Cognitive control can modulate intersensory facilitation: speeding up visual antisaccades with an auditory distractor.
Résumé
Although saccadic reaction times to a visual stimulus are facilitated if an auditory accompanying stimulus is presented at the same location, this intersensory facilitation effect (IFE) has not been explored for antisaccades (saccades directed opposite to a visual target). In this study participants were asked to make an antisaccade opposite to a point of light presented right or left of fixation while accompanied by an auditory stimulus either at the same or at the opposite location with different stimulus onset asynchronies. Antisaccade reaction times for unimodal auditory and bimodal stimuli were shorter than for unimodal visual stimulation, in line with prosaccade studies. The auditory accompanying stimulus afforded antisaccade reaction times approximately as fast as prosaccades in the direction of a visual target, especially when it was presented 40 ms before the spatially congruent visual target. Moreover, predictiveness of the target position facilitated performance only when the auditory stimulus was presented at the opposite location and 40 ms before the visual target (interstimulus contingency effect). We conclude that intersensory facilitation is a mandatory, bottom-up process, but in the particular case of a response conflict due to a visual target, IFE can be shown to be modulated by the predictability of the target location.