Sensation and Perception
How does your mind trick you?
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How does selective attention effect you?
 Focusing attention on one aspect of our experience
 Focusing on good looks and ignoring personality
 The gorilla on the basketball court
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How does figure & ground effect you?
 Figure = Foreground - what we focus on
 Ground = Background
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What do you see?
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What do you see?
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How your mind organizes information for you by grouping
 Proximity
 Similarity
 Continuity
 Connectedness
 Closure
 Seeing complete letters on
a sign even though some
bulbs are burned out.
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Depth perception
 Visual cliff
 Infants will stop at the
“cliff”
 The ability to perceive
depth is at least partially
innate.
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Do you remember?
 How does selective attention relate to the figure and
ground effect?
 What are the four ways your mind groups information to
help make sense of it?
 What is the visual cliff? What does it tell us about
depth perception?
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How does your brain organize your perceptions?
 Gestalt psychologists
 The whole is more than the sum of its parts
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How does your brain create perceptual illusions?
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How does your brain use linear perspective?
 Parallel lines converge
 E.g. Railroad tracks
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Why do we see motion when none is there?
 The perception of motion
 Phi phenomenon
 Apparent movement of stationary
lights
 Las Vegas marquees
 Stroboscopic movement
 Cartoon book flip pages
 Movies
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Which is larger?
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How do your eyes trick you with perceptual consistency?
 Ponzo Illusion
 A bar further away appears larger even if the same size on
our retinas.
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Do both your eyes see the same thing?
 Retinal Disparity
 Floating finger illusion
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Do you see what is actually there?
 Muller-Lyer Illusion
 Misperception of length of lines
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Do you remember?
 What is the Gestalt perspective?
 What are some examples of linear perspective?
 What two things help you see movement when none
exists?
 What is the ponzo illusion?
 What is retinal disparity? Can you give a
demonstration of it?
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Do your beliefs effect what you see?
 Perceptual set
 How do our beliefs affect our
perception?
 Definition of the situation
 We often perceive what we expect to
see
 Our mental predisposition influences
what we perceive
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How does the context effect what you see?
 What you see is affected by the context in which
you saw it.
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Human factor psychologists
 How can we organize machines to fit our natural
perceptions?
 How could this natural map be made even better?
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Human factor psychologists: Designing flight instrument
displays for pilots
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Extrasensory perception
 Telepathy
 Mind-to-mind communication
 Clairvoyance
 Perceiving remote events
 Precognition
 Perceiving future events
 Psychokinesis
 Mind over matter
 E.g. bending a spoon or raising a table
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Who has ESP?
 There is no reliable evidence that anyone possesses ESP.
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Do you remember?
 What is the Muller-Lyer illusion?
 What is perceptual set? How does it effect what we
perceive?
 What is the context effect? Can you give an example?
 What is an example of something human factor
psychologists would study?
 Why might a police department not want to use a
person with ESP to solve a crime?
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