The deployment of visual attention during temporal integration: an electrophysiological investigation.

The deployment of attention during temporal integration was investigated with event-related potentials. Attentional selection of an integrated percept and an actual singleton were examined. Integration performance was related to modulations of the N2pc, N2, and P3 components. Singleton localization performance was reflected in N2pc and P3 only. Of note, the singleton N2pc developed and subsided earlier than the integration N2pc. The singleton P3 seemed to develop in a single deflection, while the integration P3 showed two more distinct deflections. Physical stimulus differences could not explain these results. The N2pc and N2 modulations showed that attending to an integrated percept is not slower per se, but does differ from attending to a singleton. Integrated percepts furthermore have special correlates in late stages of perception (i.e., the P3). These differences are linked to the unique demand to combine and represent successive stimuli.