Attention-sensitive visual event-related potentials elicited by kinetic forms

Previous event-related potential (ERP) studies have shown that selectively attending to a relevant stimulus feature was associated with selection nega tivity (SN) components. The present study aimed at investigating the ERP in dices of attentional selection based on forms defined by motion (kinetic fo rms). ERPs were recorded from subjects who attended selectively to sequenti ally presented kinetic forms of bars in one visual field and detected occas ional tilted bar targets. Two kinds of kinetic forms were used as the visua l stimuli in separate experiments. The main findings were that spatial atte ntion enhanced the amplitude of early ERP components P1 and N1 as well as t he late component N2. Topographic maps of voltage and low resolution electr omagnetic tomography (LORETA) of the dN2 wave (difference waveform between N2 under attended condition and N2 under unattended condition) suggested an origin in the right occipitotemporal cortex. According to its timing and m orphology, the dN2 wave was considered to be an endogenous ERP (like the SN ) and was interpreted as reflecting attentional facilitation of the process ing of forms defined by motion primarily involving the right occipitotempor al areas. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.