Parsing attentional processes involved in the elicitation of the N2pc component

The elicitation of the N2pc event-related potential component is commonly thought to be related to attentional processes involved in the selection of lateralized target information. However, it has recently been suggested that this component may reflect the localization of visual information in preparation of selection processes. This hypothesis specifically proposes that processes responsible for localization, rather than the selection of target identity elicit the N2pc component. The present study sought to explore this hypothesis by using a paradigm in which a cue stimulus could initiate the localization process before the onset of a target in a lateralized rapid serial visual presentation stream. Results indicate that processing of a cue, designed to initiate localization in the absence of processing required for target identity selection, is sufficient to elicit the N2pc component. Further, the N2pc elicited by solo targets in this paradigm was not observed when targets were preceded by the spatially informative cue stimuli. These results support the localization hypothesis and may reconcile mixed results from previous research by addressing specific properties of cue stimuli.