AP Psych U4

• Some people can see perfectly, but cannot recognize members of their family. This person has what's called prosopagnosia, AKA "face blindness." This illustrates the difference between sensation and perception.
• Sensation

  The ability to see, hear, touch, taste, and smell
• Perception

  How we put the impulses received from our senses together so they make sense
• Sensation is part of bottom-up processing where our senses send information to our brain. Perception is part of top-down processing where our brain assembles the info to make sense of the impulses being sent to it.
• Selective attention

  The ability to screen out sensory information and focus on only a small portion of it
• Selective attention

  • A housewife telling her husband the things that need to be done around the house while he's watching a football game on TV oblivious to what's she's saying
  • A person in a crowded, talking room can weed out other voices and converse with one person, then "tune in" on another person
• People that talk or text on the phone while driving are much more likely to crash (4 times more for talking, 23 times more for texting) because they selectively put their attention on one task at a time, driving or texting, and the other suffers.
• Selective inattention/Inattentional blindness

  The ability to purposefully block out all but one bit of sensory input - to focus on one thing only
• Selective inattention/Inattentional blindness

  • A person in a gorilla suit walked among people passing a basketball, but most people never saw the gorilla because they were focused on counting the basketball passes
  • People won't notice a change in "scenery" after a brief interruption
• Choice blindness


  People are unaware of the choices or preferences they make
• Choice blindness


  • Women were shown two pictures and asked to choose the most attractive person, then were tricked and shown the one they'd rejected and asked why they chose that person. Only 13% caught the switcheroo.
• Pop-out


  Something is noticeably different from the others and thus, pops out to the viewer
• Absolute threshold


  The minimum stimulation needed to detect light, a sound, a pressure, taste or odor 50% of the time
• People lose the ability to hear high-pitched sounds as they grow older. Teens use this to set "mosquito" ringtones that adults likely won't hear. Businesses use this to shoo away loitering teens.
• Signal detection theory


  The idea that predicting whether or not we detect a stimulus depends not only on the stimulus, but also on our experience, expectations, motivation, and alertness
• Subliminal stimulation/Subliminal perception


  Stimulation just below our level of consciousness, where we're subjected to a stimulus but we just aren't aware of it
• Subliminal stimulation


  Stimulation just below our level of consciousness. This occurs when we're subjected to a stimulus, but we just aren't aware of it.
• By definition, we can sense subliminal stimuli 49% of the time
• We're not sure if unconscious subliminal stimuli can impact our behavior
• Difference threshold


  The minimum difference between two stimuli that can be detected at least 50% of the time
• Weber's Law


  The difference between two stimuli must differ by a constant proportion, not necessarily a constant amount
• Sensory adaptation


  A person's diminishing sensitivity to a sensory stimulus. If a stimulus persists, you get used to it.
• Transduction


  The process where our eyes sense light energy and change it into neural messages that our brain can handle
• Visible light makes up a very small portion of the electromagnetic spectrum
• Frequency


  Refers to the wavelength of the light wave, or how frequently they hit
• Amplitude


  Refers to the intensity of the light wave, or how strongly they hit
• Vision


  1. Gathering light

  2. Within the eye

  3. Transduction

  4. In the Brain
• Cornea


  • Transparent protective coating over the front part of the eye
• Pupil


  • Small opening in the iris through which light enters the eye
• Iris


  • Colored part of the eye
• Lens


  • Transparent part of the eye inside the pupil that focuses light onto the retina
• Retina


  • Lining of the eye containing receptor cells that are sensitive to light. Transduction occurs here.
• Receptor cell


  • Specialized cell that responds to a particular type of energy
• Rods


  • Receptor cells in the retina responsible for night vision and perception of brightness
• Cones


  • Receptor cells in the retina responsible for color vision
• Fovea


  • Area of the retina that is the center of the visual field
• Optic nerve


  • Bundle of axons of ganglion cells that carries neural messages from each eye to the brain
• Blind spot


  • Place on the retina where the axons of all the ganglion cells leave the eye and where there are no receptors
• Optic chiasm


  • Point near the base of the brain where some fibers in the optic nerve from each eye cross to the other side of the brain
• Feature detectors


  Specialized cells in the brain that detect features like angles, lines, edges, and movements