Fig 1.
Schematic of an example “same” trial in the Experiment 1 training task.
Targets were presented for decreasing durations (Δ: 417ms, 267ms, then 117ms) during training. Participants were instructed to ignore the color of the targets and judge only if the shapes of the targets are identical. In this example, the two targets are different colors but the same shape, requiring a “same” response. Training continued until the participant was able to perform above 70% accuracy with a 117ms presentation time across a single block of ten trials.
Fig 2.
Schematic of 3 example trials in Experiment 1 with a colored distractor.
Participants judged whether the peripheral targets were the same shape, ignoring their colors, which were always different. The targets and the distractor were displayed for 117ms regardless of SOA. The central distractor appeared either (a) 267ms or 117ms prior to target onset, (b) simultaneously with target onset, or (c) 117ms or 267ms after target onset. In the examples shown, the targets are different colors but identical shapes and the correct response is “same”. (In Experiment 2, participants judged whether the targets were the same color, ignoring their shapes; for these displays in Experiment 2 the correct response would be “different”).
Fig 3.
The effect of a central distractor on peripheral color discrimination (mean d’) in Experiment 1.
A distractor appearing 117ms after target onset disrupted target discrimination sensitivity more than distractors appearing at every other SOA. Error bars represent 95% confidence intervals. Significant differences are discussed in text.
Fig 4.
The effect of a central distractor on peripheral color discrimination (mean d’) in Experiment 2.
Error bars represent 95% confidence intervals. Significant differences are discussed in text.
Fig 5.
Examples of stimuli used as targets in Experiment 3.
Exemplars differed by 30°, so that, for example, (a) and (b), (b) and (c), or (c) and (d) could be used as pairs. Only hue angle varied; luminance and saturation remained constant.
Fig 6.
The effect of a central distractor on peripheral color discrimination (mean d’) in Experiment 3.
Error bars represent 95% confidence intervals. Significant differences are discussed in text.