Psycho pdf

• Selection


  Choosing which of many stimuli that will be processed
• Organization


  Collecting the information into some pattern
• Interpretation

  Understanding the pattern
• Perceptions can be in error
• Illusions


  Visual stimuli that are misinterpreted
• Skin senses


  Three basic skin sensations
• Basic skin sensations


  • Touch
  • Temperature
  • Pain
• Vestibular sense

  Sense of body orientation with respect to gravity and three dimensional space
• Vestibular sense

  • Semicircular canals provide the brain with balance information
• Kinesthetic sense

  Sensory system for body posture, orientation and movement
• Kinesthetic receptors


  • Found throughout the muscles, joints, and tendons of the body
• Sensory adaptation


  Repeated or constant stimulation decreases the number of sensory messages sent to the brain, which causes decreased sensation
• Sensory adaptation


  Repeated or constant stimulation decreases the number of sensory messages sent to the brain, which causes decreased sensation
• Sensory systems


  • Detect change within the environment
• Movement in the peripheral aspects of the eye


  May signal food or danger
• Constant pressure of an object on the skin may not be important
• Stimulus that moves across the skin


  May be a snake or a spider
• The skin adapts to constant pressure
• Absolute Threshold

  Smallest amount of a stimulus we can detect
• Difference Threshold


  Minimal difference needed to detect a stimulus change; also called the just noticeable difference (JND)
• Three Types of Processing

  • Transduction
  • Sensory Reduction
  • Coding
• Transduction

  Converts sensory stimuli into neural impulses that are sent on to the brain
• Sensory Reduction


  Filters and analyzes incoming sensations before sending on to the brain
• Coding


  Converts particular sensory input into a specific sensation sent to differing parts of the brain
• Sensation


  The process of receiving, converting, and transmitting information from the outside world
• Sensory organs

  • Contain receptors that transduce sensory energy into nerve impulses that are carried to the brain
• Selective attention


  Filtering out and attending only to important sensory messages
• Feature detectors


  • Specialized cells in the brain that respond only to certain sensory information
• Habituation is the tendency of the brain to ignore environmental factors that remain constant
• Gestaltists


  Proposed laws of organization that specify how people perceive form
• Figure and ground

  Basic organizational themes for perception
• Figure is perceived as distinct from the background
• Figure is closer to the viewer than the background
• Perceptual constancy


  The tendency for the environment to be perceived as remaining the same even with changes in sensory input
• Perceptual constancy

  • Size constancy
  • Shape constancy
  • Color constancy
  • Brightness constancy
• Depth perception


  The ability to perceive three-dimensional space and to accurately judge distance
• Binocular cues


  • Retinal disparity
  • Convergence
• Monocular cues

  • Linear perspective
  • Interposition
  • Relative size
  • Texture gradient
  • Aerial perspective
  • Light and shadow
  • Accommodation
  • Motion parallax
• Interpretation


  Influenced by:
• Subliminal stimuli


  Stimuli presented below the threshold of awareness