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Large arrows: the orientation of top-down attention to the stimulus, or away from it
Dashed curves: a continuum of states.
Thick lines with separators: a sharp transition between states. During subliminal processing, activation propagates but remains weak and quickly
dissipating. “Consciousness”: an approach trough visual neuroscience During preconscious processing, activation can be strong, durable, and can spread to
multiple specialized sensori-motor areas. When attention is oriented away from the
stimulus (large black arrows), activation is blocked from accessing higher areas and
establishing long-distance synchrony.
During conscious processing, activation invades a parieto-frontal system, can be
maintained ad libidum in working memory, and becomes capable of guiding
intentional actions including verbal reports.
The transition between preconscious and conscious is sharp. 15 Consciousness and visual pathways V1 is necessary for conscious vision (cf cortical blindness).
V1 is not sufficient for “conscious” vision (sensation).
(V1 may be active in vegetative state) Consciousness and visual pathways Dorsal route:
Unconscious Consciousness and visual pathways V5
(MT) Consciousness and visual pathways Potential
features Ventral route:
Conscious Recognition The classical view: dorsal ~ unconscious, ventral ~ conscious Neglect
Recognition Neurology: neglect bridging the dorsal and ventral streams 16 Consciousness and visual pathways
OFC orbitofrontal cortex
IT inferior temporal cortex
LSF low spatial frequency V1
Recognition Neurological view: attention as a bridge between Consciousness and visual pathways • No single area, pathway or locality appears to be the neural
correlate for (visual) consciousness. Adapted from
Journal of Cognitive Neuroscience
2003, 15, 600-9 -A partially analyzed version of the input image (V1) (i.e., a blurred image) is
projected rapidly from ea...
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- Dorsolateral prefrontal cortex, Parietal lobe, L. Crevits