Figure 1
A typical MOT trial. At the start of the trial, four identical objects flash in order to indicate that they are targets to be tracked. All objects then begin moving around the display. At end of the trial, the participant is required to click on the four targets.
Figure 2
Illustration of the trial procedure used in our study. Figure 2A shows an example of tracking fearful target faces among fearful distractor faces in the low-attentional load condition, while Figure 2B shows an example of tracking fearful target faces among neutral distractor faces in the high-attentional load condition. During the target cue phase, four groups of faces were arranged evenly along a large imaginary circle. Each group consisted of one target face and one distractor face, which were in turn distributed evenly on a small imaginary circle. The target faces to be tracked were flashed three times in order to highlight them to the participant. The target cues then disappeared and all faces began rotating. Two face groups rotated clockwise around their group center, and the other two rotated counter-clockwise. Each group simultaneously rotated around the screen center. During the response phase, all faces were occluded by grey rectangles. Participants were then shown each target face in turn and asked to click on its location.
Figure 3
Mean tracking accuracy in low- and high-attentional load conditions as a function of target and distractor facial expressions. (A) Results for location tracking. (B) Results for identity tracking. Error bars indicated ±1 standard errors.
Figure 4
Data from control experiment. Mean tracking accuracy in low- and high-attentional load conditions as a function of target and distractor facial expressions. (A) Results for location tracking. (B) Results for identity tracking. Error bars represented ±1 standard errors.