Post on 13-Dec-2015
Essentials of Essentials of Understanding PsychologyUnderstanding Psychology
9th Edition
By Robert Feldman
PowerPoints by Kimberly Foreman
Revised for 9th Ed by Cathleen Hunt
Copyright McGraw-Hill, Inc. 2011
1
Chapter 3:Chapter 3:Sensation and PerceptionSensation and Perception
Copyright McGraw-Hill, Inc. 2011
2
MODULE 8: Sensing the World Around Us
• What is sensation, and how do psychologists study it?
• What is the relationship between a physical stimulus and the kinds of sensory responses that result from it?
Copyright McGraw-Hill, Inc. 2011
3
MODULE 8:Sensing the World Around Us
• Sensation– Activation of the sense organs by a source of physical energy
• Perception– Sorting out, interpretation, analysis, and integration of stimuli
carried out by the sense organs and brain
Copyright McGraw-Hill, Inc. 2011
4
MODULE 8:Sensing the World Around Us
• Stimulus– Any passing source of physical energy that produces a response
in a sense organ
• Psychophysics– Study of the relationship between the physical aspects of
stimuli and our psychological experience of them
Copyright McGraw-Hill, Inc. 2011
5
Absolute Thresholds: Detecting What’s Out There
• Absolute Threshold– Smallest intensity of a stimulus that must be present for it to be
detected
Copyright McGraw-Hill, Inc. 2011
6
Difference Thresholds: Noticing Distinctions Between Stimuli
• Difference Threshold– Smallest level of added (or reduced) stimulation required to
sense that a change in stimulation has occurred • Just noticeable difference
• Weber’s law
– Just noticeable difference is a constant proportion of the intensity of an initial stimulus
Copyright McGraw-Hill, Inc. 2011
7
Sensory Adaptation:Turning Down Our Responses
• Adaptation– An adjustment in sensory capacity after prolonged exposure to
unchanging stimuli
Copyright McGraw-Hill, Inc. 2011
8
MODULE 9: Vision: Shedding Light on the Eye
• What basic processes underlie the sense of vision?
• How do we see colors?
Copyright McGraw-Hill, Inc. 2011
9
Illuminating the Structure of the Eye
• Cornea– Protects eye and refracts light
• Pupil– Opening depends on amount of light in environment
• Iris– Colored part of eye
• Lens– Accommodation
Copyright McGraw-Hill, Inc. 2011
11
Illuminating the Structure of the Eye
• Reaching the Retina– Light is converted to electrical impulses for transmission to the
brain• Rods
– Receptor cells sensitive to light
• Cones
– Cone-shaped; responsible for sharp focus and color perception
– Concentrated in the fovea
Copyright McGraw-Hill, Inc. 2011
12
Illuminating the Structure of the Eye
• Sending the Message from the Eye to the Brain– Optic nerve
• Ganglion cells
• Blind spot
• Optic chiasm
Copyright McGraw-Hill, Inc. 2011
13
Illuminating the Structure of the Eye
• Processing the Visual Message– Takes place in the visual cortex of the brain
• Feature detection
Copyright McGraw-Hill, Inc. 2011
14
Color Vision and Color Blindness:The Seven-Million-Color Spectrum
• Explaining Color Vision– Trichromatic theory of color vision
• Suggests that there are three kinds of cones in the retina
– Blue-violet colors
– Green colors
– Yellow-red colors
» Not successful at explaining afterimages
Copyright McGraw-Hill, Inc. 2011
15
Color Vision and Color Blindness:The Seven-Million-Color Spectrum
• Opponent-process theory of color vision– Receptor cells are linked in pairs, working in opposition to each
other• Blue-yellow
• Red-green
• Black-white
– Explains afterimages
Copyright McGraw-Hill, Inc. 2011
16
MODULE 10: Hearing and the Other Senses
• What role does the ear play in the senses of sound, motion, and balance?
• How do smell and taste function?
• What are the skin senses, and how do they relate to the experience of pain?
Copyright McGraw-Hill, Inc. 2011
17
Sensing Sound
• Sound– Movement of air molecules brought about by a source of
vibration
• Eardrum– Vibrates when sound waves hit it
– Middle ear• Hammer, anvil, stirrup
Copyright McGraw-Hill, Inc. 2011
19
Sensing Sound
• Inner Ear– Changes sound vibrations into a form in which they can be
transmitted to the brain• Cochlea
– Filled with fluid and vibrates in response to sound
• Basilar membrane
– Dividing cochlea into an upper chamber and lower chamber
– Covered with hair cells
Copyright McGraw-Hill, Inc. 2011
20
Sensing Sound
• The Physical Aspects of Sound– Frequency
• Number of wave cycles that occur in a second
– Pitch
– Amplitude• Spread between the up-and-down peaks and valleys of air pressure in a
sound wave as it travels through the air
– Decibels
Copyright McGraw-Hill, Inc. 2011
21
Sensing Sound
• Sorting Out Theories of Sound– Place Theory of Hearing
• States that different areas of the basilar membrane respond to different frequencies
– Frequency Theory of Hearing• Suggests that the entire basilar membrane acts like a microphone,
vibrating as a whole in response to a sound
Copyright McGraw-Hill, Inc. 2011
22
Sensing SoundBalance: The Ups and Downs of Life
• Vestibular System– Semicircular canals
• Main structure of vestibular system
• Three tubes containing fluid that sloshes through them when the head moves, signaling rotational or angular movement to the brain
– Otoliths• Sense forward, backward, or up-and-down motion, as well as the pull of
gravity
Copyright McGraw-Hill, Inc. 2011
23
Smell
• Olfaction – Sense of smell is sparked when the molecules of a substance
enter the nasal passages • Olfactory cells
– Pheromones
Copyright McGraw-Hill, Inc. 2011
24
Taste
• Gustation– Taste qualities
• Sweet
• Sour
• Salty
• Bitter
• “Umami”
– Taste Buds• Supertasters
• Nontasters
Copyright McGraw-Hill, Inc. 2011
25
The Skin Senses:Touch, Pressure, Temperature, and Pain
• Substance P
• Gate-control Theory of Pain– Particular nerve receptors in the spinal cord lead to specific
areas of the brain related to pain • Acupuncture
Copyright McGraw-Hill, Inc. 2011
26
Managing Pain
• Medication• Nerve and brain stimulation• Light therapy• Hypnosis• Biofeedback and relaxation techniques• Surgery• Cognitive restructuring
Copyright McGraw-Hill, Inc. 2011
27
How Our Senses Interact
• Synesthesia• Multimodal perception
– Brain collects the information from the individual sensory systems and integrates and coordinates it
Copyright McGraw-Hill, Inc. 2011
28
MODULE 11: Perceptual Organization: Constructing Our View of the World
• What principles underlie our organization of the visual world and allow us to make sense of our environment?
• How are we able to perceive the world in three dimensions when our retinas are capable of sensing only two-dimensional images?
Copyright McGraw-Hill, Inc. 2011
29
MODULE 11: Perceptual Organization: Constructing Our View of the World
• What clues do visual illusions give us about our understanding of general perceptual mechanisms?
Copyright McGraw-Hill, Inc. 2011
30
The Gestalt Laws of Organization
• Series of principles that focus on the ways we organize bits and pieces of information into meaningful wholes– gestalts
Copyright McGraw-Hill, Inc. 2011
32
Top-Down and Bottom-Up Processing
• Top-Down Processing– Perception is guided by higher-level knowledge, experience,
expectations, and motivations
• Bottom-Up Processing– Consists of the progression of recognizing and processing
information from individual components of a stimulus and moving to the perception of the whole
Copyright McGraw-Hill, Inc. 2011
33
Depth Perception
• Ability to view the world in three dimensions and to perceive distance– Largely due to the fact that we have two eyes
• Binocular disparity
• Monocular cues
– Motion parallax
– Relative size
– Texture gradient
– Linear perspective
Copyright McGraw-Hill, Inc. 2011
35
Perceptual Constancy
• Phenomenon in which physical objects are perceived as unvarying and consistent despite changes in their appearance or in the physical environment
Copyright McGraw-Hill, Inc. 2011
36
Motion Perception:As the World Turns
• Cues about perception of motion– The movement of an object across the retina is typically
perceived relative to some stable, unmoving background
– Movement of images across the retina
– We factor in information about our own head and eye movements, along with information about changes in the retinal image
– Apparent movement
Copyright McGraw-Hill, Inc. 2011
37
Perceptual Illusions:The Deceptions of Perceptions
• Visual Illusions– Physical stimuli that consistently produce errors in perception
• Muller-Lyer illusion
Copyright McGraw-Hill, Inc. 2011
38
Culture and Perception
• Cultural differences are reflected in depth perception– Zulu vs. Westerner perspectives
Copyright McGraw-Hill, Inc. 2011
39
Subliminal Perception
• Perception of messages about which we have no awareness– Called priming
• Written word
• Sound
• Smell
Copyright McGraw-Hill, Inc. 2011
40
Extrasensory Perception (ESP)
• Perception that does not involve our known senses– Most psychologists reject the existence of ESP, asserting that
there is no sound documentation of the phenomenon
– Psychological Bulletin• “Anomalous process of information transfer” or psi
Copyright McGraw-Hill, Inc. 2011
41