources were decreased with age.