Shape perception and low-dimension fractal boundary contours

We have identified a class of stimuli which seem to tap into the basic human ability to identify and name shapes. Using computer-generated stimuli, we found that patterns with low fractal dimension contours evoked the perception of namable objects, and that this proportion is increased when a pre-attentive criterion for examining the patterns is used. Furthermore, this result holds whether the patterns are filled in shapes (e.g., cloud patterns) or simple edge contours.