Early vision is bottom-up, except for focal attention

It is the 30-year anniversary of the introduction of computer-generated random-dot stereograms and cinematograms in psychology (Julesz 1960). These stimuli, together with texture pairs with identical second-order statistics (Julesz 1962), are devoid of all familiarity cues and are briefly presented (followed by a mask), yet yield vivid depth, motion, and preattentive texture discrimination, respectively. This demonstrates that these perceptual processes must operate at an early stage in the central nervous system (CNS). Only in recent years was it established by Gian Poggio (1984) that global stereopsis (of dynamic random-dot stereog-rams) is extracted as early as layer IVB in V1, i.e., at the very input of the monkey cortex. Therefore, what I called originally "cyclopean " vision, I am now callin