PSY 201 Ch 4 Set B: Sensation Vision - Touch

  1. vision
    a system that converts light into neural activity; light is the stimulus, electromagnetic energy; most is invisible to human eye; visible light is a very small part of the electromagnetic spectrum
  2. properties of color
    hue, saturation, brightness
  3. hue
    color we see: blue, yellow, green, purple, etc.
  4. saturation
    dominance of hue, shades; how pure is the color; intensity or richness; decrease saturation looks more washed out
  5. brightness
    how strong is the color; varies based on strength of light entering eye; low brightness (dark/black), light brightness (light/white)
  6. the human eye
    cornea, aqueous humor, pupil, iris, lens
  7. cornea
    bends the light wave, protects the eye, contact lenses rest on it
  8. aqueous humor
    a watery substance in back of cornea; keeps rounded and glazy; nourishes the eye
  9. pupil
    an adjustable opening; constricts and dilates
  10. iris
    a translucent, doughnut-shaped muscle; controls size of pupil
  11. lens
    focus the visual image on the retina; one concave, one convex
  12. myopia
    nearsightedness; close objects are seen clearly; distance objects are blurry; image focuses in front of retina
  13. hyperopia
    farsightedness; distance objects are seen clearly; close objects are blurry; image is focused behind retina
  14. ciliary muscles
    changes the shape of the lens to bend light rays; ocular accommodation
  15. ocular accommodation
    close objects get rounder; far objects get less round
  16. vitreous humor
    jelly-like substance, most of eye; gives shape to eye
  17. retina
    a multilayered light-sensitive tissue; transduction occurs here; retinal image is upside down, flipped right-side up by brain; retinal focus may be improved with eyeglasses or contact lenses
  18. photoreceptors
    in retina, perform transduction; 2 types: rods and cones
  19. rods
    highly sensitive to light; function best in dim light; primarily black-and-white; not sensitive to color; located in periphery
  20. cones
    less sensitive to light; better in bright light; distinguishes colors; concentrated in fovea (center)
  21. bipolar neurons
    pass signals from photoreceptors to ganglion cells
  22. ganglion cells
    on surface of retina; generate action potentials; make up the optic nerve
  23. fovea
    a small area in the center of the retina; densely packed cones, contains no rods
  24. blindspot
    point at which optic nerve exits the eye; no receptor cells
  25. light adaptation
    increasing ability to see in the light as time in the light increases
  26. dark adaptation
    increasing ability to see in the dark as time in the dark increases; going into a movie theater
  27. Trichromatic Theory (of color vision)
    Young-Helmholtz; cones are most sensitive to wavelengths corresponding to blue, green, and red
  28. Three types of cones
    short-wavelength, medium-wavelength, and long-wavelength
  29. short-wavelength
    most sensitive to blue
  30. medium-wavelength
    most sensitive to green
  31. long-wavelength
    most sensitive to reddish-yellow
  32. limitations of the Trichromatic Theory
    cannot explain some aspects of color vision; after image: ex. red, white, blue flag after staring at dot
  33. Opponent-Process Theory (of color vision)
    color-sensitive visual elements are grouped into pairs; pair members oppose (inhibit) each other; red/green, blue/yellow, black/white; explains color afterimages
  34. Dual-Process Theory
    combines the two theories to account for color perception; trichromatic cones are most sensitive to blue, green, and red; opponent processes begin in ganglion cells and beyond
  35. colorblindness
    inability to sense certain colors
  36. trichromats
    people with normal color vision
  37. dichromat
    people who are color-blind in one of the three systems
  38. monochromat
    peple who are completely color-blind; sensitive only to the black-white system; extremely rare; more common in boys
  39. Chemical senses
    smell and taste; no animal is without some form of chemical sense
  40. olfactory perception
    our sense of smell; nose, mouth, and upper part of throat; detects airborne chemicals; does not connect through the thalamus; connects through the olfactory bulb in brain; receives messages regarding smell
  41. gustatory
    taste perception; mouth; detects chemicals in solutions that contact receptors in the mouth; about 10,000 taste buds in a person's mouth; grouped in a structure called papillae; most on the tongue
  42. human taste system detects
    only a few elementary sensations: sweet, sour, bitter, and salty
  43. flavor
    produced by an interaction between taste and smell; what makes food taste good are actually odors detected by the olfactory system; joins smell, taste, sight, texture, temperature, hunger, and satiety
  44. touch
    people can function without vision, hearing , or smell; trouble surviving without touch; energy detected by the sense of touch, physical pressure; skin has hairs all over it; transduction occurs in the receptors in or just below the skin
  45. encoding of touch information: the skin encodes the intensity of a stimulus by
    firing rate of individual neurons and the number of neurons stimulated
Author
nisab44
ID
268955
Card Set
PSY 201 Ch 4 Set B: Sensation Vision - Touch
Description
exam 3
Updated