Visual Processing and Topdown processing
• We have a very biased view of the world as a result of our quickly operating systems
• Ie: Chess pieces being the same colour but appear black/white
We are biased to assume the world is experienced the same!!
• The wavelengths of magnetic images that we can detect and see
• Humans cannot see all wavelengths
• Infrared: humans don’t see—but we can perceive them (our interpretation of infrared =
heat on skin)
o Rattlesnake sees infrared
Bias: Limits of visual detection shape your view of the world
• When you wear infrared glasses you can see heat and where it came from
Bias: Colours around you are just in your head
Why is colour information important?
• Camouflage▯environmental strategies
• Advertising brightly may scare predators off to show that he is poisonous
Adaptive Significance: Foraging Hypothesis
• Marmoset: 2 basic colour perception (di and trichromats)
o Tri: bright red fruit pops out
o Di: cannot see bright red fruit
Experiment: marmoset ▯ 2 varieties in field
• Will the trichromat have an advantage in finding coloured kix cereal? YES! They beat
Why is this important?
▯ daptive significance
• Facial hue hypothesis
• What differs faces to make them more attractive
• Higher estrogen count faces have more red faces!
o Adding blue—adding red – redness is better in women
o Higher estrogen= greater fertility
Unique combined receptor activity produces distinct colour perception