Subjective Contour: Apparent Depth or Simultaneous Brightness Contrast?

The perceptibility of subjective contour in a two-dimensional configuration is shown to vary systematically with the magnitude of simultaneous brightness contrast. Since prior work had suggested depth cues as the basis for subjective contour, depth cues were maintained in all configurations. However, depth cues failed to sustain the perception of subjective contour with a reduction in simultaneous brightness contrast.