Abstract
In the current study we investigated whether visual attention can be simultaneously allocated to spatially distinct perceptual and saccade target locations, and how the split of attention influences discrimination performance and saccade parameters (i.e., accuracy, precision, and curvature). To this end, participants performed a same-different matching task during the preparation of a saccade. A central perceptual target cue instructed participants to covertly attend to one of three possible target locations. Thereafter, a central saccade target cue instructed them to perform a saccade either to the same (congruent) or a different (incongruent) location. The discrimination task appeared after the saccade target cue, in a time range of 0 – 120 ms. In incongruent trials, in which one discrimination target appeared at the perceptual target location and one at the saccade target location, participants matched the identity of both discrimination targets (i.e., same or different). In congruent trials, only one discrimination task had to be solved at the congruent perceptual and saccade target location; participants indicated the identity of the discrimination target (i.e., E or 3). Congruent trials served as baseline. Our results show that participants' matching performance was above chance; however, perceptual performance in the single discrimination task was clearly superior. Splitting attention also resulted in altered saccade performance: saccade accuracy as well as saccade precision declined compared to baseline, and saccades curved away from the covertly attended perceptual target location. Our findings suggest that participants are able to simultaneously allocate visual attention to multiple perceptual and saccade target locations. However, orienting attention away from the saccade goal interferes with saccade programming as suggested by altered saccade performance.
Meeting abstract presented at VSS 2016