Effect of cue-target interval on audiovisual stimuli processing in endogenous spatial attention: An event-related potentials study

Previous studies indicated that the interstimulus interval (ISI) has effects on the visual or auditory stimulus processing. Utilizing the high temporal resolution of event-related potentials (ERPs), we combined the endogenous cue-target paradigm in which the central cue could completely predicts the target location with go/no-go task to investigate whether the ISI could affect the audiovisual (AV) stimuli processing. The results showed that the ISI had effect on the AV stimuli processing. Specifically, the mean amplitude of the late positivity components (220-260 ms & 400-500 ms) was larger in the long ISI (1800 ms) condition than in the short ISI (600 ms) condition, while the late negativity component (300-340 ms) was larger in the short ISI condition than in the long ISI condition. But the ISI had no effect on early ERPs components (P1 & N1) elicited by the AV stimuli. The ERPs results suggested that the ISI can affect the AV stimuli processing reflecting on the later components, but not on the earlier ERPs components.