The order of visual processing: "Top-down," "bottom-up," or "middle-out"

Abstract

This paper deals with the order in which different levels of form are recognized in a visual image. An experiment is reported in which the size of a tachistoscopically viewed image was varied. The results suggest neither an invariant "top-down" (gross shapes first followed by lower-order details) or "bottom-up" (the opposite) sequence. Rather, they seem to suggest a sort of "middle-out" sequence: forms at some intermediate level of structure having an optimal size or spatial-frequency spectrum are processed first, with subsequent processing of both higher and lower levels of form. © 1979 Psychonomic Society, Inc.