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A study of object-related activation shows that it is positioned at the occipital lobe's lateral posterior area, just touching the motion-sensitive area MT/V5s posterior aspect, in a region termed the lateral occipital complex (LO). Despite the preferential activation to objects, LO did not seem to be involved in the final recognition process stages but as an intermediate link.

Over half of the neocortex in nonhuman primates is occupied by visual areas. At least 25 visual areas beyond the primary visual cortex (V1) have been identified with a combination [...], The borders of human visual areas V1, V2, VP, V3, and V4 were precisely and noninvasively determined. Functional magnetic resonance images were recorded during phase-encoded retinal stimulation. This volume data set was then sampled with a cortical surface reconstruction, making it possible to calculate the local visual field sign (mirror image versus non-mirror image representation). This method automatically and objectively outlines area borders because adjacent areas often have the opposite field sign. Cortical magnification factor curves for striate and extrastriate cortical areas were determined, which showed that human visual areas have a greater emphasis on the center-of-gaze than their counterparts in monkeys. Retinotopically organized visual areas in humans extend anteriorly to overlap several areas previously shown to be activated by written words.

Several researchers have designed an experiment that suggests that visual awareness occurs at a higher stage than orientation-specific adaptation. The experiment involves the projection of a master image, oriented either horizontally or vertically, which is then slowly masked by other images. Subjects were unable to determine the original orientation of the master image. The results of the experiment support earlier assertions that the neural correlate of awareness lies beyond the V1 neurons.

Discusses the early stages of primate visual processing, which seems to be divided up into several component parts. Finding that further subspecialization occurs within the motion processing stream; Analysis of color, form and motion; Two major classes of neurons found in the middle temporal area (MT); More.

Discusses the implications of an experiment of visual awareness. The discovery that visual awareness must occur at a higher stage in the visual hierarchy than orientation-specific adaptation; The use of a common visual after-effect phenomenon; The possible mediation of the after-effect by oriented neurons in primary visual cortex (V1); The experiment by He and colleagues found in the September 26, 1996 issue of `Nature.'