Figure 1. Example stimuli for the different array types.

By rotating the elements of the contour condition (left column), the embedded contour perceptually disappears (middle column). Top row: Iso-oriented array, in which all elements surrounding the contour have the same orientation. Bottom row: Randomly-oriented array, in which the surrounding elements have a random orientation. Catch trials (right column) consist of the same stimuli with a small circle overlaid at a random location (here only illustrated for no-contour stimuli). Catch trials are not included in the analyses.