I. Sensation and perception chapter 6

Sensation [p186]  The detection of physical energy emitted or reflected by physical objects  Occurs when energy in the external environment or the body stimulates receptors in the sense organs (eyes, ears, nose, skin, tongue)  Sense receptors are specialized cells that convert physical energy into electrical energy that can be transmitted as nerve impulses to the brain chapter 6

Perception [p186] The process by which the brain organizes and interprets sensory information The process by which the brain organizes and interprets sensory information

II. Measuring the senses chapter 6

Psychophysics The study of the relationship between the physical characteristics of stimuli (such as their intensity) and our psychological experience of them [p187] How close does a candle flame have to be to see it? How close does a watch have to be to hear it? How much sugar to taste it? How much perfume to smell it? How much pressure to feel it? chapter 6

Absolute thresholds [pp ] The smallest quantity of physical energy that can be reliably detected by an observer (reliable=50% of the time) Vision A single candle flame from 30 miles on a clear night Hearing The tick of a watch from 20 feet in total quiet Smell One drop of perfume in a 6-room apartment Touch The wing of a bee on the cheek, dropped from 1 cm Taste One teaspoon of sugar in 2 gallons of water chapter 6

Noise A term given to competing and irrelevant stimuli chapter 6

Physical condition chapter 6

Sensory adaptation [p190] The reduction or disappearance of sensory responsiveness when stimulation is unchanging or repetitious chapter 6

Sensory deprivation [p190] The absence of normal levels of sensory stimulation chapter 6

Selective attention The focusing of attention on selected aspects of the environment and the blocking out of others [p190] “The cocktail party effect” chapter 6

The Stroop Effect Demonstrates 1. a failure of selective attention 2. a difficulty with ignoring or blocking out very familiar stimuli. chapter 6

III. Vision chapter 6

Light waves [p191] The physical energy needed to see. chapter 6

The eye [p192] Cornea Protects eye and bends light toward lens Lens Focuses on objects by changing shape (accommodation) Iris Controls amount of light that gets into eye Pupil Aperture through which light reaches the retina chapter 6

The eye [pp ] Retina Neural tissue lining the back of the eyeball’s interior containing the receptors for vision Rods Visual receptors that respond to dim light Cones Visual receptors involved in color vision chapter 6

Visual information processing The optic nerve carries neural impulses from the eye to the visual areas of the brain [p193] chapter 6

IV. Hearing chapter 6

Sound waves [p203] The physical energy needed to hear chapter 6

The ear [pp ] Outer ear: pinna and external auditory canal Outer ear: pinna and external auditory canal Middle ear: eardrum and middle ear bones Middle ear: eardrum and middle ear bones Inner ear: cochlea Inner ear: cochlea chapter 6

Auditory processing [p204] The auditory nerve carries neural impulses from the ear to the brain’s auditory areas. chapter 6

V. Touch chapter 6

Sensitivity to touch [p209] Pressure Pressure Temperature Temperature Pain warns us that damage to our bodies is occurring Pain warns us that damage to our bodies is occurring chapter 6

Gate-control theory of pain Experience of pain depends in part on whether the pain gets past a neurological “gate” in the spinal cord. [p209] chapter 6

Gate-control theory revised [p210] The matrix of neurons in the brain is capable of generating pain (and other sensations) in the absence of signals from sensory nerves. chapter 6

Neural processing of touch, temperature, pain information Occurs in somatosensory cortex of parietal lobes chapter 6

VI. Taste chapter 6

Taste [pp ] The detection of chemicals that have been dissolved in saliva. Each papilla contains about 200 taste buds. Each taste bud contains receptors. chapter 6

Five tastes [p206] Five basic tastes Salty, sour, bitter, sweet, umami Different people have different tastes based on: GeneticsCultureLearning Food attractiveness Information from the taste receptors is carried by cranial nerves to the parietal lobes. chapter 6

VII. Smell chapter 6

Smell [p207] Airborne chemical molecules enter the nose and circulate through the nasal cavity. Vapors can also enter through the mouth and pass into nasal cavity. Receptors on the roof of the nasal cavity detect these molecules and relay information to the frontal lobes. chapter 6

VIII. Body position and movement chapter 6

The environment within [pp ] Kinesthesis The sense of body position and movement of body parts Equilibrium The sense of balance Semicircular canals Sense organs in the inner ear, which contribute to equilibrium by responding to rotation of the head Neural processing Occurs in frontal and parietal lobes chapter 6

IX. Perceptual Organization chapter 6

Form perception [p197] Allows us to differentiate objects we see Gestalt=organized whole Gestalt principles describe the brain’s organization of sensory building blocks into meaningful units and patterns Figure-ground is the Gestalt principle by which we organize perceptual fields into forms that stand out (figure) and those that are left over (ground) chapter 6

Ambiguous figure-ground relationships

Gestalt principles [pp ] Proximity Things close to one another are grouped together Closure The brain tends to fill in gaps to perceive complete forms chapter 6

Gestalt principles Similarity Things that are alike are perceived together [p198] chapter 6

Depth perception [p199] Allows us to judge distance Binocular cues Visual cues that require the use of both eyes Retinal disparity The slight difference in what the right and left eyes see chapter 6

Monocular cues [p199] Visual cues that can be used by one eye Sometimes called pictorial cues chapter 6

Relative size [p199] When viewing 2 objects that are similar in size, the smaller image will be perceived as being farther away When viewing 2 objects that are similar in size, the smaller image will be perceived as being farther away

Linear perspective [p199] Parallel lines that converge indicate depth Parallel lines that converge indicate depth

Overlap (interposition) [p198] An object partially covering another object is perceived as closer An object partially covering another object is perceived as closer

Perceptual constancies [p200] The perception of objects as stable or unchanged despite changes in the sensory patterns they produce Shape constancy Location constancy Size constancy Brightness constancy Color constancy chapter 6

Visual illusions [pp ] Occur when two objects produce the same retinal image but are perceived as different images chapter 6

Psychological and cultural influences [pp ] We are more likely to perceive something when we need it. What we believe can affect what we perceive. Emotions, such as fear, can influence perceptions of sensory information. Expectations based on previous experiences can influence perception. All are influenced by culture. chapter 6