Perception

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Perception

• Selective Perception
• Any moment our awareness focuses like flashlight
  beam on limited aspect.
• One estimate is our 5 senses take in 11 million
  bits of information per second, of which we
  consciously process about 40.
• Cocktail party effect. Ability to attend to one
  stimuli out of the millions available.

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Selective Perception

• At level of conscious awareness, our attention is
  divided. (driving - talking)
• Gorilla Videotape -- umbrella woman gt are
  examples of inattentional blindness
• Change Blindness
• Choice Blindness
• Some stimuli are so powerful we experience
  pop-out. Stimuli that demands our attention.

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Perceptual IllusionsThe Muller-Lyer illusion
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Perceptual Organization

• The Gestalt Laws of Organization
• Series of principles that focus on the ways we
  organize bits and pieces of information into
  meaningful wholes.
• Gestalt means whole

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Perceptual Organization

• The Gestalt Laws of Organization
• The whole is greater than the sum of its parts.
• Our brains do more than merely register info
  about the world. Not just like camera shutter
  letting things in. We constantly filter sensory
  information and infer perceptions in ways that
  make sense to us. Mind matters.

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Perceptual Organization

• Figure - Ground gt our first perceptual task is
  to perceive any object, called the figure, as
  distinct from the surroundings, called the
  ground.

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Gestalt Organization

• Closure - We fill in gaps to create a complete,
  whole object
• Proximity - We group nearby figures together

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Gestalt Organization

• Similarity - Figures that are similar to each
  other, we group together.

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Gestalt Organization

• Continuity - We perceive smooth, continuous
  patterns rather than discontinued
• Connectedness - when seeing things uniformed and
  linked, we see them as a single unit.

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Perceptual Organization Closure

• Gestalt grouping principles are at work here.

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Perceptual Organization Grouping Principles
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Depth Perception

• Seeing objects in 3 dimensions
• Two -dimensional objects fall on our retinas, yet
  we organize 3 dimensional perceptions.

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Perceptual Organization Depth Perception
Visual Cliff
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Depth Perception

• Retinal or binocular disparity.
• Retinas receive slightly different images. When
  brain compares these images, the difference
  provides important cues to the relative distance.

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Sensory RestrictionBlakemore Cooper, 1970

• Kittens raised without exposure to horizontal
  lines later had difficulty perceiving horizontal
  bars.

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Monocular Cues

• Relative size
• Interposition
• Relative clarity
• Texture Gradient
• Relative height

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Monocular Cues

• Relative Motion
• Linear Perspective
• Light Shadow

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Motion Perception

• Phi Phenomenon - When two adjacent stationary
  lights blink on-off in quick succession, we
  perceive movement or motion.

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Perceptual Interpretation

• Perceptual Adaptation
• (vision) ability to adjust to an artificially
  displaced visual field
• prism glasses
• Perceptual Set
• a mental predisposition to perceive one thing and
  not another

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Perceptual Adaptation

• What determines perceptual set? Through
  experience we form concepts or schemas, that
  organize interpret unfamiliar information.

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Is There Extrasensory Perception?

• Extrasensory Perception
• controversial claim that perception can occur
  apart from sensory input. Parapsychology
• Telepathy - mind to mind
• Clairvoyance -- Ability to gain information about
  person through a sixth sense
• Precognition -- Ability to predict future
  events
• Psychokinesis -- ability to control/move objects

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Joseph Campbell

• People say that what we're seeking is a meaning
  for life. I don't think that's what we're really
  seeking. I think that what we're seeking is an
  experience of being alive, so that we actually
  feel the rapture of being alive.