Other Visual Processes 3.2.2

Question 1

What is an afterimage?

Answer 1

Image that continues to appear in the eye after prolong exposure.

Question 2

What are feature detectors?

Answer 2

Specialized neurons that respond to specific features of visual stimulus
(process different features simultaneously)

may respond to objects’ angle, size, shape, and color

(Hubel and Weisel discovered this)

Question 3

What is the opponent-process-theory?

Answer 3

The perception of color results from three opposing retinal processes
(explains afterimages, red & green color blindness)

1. red-green
2. yellow/blue
3. black/white
   Red creates an excitatory signal while green sends an inhibitory signal.

Yellow wavelength stimulates both red and green receptors and sends excitatory signals.

Blue wavelength sends inhibitory messages leading to slow firing.

People can only process one color of their pair at a time
(one is inhibited and the other is stimulated)

Question 4

What is parallel processing?

Answer 4

When different parts of your brain process different features of a visual stimulus all at once

Helps process visual information instantly

ex. seeing a familiar person or object

Question 5

What are supercell clusters?

Answer 5

Groups of neurons that respond to complex visual patterns

ex. looking at different objects stimulates supercell clusters

Question 6

What is the trichromatic color theory?

Answer 6

Explains that any color you perceive is the result of the three types of photoreceptors (cones)
red, green, & blue

Cones are sensitive to wavelengths

1. shorter wavelengths = blue hues
2. medium wavelengths = green hues
3. longwave lengths = red hues

lack in this = color blindness