Figure 1.

A visual representation of the stimuli presented in the order of their presentation in each experiment. Top, Experiment 1. A fixation is followed by the presentation of the first rectangle (here red), which can appear in any one of the four corners. This is followed by the presentation of a second (here slightly taller) rectangle (green) that appears in the opposite corner. The size, onset, and location of the two rectangles presented in each trial were randomized. In this example, the fixation mark is yellow, noting that the participant should report which item appeared first (TOJ); trials with a blue fixation prompted the reporting of which rectangle was more square (shape). Bottom, Experiment 2. Identical except that the rectangles are the same shape and initially have gray lines in them of differing widths. In this experiment, the shape discrimination was based on these brief gray bars. Importantly, the durations of the shape and TOJ tasks in experiment 2 were equivalent.