The Synapse

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Vision

• What do we call a cell that receives information
  from the environment? What is a transducer?
• We know what the information process in a neuron
  is. What is it in a cell that receives
  information from the environment?
• Rene Descartes the shape was carried in the
  neural pattern?
• What is information? One answer specific nerve
  energies (Johannes Muller) brain sees visual
  info, hears auditory info but nerves just send
  action potentials
• Hearing/sight and thalamus in ferrets.how did
  they test it?

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Vision

• Parts of eye

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Vision

• Parts of eye
• Receptor
• Bipolar
• Ganglion
• Optic tract
• Blind spot

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Vision

• Parts of eye

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Vision

• Parts of eye
• Macula 3 5 mm
• Fovea (acuity)
• Midget ganglion cells 1 to 1
• Convergence in periphery (summation)
• Acuity vs. light sensitivity

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Foveal and Peripheral Acuity

• X / / /
• X / / /

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Vision

• Parts of eye
• Rods
• Cones
• lines to the brain for rods vs cones? Why?
• Photopigments
• 11-cis-retinal (on opsins)
• 11-trans-retinal

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Vision

• Color perception
• Color and/or brightness what is information?
• How many colors can we see?
• How many types of cones do we need? (bands)
• Young-Hemholtz (trichromatic) theory
• Psychophysical observation people could
• see three colors using three kinds of cones
• Tuning, what is information?
• Colored dot on finger
• Which kind of tuning is more like gradients?

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Vision

• Parts of eye
• Equal color vision?
• Where is color?

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Vision

• Color vision, theory 2
• Opponent-process theory

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Vision

• Parts of eye
• Opponent-process theory
• Horizonatl cell
• An example of winner take-all
• Problems with it

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Vision

• Parts of eye
• Opponent-process theory
• Problems with it

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Vision

• Parts of eye
• Problems with it

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Vision

• Parts of eye

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Vision

• Parts of eye

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Vision

• Receptive fields
• Left hemifield goes to right hemisphere, and vice
  versa
• Where do the eyes cross?

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Vision

• Lateral inhibition
• How it works

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Vision

• Parts of eye

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Vision

• Parts of eye

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Vision

• Parts of eye