Introduction to Cognitive Science
Computational Theories of Consciousness

Vision

Last Update: 2 September 2011

Note: NEW or UPDATED material is highlighted


For instructions on how to access articles from certain journals (notably Psychological Review) from buffalo.edu machines,
link to: "Classic (Online) Readings in Cognitive Science"


"The ‘magic’ of consciousness is that we think we are experiencing the world through our eyes and ears, but really everything is seen and heard in the brain."


"Reality is a tape-delayed broadcast, carefully censored before it reaches us."


"Our perceptions…are fantasies we construct that correlate with reality."


"Your brain, after all, is encased in darkness and silence in the vault of the skull. Its only contact with the outside world is via the electrical signals exiting and entering along the super-highways of nerve bundles. Because different types of sensory information (hearing, seeing, touch, and so on) are processed at different speeds by different neural architectures, your brain faces an enormous challenge: what is the best story that can be constructed about the outside world?"


"My phenomenal world…[is] a neural fiction perpetrated by the senses."


"It is a gross mischaracterization to say that we simply open our eyes and take it all in; what we are in contact with is a constructed product of many different brain processes."


  1. The visual system in the brain:

    1. retina

      • Figure 06-03. The eye. (a) Illustration showing how objects in the environment are physically projected to the back of the eye&151;the retina. (b) The eye and a cross-section of the retina. The cross-section of the eye shows where the photoreceptors are located in the retina. Both the rods and cones are shown. They respond to different types of light. The neural signal then travels via bipolar cells and then to the ganglion cells. The axons of the ganglion cells take the neural information out of the eye and backward toward the cortex. Source: Squire et al., 2003.

    2. from retina to cortex

      • Figure 06-07. The visual pathways from retina to cortex. (a) Example of a brain slice from a functional magnetic resonance imaging (fMRI) scan, showing the lateral geniculate nucleus (LGN) and primary visual areas at the back of the brain (the occipital cortex). The two different colors denote the two hemispheres of the brain. (b) Schematic illustration showing the visual pathways from the retina in the eyes to the primary visual cortex at the back of the brain. You can see here that the neural information from the nasal or inner sides of the eyes crosses over at the optic chiasm, to be processed in the contralateral side of the brain. The left visual field, in blue, is processed by the right visual cortex (also blue). The LGN, displayed in green, relays the visual information to the primary visual areas of the cortex. Source: Squire et al., 2003.

    3. hierarchy of visual processing

      • Figure 06-10. The hierarchy of visual processing. A demonstration of the hierarchical response properties of the visual system to simple and complex stimuli. The leftmost column shows our house stimulus and what receptive fields of each visual area we would see in the balloons. Not only do the receptive field sizes increase in each visual area, but also the complexity of the shapes they respond to. The rightmost column shows an estimate of where each area is in the brain. You can see that early visual areas respond to simple features and, as we move along the processing stream, areas respond to more complex shapes and objects. This is a well-established theme of the visual system.

  2. From "Neuroscience and Behavior Links" at UB's "Neuroscience and Behavior Explore—Learn—Enjoy" page:

  3. NEW
    Lamb, Trevor D. (2011), "Evolution of the Eye", Scientific American 305(1) (July): 64–69.

  4. How Saturn with its rings looked to early astronomers

  5. Gibson, James J. (1979), The Ecological Approach to Visual Perception (Boston: Houghton Mifflin).

  6. Fodor, Jerry A.; & Pylyshyn, Zenon (1981), "How Direct is Visual Perception? Some Reflections on Gibson's 'Ecological Approach' ", Cognition 9: 139-196.

  7. Marr, David (1982), Vision: A Computational Investigation into the Human Representation and Processing of Visual Information (New York: W.H. Freeman).

  8. Biederman, Irving (1987), "Recognition-by-Components: A Theory of Human Image Understanding", Psychological Review 94: 115-147.

  9. Gregory, Richard L. (1997), Eye and Brain: The Psychology of Seeing, 5th Edition (Princeton, NJ: Princeton University Press).

  10. Simons, Daniel J. (2005), Visual Cognition Lab

  11. Changizi, Mark A.; Hsieh, Andrew; Nijhawan, Romi; Kanai, Ryota; & Shimojo, Shinsuke (2008), "Perceiving the Present and a Systematization of Illusions", Cognitive Science 32(3) (April-May): 459–503.

  12. Cyclopean vision example



Copyright © 2007–2011 by William J. Rapaport (rapaport@buffalo.edu)
http://www.cse.buffalo.edu/~rapaport/575/vision.html-20110902
http://www.cse.buffalo.edu/~rapaport/719/vision.html-20110902