Dikran J. Martin Psychology 110 Name: Date: Lecture Series: Chapter 3 Sensation and Perception: Pages: 31 Making Contact with the World around Us TEXT: Baron, Robert A. (2001). Psychology (Fifth Edition). Boston, MA: Allyn and Bacon. Introduction Principal Features "The study of sensation is concerned with the initial contact between organisms and their physical environment." "It focuses on describing the relationship between various forms of sensory stimulation (including electromagnetic, sound waves, pressure) and how these inputs are registered by our sense organs (the eyes, ears, nose, tongue, and skin)." "In contrast, the study of perception is concerned with identifying the processes through which we interpret and organize this information to produce our conscious experience of objects and relationships among objects." Sensation: The Raw Materials of Understanding What's the role of highly specialized cells known as sensory (85) receptors? -1-
Sensation: The Raw Materials of Understanding (Continued) What's the meaning of the following statement? " sights, sounds, and smells that we experience (85) are actually the product of transduction " Sensory Thresholds: How Much Stimulation Is Enough? What is sensory deprivation? (86) What is homeostasis insofar as sensory stimulation is (87) concerned? -2-
Sensory Thresholds: How Much Stimulation Is Enough? (Continued) What is absolute threshold insofar as sensory stimulation (87) is concerned? Research Methods How Psychologists Measure Sensory Thresholds The Role of Psychophysical Procedures What are psychophysical methods? [Example] Psychophysical methods. -3-
Research Methods How Psychologists Measure Sensory Thresholds The Role of Psychophysical Procedures (Continued) The Method of Limits [Example] Method of limits. (87) The Staircase Method [Example] The staircase method. The Method of Constant Stimuli [Example] The method of constant stimuli. (87-88) -4-
SENSORY THRESHOLDS: SOME COMPLICATIONS What is signal detection theory? (88) [Example] Signal detection theory. DIFFERENCE THRESHOLDS: ARE TWO STIMULI THE SAME OR DIFFERENT? What is the difference threshold? (89) [Example] Difference threshold (just noticeable difference - jnd). -5-
STIMULI BELOW THRESHOLD: CAN THEY HAVE AN EFFECT? What is the subliminal perception? (89) [Examples] Subliminal perception. (89-90) Sensory Thresholds: It Feels Great Once You Get Used to It What is the sensory adaptation? (91) -6-
Sensory Thresholds: It Feels Great Once You Get Used to It (Continued) [Example] Sensory adaptation. (91) Vision The Eye: Its Basic Structure How is light energy converted into signals our brain can (91-93) understand? Note the following: Cornea Pupil -7-
The Eye: Its Basic Structure (Continued) Note the following: Lens (93) Retina Cones Rods Fovea Optic nerve Blind spot Light: The Physical Stimulus for Vision Complete the following: " light that is visible to us is only a -8-
Light: The Physical Stimulus for Vision (Continued) Note the following: Wavelength (93) Hue Brightness Saturation Basic Functions of the Visual System: Acuity, Dark Adaptation, and Eye Movements What is the basic function of the visual system known as acuity? [Example] Acuity. (94) -9-
Basic Functions of the Visual System: Acuity, Dark Adaptation, and Eye Movements (Continued) What's the visual acuity differences between nearsightedness (94-95) and farsightedness? What is the basic function of the visual system known as dark adaptation? What is the basic function of the visual system known (95-96) as saccadic movements? -10-
Color Vision What is the trichromatic theory of color vision? (96) What are negative afterimages and why do they pose a problem for the trichromatic theory of color vision? What is the opponent-process theory of color vision? (96-97) Vision and the Brain: Processing Visual Information " the brain 'invents' our visual world." "The visual world we perceive results from a complex division of labor that only begins in the retina." -11-
Vision and the Brain: Processing Visual Information (Continued) What are feature detectors? (97) Complete the following: "One group of neurons, known as simple cells, respond to "A second group, complex cells, respond maximally to "Finally, hypercomplex cells respond to even more What's the meaning of the following statement? "These findings led scientists to the intriguing possibility that the brain processes visual hierarchically." -12-
Vision and the Brain: Processing Visual Information (Continued) What is blindsight? (98) What is prosopagnosia? Complete the following: "Taken together, these findings have important implications for our understanding of visual perception." "First they suggest that the visual system is quite "Second, because nature is rarely wasteful, the existence of cells specially equipped to detect certain features in the external world suggest that these features may be the "Finally, as illustrated by disorders such as blindsight and prosopagnosia, 'seeing' the world is a complex process one that requires precise integration -13-
Hearing The Ear: Its Basic Structure Note the following: Pinna (98-99) Eardrum (99) Middle ear Oval window Cochlea Hair cells Auditory nerve -14-
Sound: the Physical Stimulus for Hearing "Sound waves consist of alternating compressions of the air, or, more precisely, of the molecules that compose air." Complete the following: "The greater the amplitude (magnitude) of these waves, the (99) greater their What is the frequency of a sound wave? What is the pitch of a sound wave? What is the timbre of a sound wave? (100) Pitch Perception What is the place theory (traveling wave theory) of sound? (100-101) -15-
Pitch Perception (Continued) What is the frequency theory of sound? (101) Sound Localization What is the localization of sound? Premature Hearing Loss: The High Cost of Modern Living Complete the following: "Three types of hearing loss are usually distinguished:" "Temporary threshold shift (TTS), a short-term and reversible (102) "Permanent threshold shift (PTS), "Acoustic trauma, -16-
Premature Hearing Loss: The High Cost of Modern Living (Continued) [Examples] Decibels in everyday life. (103) Touch and Other Skin Senses What's the meaning of the following statement? "The skin is our largest sensory organ and (104) produces the most varied experiences " Pain: Its Nature and Control What are the two types of pain that we experience? -17-
Pain: Its Nature and Control (Continued) PAIN PERCEPTION: THE ROLE OF PHYSIOLOGICAL MECHANISMS What is the gate-control theory of pain? (104-105) [Examples] Gate control theory of pain. (105) PAIN PERCEPTION AND CULTURE What seems to account for cultural differences in pain threshold? -18-
PAIN PERCEPTION: THE ROLE OF COGNITIVE PROCESSES Complete the following: "The extent to which we experience pain results from a dynamic (105) interplay between two factors: How do cognitive-behavioral procedures counteract the (106) effects of pain? Smell and Taste: The Chemical Senses "Both (smell and taste) respond to substances in solution dissolved in a fluid or gas, usually water or air." " in everyday life, smell and taste are interrelated." Smell and Taste: How They Operate "The stimulus for sensations of smell consists of molecules of various substances (odorants) contained in the air." "Such molecules enter the nasal passages, where they dissolve in moist (106-107) nasal tissues." "This brings them in contact with receptor cells contained in the (107) olfactory epithelium." -19-
Smell and Taste: How They Operate (Continued) What's the meaning of the following statement? "Our olfactory senses are restricted " (107) What is the stereochemical theory of smell? "The sensory receptors for taste are located inside small bumps on the tongue known as papillae." "Within each papilla is a cluster of taste buds." Complete the following: " there appear to be only four basic tastes: Why do people perceive many more tastes than the (107-108) basic four? -20-
Smell and Taste: Some Interesting Facts "Despite the relative lack of research effort, many interesting facts have been uncovered about smell and taste." [Evidence] Facts about smell and taste. (108-109) -21-
Kinesthesia and Vestibular Sense What is the kinesthesia sense? (109) [Examples] Kinesthetic sense. What is the vestibular sense? (110) [Examples] Vestibular sense. -22-
Perception: Putting It All Together Complete the following: " the process of perception (is) the way in which we (112) Perception: The Focus of Our Attention What's the meaning of the following statement? (112-113) " we selectively attend to certain aspects of our environment " Perception: Some Organizing Principles Who were the Gestalt psychologists? (113) -23-
FIGURE AND GROUIND: WHAT STANDS OUT? What is a figure-ground relationship principle of perceptual (113) organization? [Examples] Figure-ground relationship. (114) GROUPING: WHICH STIMULI GO TOGETHER? What are Gestalt laws of grouping? [Examples] Laws of perceptual grouping. (115) -24-
Constancies and Illusions: When Perception Succeeds and Fails "Perception is the active selection, organization, and interpretation of (sensory) input." PERCEPTUAL CONSTANCIES: STABILITY IN THE FACE OF CHANGE What are perceptual constancies? (114) What is size constancy? [Examples] Size constancy. (114-115) What factors seem to account for the perception of size constancy? -25-
PERCEPTUAL CONSTANCIES: STABILITY IN THE FACE OF CHANGE (Continued) What is shape constancy? (115) What is brightness constancy? (115-116) ILLUSIONS: WHEN PERCEPTION FAILS What are illusions? (116) [Example] Illusions. (117-118) -26-
ILLUSIONS: WHEN PERCEPTION FAILS What's the meaning of the following statement? (118) "Illusions are not limited to visual processes." Some Key Perceptual Processes: Pattern and Distance PATTERN RECOGNITION: WHAT'S OUT THERE? What's the difference between the bottom-up approach and (118-119) the top-down approach in terms of explaining perceptual processing skills? [Illustrations] Bottom-up and top-down perceptual processing skills. (119) -27-
DISTANCE PERCEPTION: HOW FAR AWAY IS IT? "Our impressive ability to judge depth and distance exists because we make use of many different cues in forming such judgments." Complete the following: "Monocular cues to depth or distance include the following:" 1. Size cues. (119) 2. Linear perspective. 3. Texture gradient. 4. Atmospheric perspective. (120) 5. Overlap. 6. Height cues (aerial perspective). 7. Motion parallax. "Binocular cues for depth perception stem from two primary sources:" 1. Convergence. 2. Retinal disparity (binocular parallax). -28-
The Plasticity of Perception: To What Extent Is It Innate or Learned Perception: Evidence That It's Innate [Evidence] Evidence that perception is innate. (121-122) Perception: Evidence That It's Learned [Evidence] Evidence that perception is learned. (122) -29-
Must We Resolve the Nature-Nurture Controversy? "Virtually all psychologists accept that both innate factors and experience are needed to provide a complete account of our perceptual abilities." [Illustrations] Integral roles of innate factors and experience in perception. (122) What's the meaning of the following statement? (122-123) " perception is plastic " Extrasensory Perception Perception without Sensation What is extrasensory perception? (123) -30-
Psi: What Is It? How do parapsychologists study psi and other paranormal (123) events? Psi: Does It Really Exist? Why are most psychologists skeptical about the existence (123-124) of psi? END -31-