AP PSYCHOLOGY Review for the AP Exam Chapter 5-

1. AP PSYCHOLOGYReview for the AP ExamChapter 5-

2. SENSATION Chapter 5

3. Sensation *a process by which our sensory receptors and nervous system receive and represent stimulus energy Perception *a process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events Bottom-Up Processing *analysis that begins with the sense receptors and works up to the brain’s integration of sensory information Top-Down Processing *information processing guided by higher-level mental processes *as when we construct perceptions drawing on our experience and expectations The implications of this top to bottom flow if information is that information coming into the system (perceptually) can be influenced by what the individual already knows about the information that is coming into the system

4. Sensation- Basic Principles Psychophysics *study of the relationship between physical characteristics of stimuli and our psychological experience of them *Light- brightness *Sound- volume *Pressure- weight *Taste- sweetness TRANSDUCTION:transformation of one form of energy into another-- especially the transformation of stimulus information into nerve signals by the sense organs. Without transduction, ripe tomatoes would not appear red (or pinkish gray--in the case of many tomatoes purchased in the grocery store).

5. SENSORY ADAPTATION--loss of responsiveness in receptor cells after stimulation has remained unchanged for a while, as when a swimmer becomes adapted to the temperature of the water. Absolute Threshold *minimum stimulation needed to detect a particular stimulus *usually defined as the stimulus needed for detection 50% of the time Difference Threshold *minimum difference between two stimuli that a subject can detect 50% of the time *just noticeable difference (JND) *increases with magnitude

6. Sensation- Thresholds Signal Detection Theory *predicts how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise) *assumes that there is no single absolute threshold *detection depends partly on person’s • experience • expectations • motivation • level of fatigue Weber’s Law- to perceive a difference between two stimuli, they must differ by a constant proportion • light intensity- 8% • weight- 2% • tone frequency- 0.3%

7. Vision- Stabilized Images on the Retina Our perceptions are organized by the meanings our minds impose. Transduction- conversion of one form of energy to another Wavelength- the distance from the peak of one wave to the peak of the next Hue- dimension of color determined by wavelength of light Intensity- amount of energy in a wave determined by amplitude • brightness • loudness

8. Vision- Spectrum of Electromagnetic Energy

9. Great amplitude (bright colors, loud sounds) Short wavelength=high frequency (bluish colors, high-pitched sounds) Long wavelength=low frequency (reddish colors, low-pitched sounds) Small amplitude (dull colors, soft sounds) Vision- Physical Properties of Waves Amplitude: greatness of magnitude….(physics) the maximum displacement of a periodic wave Wave amplitude determines the intensity of colors and sounds.

10. Vision Pupil-adjustable opening in the center of the eye Iris- a ring of muscle that forms the colored portion of the eye around the pupil and controls the size of the pupil opening Lens-transparent structure behind pupil that changes shape to focus images on the retina

11. Vision Accommodation--the process by which the eye’s lens changes shape to help focus near or far objects on the retina • change in shape of lens • focus near objects Retina --the light-sensitive inner surface of the eye, containing receptor rods and cones plus layers of neurons that begin the processing of visual information • inner surface of eye • light sensitive • contains rods and cones • layers of neurons • beginning of visual information processing

12. Retina’s Reaction to Light- Receptors Optic nerve- nerve that carries neural impulses from the eye to the brain Blind Spot- point at which the optic nerve leaves the eye, creating a “blind spot” because there are no receptor cells located there Fovea- central point in the retina, around which the eye’s cones cluster

13. Retina’s Reaction to Light- Receptors **Rods are more sensitive to light than the cones which is why the world looks colorless at night. Cones • near center of retina (fovea) • fine detail and color vision • daylight or well-lit conditions Rods • peripheral retina • detect black, white and gray • twilight or low light **Nocturnal animals such as mice, toads, rats and bats have retinas made up almost entirely of rods.

14. Receptors in the Human Eye Cones Rods Number 6 million 120 million Location in retina Center Periphery Sensitivity in dim light Low High Color sensitive? Yes No Vision- Receptors

15. Vision Acuity- the sharpness of vision Nearsightedness--condition in which nearby objects are seen more clearly than distant objects because distant objects in front of retina • nearby objects seen more clearly • lens focuses image of distant objects in front of retina Farsightedness --condition in which faraway objects are seen more clearly than near objects because the image of near objects is focused behind retina • faraway objects seen more clearly • lens focuses near objects behind retina

16. Vision Farsighted Nearsighted Normal Vision Vision Vision Light rays from distant objects focus in front…when image reaches the back, the rays spread out creating a blur. Light rays from near objects focus behind the retina creating a blur.

17. Cell’s responses Stimulus Visual Information Processing Feature Detectors • neurons in the visual cortex respond to specific features • shape • angle • movement Illusory Contours Subjective Contours

18. Visual Information Processing Parallel Processing • simultaneous processing of several dimensions through multiple pathways (color, motion, form, depth) Trichromatic (three color) Theory • Young (1802) and Helmholtz (1850) • three different retinal color receptors • red • green • blue You see colors according to their response to the wavelengths of light striking the retina---short-preferring (blue), middle-preferring (green), and long-preferring (red).

19. Visual Information Processing Opponent-Process Theory- opposing retinal processes enable color vision “ON” “OFF” red green green red blueyellow yellow blue black white white black

20. Visual Information Processing Color Constancy Perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object

21. Audition Audition • the sense of hearing Frequency • the number of complete wavelengths that pass a point in a given time Pitch • a tone’s highness or lowness • depends on frequency

22. Audition- The Ear Outer Ear • Auditory Canal • Eardrum Middle Ear--chamber between eardrum and cochlea containing three tiny bones (hammer, anvil, stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window Inner Ear--innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs • oval window • Cochlea-- coiled, bony, fluid-filled tube in the inner ear • basilar membrane • hair cells

23. Audition Place Theory • the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated Frequency Theory • the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch How We Locate Sounds

25. Amplitude required for perception relative to 20-29 year-old group 1 time 10 times 100 times 1000 times 32 64 128 256 512 1024 2048 4096 8192 16384 Frequency of tone in waves per second Low Pitch High Conduction Hearing Loss • hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea Nerve Hearing Loss • hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerve Older people tend to hear low frequencies well but suffer hearing loss for high frequencies 20-29 years 30-39 years 40-49 years 50-59 years Over 60 years

26. Touch Skin Sensations • pressure • only skin sensation with identifiable receptors • warmth • cold • pain

27. Pain Gate-Control Theory • theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain • “gate” opened by the activity of pain signals traveling up small nerve fibers • “gate” closed by activity in larger fibers or by information coming from the brain Sometimes a child can be afflicted with a disorder known as CIPA -- congenital insensitivity to pain with anhidrosis, She can feel touch, her brain doesn't receive signals that she's experiencing pain, and she hardly sweats. When Gabby was 4 months old, she was biting her fingers until they bled. By the time she was 2, her teeth had to be removed so she wouldn't hurt herself. When she was a toddler, Gabby scratched her cornea and was given eye gel, The thick gel had a reflux reaction to rub your eye, Because one eye became so infected, it had to be removed

28. Taste Taste Sensations • sweet • sour • salty • bitter Sensory Interaction • the principle that one sense may influence another • as when the smell of food influences its taste

29. Number of correct answers Women and young adults have best sense of smell 4 Women 3 Men 2 0 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99 Age Group Age, Sex and Sense of Smell

30. Body Position and Movement Kinesthesis • the system for sensing the position and movement of individual body parts Vestibular Sense • the sense of body movement and position • including the sense of balance

31. PERCEPTION Chapter 6

32. Perception ….means that at any moment we focus our awareness on only a limited aspect of all that we are capable of experiencing. Selective Attentionfocus of conscious awareness on a particular stimulus Change Blindness

33. Perceptual Illusions

34. Perceptual Illusions

35. Perceptual Illusions

36. Perceptual Illusions

37. Picture or a word?

38. Perceptual Organization- Gestalt Visual Capture • tendency for vision to dominate the other senses Gestalt--an organized whole • tendency to integrate pieces of information into meaningful wholes Escher

39. Perceptual Organization- Gestalt Grouping • the perceptual tendency to organize stimuli into coherent groups Grouping Principles • proximity- group nearby figures together • similarity- group figures that are similar • continuity- perceive continuous patterns • closure- fill in gaps • connectedness- spots, lines and areas are seen as unit when connected ___ ___ ___ - ___ ___ - ___ ___ ___ ___ ___ ___ ___ - ___ ___ ___ - ___ ___ ___ ___ ___ ___ ___ ___ ___ - ___ ___ ___ ___

40. Perceptual Organization- Grouping Principles

41. Closure Illusory Contours

42. Perceptual Organization • Figure and Ground--organization of the visual field into objects (figures) that stand out from their surroundings (ground)

43. Perceptual Organization- Grouping Principles Gestalt grouping principles are at work here.

44. Perceptual Organization-Depth Perception Depth Perception • ability to see objects in three dimensions • allows us to judge distance Binocular cues • retinal disparity • images from the two eyes differ • closer the object, the larger the disparity • convergence • neuromuscular cue • two eyes move inward for near objects Visual Cliff

45. Perceptual Organization-Depth Perception Monocular Cues • relative size ** • smaller image is more distant • interposition • closer object blocks distant object • relative clarity • hazy object seen as more distant • texture coarse --> close fine --> distant • relative height ** • higher objects seen as more distant • relative motion • closer objects seem to move faster • linear perspective • parallel lines converge with distance • relative brightness • closer objects appear brighter

46. Interposition Light & Shadow

47. Perceptual Organization-Depth Perception Perspective Techniques

48. Perceptual Organization: Depth Perception Illusory Depth Photographer Walter Wick cut out pieces of paper shaped to imitate stair positions and colored them to simulate light and shadow.

49. Perceptual Constancy Perceptual Constancy perceiving objects as unchanging despite changes in retinal image • color • shape • size Ponzo Illusion

50. Perceptual Organization-Muller-Lyer Illusion