Yara Mohiar¹ (), Rémy Allard¹; ¹Université de Montréal

When navigating within complex environments such as a crowded street, our focus of attention often rapidly shifts between objects. Given that attention generally shifts faster when it is triggered involuntarily (e.g., with an exogenous cue near the target) than voluntarily (e.g., with an endogenous cue pointing to the relevant target), we could expect that ignoring an exogenous cue would be more difficult than ignoring an endogenous cue. The current study compared the speed at which attention can be shifted when using exogenous and endogenous cues when having to shift their attention to a location opposite to the cued location (anti-cue). On each trial, eight gabors were simultaneously presented for 600 msec uniformly distributed along an annulus centered on the fixation point and randomly rotated clockwise or counter-clockwise by 30 degrees after 300 msec. Participants were asked to report the motion direction of the cued gabor (pro-cue) or of a target on the opposite location of the cued gabor (anti-cue). The cue was either exogenous (a circle around one of the gabors) or endogenous (an arrow at fixation pointing to a gabor). The time required to shift attention to the target location was measured using a staircase procedure controlling the duration between the presentation of the cue and the occurrence of the motion (i.e., cue onset asynchrony, COA). In the pro-cue conditions, the COA was significantly lower with an exogenous cue than an endogenous cue, as expected. In the anti-cue conditions, the COA was globally significantly higher than pro-cue conditions, but no significant difference between the type of cue (exogenous vs endogenous) was observed. These results suggest that it is similarly demanding to attend to a target located at the opposite side of the cued location when the cue is exogenous or endogenous.

Acknowledgements: This research was supported by a grant from the Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain (CRIR) to RA.