Factors affecting gaze position lag in multiple object tracking
Jiří Lukavský · ASEP · 2014
Previously, it has been shown the gaze position during Multiple Object Tracking is systematically lagging behind the scene content by approx. 100 ms. We ran additional experiments to investigate how the cognitive workload and predictability of objects’ movements affect the lag time. In Experiment 1 we manipulated the number of tracked objects (2 or 4). In Experiments 2a and 2b we manipulated the predictability of movements on the screen by adjusting the parameters of von Mises distribution from which the objects’ directions were sampled. All experiments confirmed the presence of gaze position lag of 100 ms when tracking 4 targets with speed 5 deg/s. We found a significant increase of lag in less predictable movements (by +33 ms). The observed changes in gaze position lag for lower cognitive workload (-14 ms) or more predictable movements (-19 ms) were not significant.