Vision and Brain - How we Perceive the World

James. V. Stone, University of Sheffield ... MIT Press 2012, ISBN-13 978-0262517737

PSU Library: BF241.S7 Multnomah County Central Library: 152.14 S8782v (2 copies)

2016/08: Amazon $34 new, Addall.com $15 used first chapter

A marvelous book, lucid and informative. Human eyes do not make a pixel grid image in the brain - they convert signals from 120 million receptors into 1 million information-compressed neural signals, representing color and contrast and edge differences. The signals split left and right, crossing over at the optic chiasm, pass through the lateral geniculate nucleus (LGN, the author has no explanation for this) and converge on the anterior striate cortex at the back of the brain. Some of the pre-LGN axons split off to drive the left and right lobes of the superior colliculus, which is involved in eye tracking.

• p83 - "the dumber the animal, the smarter the retina"
• p86 why an LGN? This six-layered system may (my hypotheses): (1) amplify the neural signal, reducing end-to-end propagation speed (2) adjust signal timing so that image wavefronts are synchronized at the striate cortex (3) allow reconnection of pathways to compensate for dead retinal or striate cells (4) block infection from eye to brain
• p89-110 occipital lobe, striate visual cortex V1 to V5, decreasing detail, increasing abstraction and interpretation
  • V1 Primary visual cortex 10 billion cells expand retinal data to orientation, texture, motion, contrast, depth, color, brightness
  • V2 Secondary visual cortex - binocular disparity
  • V3
  • V4 Color and shape
  • V5 Motion
• p109 inferotemporal cortex "Jennifer Annison cell" - feature maps associated in time
• p110 Leibnitz mill 1714: cannot understand whole system simply from the behavior of components
• p124 Bee dance "distance" wiggles are not geometric distance or time, but flow of optical texture
• p125 painted roadway stripes at shrinking distances encourage drivers to slow down
• p156 Charles Bonnet syndrome, damaged visual system "hallucinates" missing information

p178: Impressions

• Who is number one?

  • You are number six.

• What do you want?

  • Information.

• You won't get it.

  • Given that you had two alternatives, to agree or disagree to provide information, your negative response has just given us exactly one bit of information, thank you.

• Well, you won't be getting any more.

  • Given that you had two alternatives, to tell us you will or you won't provide more information, your response gives us another bit, thank you again.

• That's a low-down, two-bit trick to play.

  • We already knew that, so your response has given us no information.

• I'm glad to hear it.

  • Given that you had two alternatives, to be glad or not to be glad, your response gives us another bit; please continue.

• I can see that the only way for me not to provide information is to be silent.

  • Fair enough. Was that your final bit?

• It was.

  • Apparently not ...