Figure 1.

Experimental apparatus and paradigm. A custom made mechanical device, pictured on top, lifted a set of shapes embedded on a disk to the index fingerpad of each participant. The three shapes, pictured below, were a square, a trapezoid, and a parallelogram. One shape was presented for each trial for three possible durations, 400, 600, and 800 ms. The schematic illustrates the time series of trials with shapes and durations occurring pseudorandomly. The dashed circles indicate the target stimuli for each condition.