Abstract
An extensive literature has examined how the spatial nature of a distractor (i.e., proximal vs. distal) relative to a target influences the planning of goal-directed movements with direct stimulus-response (SR) relations (i.e., prosaccade and propointing). To our knowledge, however, no work has examined how the spatial location of a distractor influences the planning of an antipointing response; that is, a reaching movement directed 180° mirror-symmetrical to the location of a target stimulus. Indeed, such a question represents an important issue in the visuomotor control literature because it provides a basis for determining whether the sensory- and/or motor-related features of a distractor influence response planning. To that end, participants completed pro- and antipointing movements in a condition that entailed a single and briefly presented target (i.e., control condition), and conditions wherein the target was presented concurrently with a proximal (i.e., ipsilateral) or distal (i.e., contralateral) distractor. Results for pro- and antipointing showed that proximal and distal distractor types produced shorter and longer RTs than the control condition, respectively. Based on these findings, we propose that the spatial relations between a distractor and movement-related goals for antipointing elicits an inhibition of visuomotor planning mechanisms. Further, we propose that distractor interference in pro- and antipointing planning emerges when participants have to select between target and non-target stimuli that code for directionally alternative motor responses.Acknowledgments: Natural Sciences and Engineering Research Council of Canada (NSERC); Academic Development Fund and Faculty Scholar Awards from the University of Western Ontario