Perception

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Perception

• Psychology 3906

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Introduction

• Why should we start here?
• Specializations at this level should lead to
  specializations of cognitive mechanisms
• Nice example of modularity

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Some examples

• Bats and sonar
• Snakes and IR
• Platypus and EM
• Bees and UV
• So two flowers that look the same to us, may look
  quite a bit different to a bee

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So..

• Some animals could have similar apparatus to us,
  however, environmental conditions may have
  created differences
• For example, great tits in Iran and the UK

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Physical leads to psychological

• Even the placement of the eyes in pigeons has
  lead to them having two foveas
• Those foveas serve separate systems (Roberts,
  Phelps, Macuda, Brodbeck and Russ, 1996)

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How can we study animal perception?

• Electrophysiology and single cell recording (e.g.
  Barry Frost)
• Behavioural change (e.g. Dan Weary)
• Animal psychophysics
• Clever experiments needed here
• Goldsmith et al and hummingbirds
• Foree and LoLordo, better get the right
  behaviour..

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We are just animals

• Quality
• Intensity
• JND
• Webers Law

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She didnt call it cognition, evolution and
behaviour for nothing

• Sensory neurons respond more to more intense
  stimuli
• More reliable behaviour to more intense stimuli
• Male songbirds with a larger repertoire are more
  successful!

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Signal Detection theory

• You know, hits, misses, false alarms etc
• The average looking male is less successful than
  the one that stands out

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Perception has driven evolution

• And vice versa
• Guppies
• Bright spots are sought out by females
• Oh and prawns
• Lots of predators, go with lots of red dots!
• Colonial vs. Solitary swallows

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Ahh but why oh swallow?

• Cant discriminate?
• No difference in calls?
• Sorta umm dumber?
• It is that there is no difference in the calls of
  the young

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Sexual selection

• WTF?
• Runaway selection
• Good genes
• Sensory bias
• Female preference shows up before the male
  characteristic

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Object recognition

• Features and conjunctions
• Pretty similar in people and pigeons
• Might be telling about a problem in the field,
  the search for cryptic prey

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Search Image

• Actual image?
• Might be the rate
• Reid and Shettleworth, 1992) found that it was
  probably the features
• Langley has found that it may depend on prey type
• If it is really hard to find food animals may
  slow down, especially if there is a predator
  nearby

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In sum

• Perception has affected evolution
• Evolution has affected perception