Essentials of Understanding Psychology 9 th Edition By Robert Feldman BY:Azhar ali (RED ROSE N) 1.

Essentials of Essentials of Understanding PsychologyUnderstanding Psychology

9th Edition

By Robert Feldman

BY:Azhar ali (RED ROSE N)

1

Chapter 3:Chapter 3:Sensation and PerceptionSensation and Perception


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?


3

MODULE 8:Sensing the World Around Us

• Sensation– Activation of the sense organs by a source of physical energy

– For example light activate the eye for sight.

• Perception– Sorting out, interpretation(translate), analysis, and integration

of stimuli carried out by the sense organs and brain


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


5

Absolute Thresholds: Detecting What’s Out There

• Absolute Threshold– Smallest intensity of a stimulus that must be present for it to be

detected

– Our sensory organs are as sensitive that we can feel a small stimuli.

• Difference Threshold– Smallest level of added (or reduced) stimulation required to

sense that a change in stimulation has occurred


6

Sensory Adaptation:Turning Down Our Responses

• Adaptation– An adjustment in sensory capacity after prolonged exposure to

unchanging stimuli.

– The sense diminish when a stimuli become familiar with a sensory organ.


7

Basic Cells of the Eye


8

Illuminating the Structure of the Eye

• Cornea– Protects eye and refracts light

– It’s a transparent window.

• Pupil– It’s a dark hole in the center of the iris.

– Opening depends on amount of light in environment

• Iris– Colored part of eye & protect the internal parts of eye.

• Lens– It changes its position to focuses the light.


9


• 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


10


• Processing the Visual Message– Takes place in the visual cortex of the brain

• Feature detection


11

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


12

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


13

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?


14

The Ear


15

Sensing Sound

• Sound– Movement of air molecules brought about by a source of

vibration

• Eardrum– Vibrates when sound waves hit it

– Middle ear consists of three types of bones• Hammer, anvil, stirrup


16

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


17

Sensing Sound

• Sorting Out Theories of Sound– Place Theory of Hearing

• It 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


18

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• Small tiny crystals in semicircular canals which Sense forward,

backward, or up-and-down motion, as well as the pull of gravity


19

Smell

• Olfaction– Sense of smell is sparked when the molecules of a substance

enter the nasal passages • Olfactory cells: it secretes a chemical in which the odor diffuse in it and

produce an impulse.

– Pheromones : it is use in sexual activity in animals.

• There are more than 100 receptors are present in nasal cavity.


20

Taste

• Gustation– Taste qualities

• Sweet

• Sour

• Salty

• Bitter

• “Umami”

– Taste Buds• Supertasters: these are most sensitive to taste.

• Nontasters :these are less sensitive to taste.


21

How Our Senses Interact

• Synesthesia• Multimodal perception

– Brain collects the information from the individual sensory systems and integrates and coordinates it


22

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?


23

MODULE 11: Perceptual Organization: Constructing Our View of the World

• What clues do visual illusions give us about our understanding of general perceptual mechanisms?


24

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


25

Top-Down Processing


26

Perceptual Constancy

• Phenomenon in which physical objects are perceived as unvarying and consistent despite changes in their appearance or in the physical environment.

• For example when you leave your friend and look at them after few minutes he become smaller.


27

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


28

Subliminal Perception

• Perception of messages about which we have no awareness– Called priming

• Written word

• Sound

• Smell


29

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


30

Essentials of Understanding Psychology 9 th Edition By Robert Feldman BY:Azhar ali (RED ROSE N) 1.

Documents

Transcript of Essentials of Understanding Psychology 9 th Edition By Robert Feldman BY:Azhar ali (RED ROSE N) 1.