Abstract
The current study recorded gaze fixations while participants (N=15) performed a bimanual reaching and placing task. The task was to place two small blocks in either separate (incongruent), or the same (congruent) target locations while moving away from or toward the body. The blocks were rotated either 45 or 90 degrees as they were transported to the targets. Participants were instrumented with 8 Optotrak IRED markers (i.e. left and right index fingers, thumbs, wrists and blocks) to track hand and block movements and an ASL Mobile Eye Gaze Tracking system to record fixation locations. Results show that when making movements towards the same goal, both hands had similar movement times (p=.313). However, when placing the blocks into two separate targets, the non-dominant limb had a significantly longer movement time (p<.001). Gaze data showed that these timing differences in the incongruent conditions reflect the need for participants to focus on individual blocks, primarily in the non-dominant hand. Further, when moving toward the body, movement times for congruent and incongruent conditions were similar (p=.288). However, when moving away from the body, incongruent movements took significantly longer than congruent target reaches (p=0.021). In conclusion, participants showed an increase in movement time and a focus of visual attention on the non-dominant hand when moving the object during incongruent trials. This effect was pronounced when moving away from the body.Acknowledgments: Research support NSERC (PJB)