Mod 3

• Sensation


  The activation of receptors in the various sense organs
• Sensory receptors


  • Specialized forms of neurons
  • Stimulated by different kinds of energy rather than by neurotransmitters
• Sense organs


  • eyes
  • ears
  • nose
  • skin
  • taste buds

  
• Transduction


  Turning outside stimuli into neural activity
• Just noticeable difference (jnd or the difference threshold)


  The smallest difference between 2 stimuli that is detectable 50 percent of the time
• Absolute threshold


  The smallest amount of energy needed for a person to consciously detect a stimulus 50 percent of the time it is present
• Subliminal stimuli


  • Stimuli that are below the level of conscious awareness
  • Just strong enough to activate the sensory receptors, but not strong enough for people to be consciously aware of them
• Subliminal perception


  The process by which subliminal stimuli act upon the unconscious mind, influencing behavior
• Sensation


  The activation of receptors in the various sense organs
• Sensory receptors


  Specialized forms of neurons stimulated by different kinds of energy rather than by neurotransmitters
• Sense organs


  • Eyes
  • Ears
  • Nose
  • Skin
  • Taste buds
• Transduction


  Turning outside stimuli into neural activity
• Just noticeable difference (jnd or the difference threshold)


  The smallest difference between 2 stimuli that is detectable 50 percent of the time
• Absolute threshold


  The smallest amount of energy needed for a person to consciously detect a stimulus 50 percent of the time it is present
• Subliminal stimuli


  Stimuli that are below the level of conscious awareness, just strong enough to activate the sensory receptors, but not strong enough for people to be consciously aware of them
• Sublimin


  Below the threshold
• Subliminal perception


  The process by which subliminal stimuli act upon the unconscious mind, influencing behavior
• Subliminal messages and perception are linked to the idea of mind control, and the roots of this are placed very far back in our history
• Mind control


  Where an individual or group of individuals can be controlled without their awareness, it is perception below the individual's/group's threshold, and the idea that people can be made to do things they would not ordinarily do
• Ways in which subliminal messages can be sent to the unconscious

  • Visual
  • Auditory
• Habituation


  The tendency of the brain to stop attending to constant, unchanging information
• Sensory adaptation


  The tendency of sensory receptor cells to become less responsive to a stimulus that is unchanging
• Brightness


  Determined by the amplitude of the wave - how high or how low the wave actually is
• Higher wave


  Brighter light
• Lower wave


  Dimmer light
• Color/Hue


  Determined by the length of the wave
• Long wavelengths are found at the red end of the visible spectrum
• Color/Hue


  Determined by the length of the wave
• Visible spectrum


  • Long wavelengths are found at the red end
  • Shorter wavelengths are found at the blue end
• Saturation


  The purity of the color people sees
• Mixing in black or gray

  Lessens the saturation
• Cornea


  • Clear membrane that covers the surface of the eye
  • Protects the eye
  • Focuses most of the light coming into the eye
• Aqueous humor


  • Clear, watery fluid that is continually replenished
  • Supplies nourishment to the eye
• Pupil


  • Hole through which light from the visual image enters the interior of the eye
• Iris


  • Round muscle (the colored part of the eye) in which the pupil is located
  • Can change the size of the pupil, letting more or less light into the eye
  • Helps focus the image
• Lens


  • Clear structure behind the iris, suspended by muscles
  • Finishes the focusing process begun by the cornea
• Visual accommodation


  The change in the thickness of the lens as the eye focuses on objects that are far away or close
• Vitreous humor


  Jelly-like fluid that also nourishes the eye and gives it shape
• Nearsightedness (myopia)


  • The shape of the eye causes the focal point to fall short of the retina
• Farsightedness (hyperopia)


  • The focus point is behind the retina