Figure 3.

The IDT. On each trial, participants were first presented with the reference illumination (2000 ms), followed by two comparisons (500 ms), separated by a short dark interval (400 ms). One comparison matched the reference (the target) while the other varied from the reference (the test). Participants were instructed to indicate which comparison was most similar to the reference via a button press. Colors shown in this figure are illustrative and do not represent the actual experimental stimuli.