Interaction Of Simple Pattern Elements In Stereopsis

Brightness pattern disparity mediated by arrays of letters in many of Kaufman's (1964) letter stereograms could produce stereopsis. The letters composing each half-view did not need to be identical in order for stereopsis to be elicited on the basis of brightness pattern disparity, but when the letter arrays were composed of identical random assortments of letters, the brightness pattern disparity was weak or ineffective. To investigate the possibility that the dissimilar geometric shapes of the letters were disrupting brightness pattern disparity, the letters carrying the brightness pattern were systematically impoverished by decomposing them into their basic parts, defined as vertical, horizontal, diagonal, and curved letter elements.