Chapter 5: Sensation And Perception

Question 1

Sensation

Answer 1

Stimulus detection process by which our sense organs respond to and translate environmental stimuli into nerve impulses that are sent to the brain

Question 2

Perception

Answer 2

Making “sense” of what our senses tell us; it is the active process of organizing the stimulus and giving it meaning

Question 3

What is the difference between sensation and perception?

Answer 3

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Question 4

Sensory transduction

Answer 4

The process where the characteristics of a stimulus are converted into nerve impulses

Question 5

Psychophysics

Answer 5

Studies the relationship between the physical characteristics of stimuli and sensory capabilities (f.eks how low a sound can the human ear perceive)

Question 6

Absolute threshold

Answer 6

The lowest intensity at which a stimulus can be perceived by a human 50 percent of the time

Question 7

Decision criterion

Answer 7

A standard of how certain someone must be that a stimulus is present before they will say they can detect it

Question 8

Signal detection theory

Answer 8

Concerned with the factors that influence sensory judgements

Question 9

Difference threshold

Answer 9

Defined as the smallest difference between two stimuli that people can perceive 50 percent of the time

Question 10

Weber’s law

Answer 10

States that the difference threshold (or JND) is directly proportional to the magnitude of the stimulus with which the comparison is being made

Question 11

Sensory adaption

Answer 11

The diminishing sensitivity to an unchanging stimulus

Question 12

Lens (eye)

Answer 12

Elastic structure that becomes thinner to focus on distant objects, and thicker to focus on nearby objects

Question 13

Retina

Answer 13

Multilayered light-sensitive tissue at the rear of the fluid-filled eyeball

Question 14

Myopia

Answer 14

Nearsightedness

Question 15

Hyperopia

Answer 15

Farsightedness

Question 16

Rods (eye)

Answer 16

• primarily black and white brightness receptors

- function best in dim light

Question 17

Cones (eye)

Answer 17

• color receptors

- function best in bright illumination

Question 18

Fovea

Answer 18

Small area in the center of the retina that contains no rods, but mainly densely packed cones

Question 19

Optic nerve

Answer 19

Ganglion cells, whose axons are collected into a bundle to form the optic nerve

Question 20

Visual acuity

Answer 20

Ability to see fine detail

Question 21

Photo-pigments

Answer 21

Rods and cones translate light waves into nerve impulses through the action of protein molecules called photo-pigments

Question 22

Dark adaptation

Answer 22

The progressive improvement in brightness sensitivity that occurs over time under conditions of low illumination

Question 23

Young-Helmholtz trichromatic theory

Answer 23

States that there are three types of color receptor in the retina

Question 24

Hearing’s opponent-process theory

Answer 24

States that each of the three cone types responds to two different wavelengths

Question 25

Dual-process theory

Answer 25

Combines the trichromatic and opponent-process theory to account for the color transduction process

Question 26

Feature detectors (cells in retina)

Answer 26

Fire selectively in response to visual stimuli that has specific characteristics

Question 27

Two principal characteristics of sound waves

Answer 27

1: frequency (number of sound waves or cycles per second) hertz (Hz, the measure of cycles per second, 1Hz=1 cycles per sec) 2: amplitude (vertical size of the sound waves, depth between peaks and troughs) Decibels (dB, measure of the physical pressures that occur at the eardrum)

Question 28

Cochlea (ear)

Answer 28

Coiled, snail-shaped tube | Contains basilar membrane

Question 29

Basilar membrane

Answer 29

Sheet of tissue that runs the length of cochlea

Question 30

Organ of corti

Answer 30

Rests on basilar membrane | Contains thousands of tiny hair cells that are the actual sound receptors

Question 31

Frequency theory of pitch perception

Answer 31

Nerve impulses sent to the brain match the frequency of the sound wave

Question 32

Place theory of pitch perception

Answer 32

The specific point in the cochlea where the fluid wave peaks and most strongly bends the hair cells serves as a frequency coding cue

Question 33

Gustation

Answer 33

The sense of taste

Question 34

Olfaction

Answer 34

Sense of smell

Question 35

Taste buds

Answer 35

Small bodies containing taste receptor cells concentrated along the tip, edges and back surface of the tongue

Question 36

Olfactory system processing

Answer 36

Olfactory receptors that fire send their input to the olfactory bulb, which codes the signals in part via the area of the olfactory bulb which is excited = (Olfactory processing involves organizing olfactory neurons into groups representing the kinds of chemicals that have simulated them)

Question 37

Pheromones

Answer 37

Chemical signals found in natural body scents

Question 38

Orthonasal olfaction

Answer 38

Smelling something from outside your mouth

Question 39

Retronasal olfaction

Answer 39

Smelling something from the inside of your mouth (heavily involved with our perception of flavor)

Question 40

Cutaneous touch

Answer 40

The sense of touch arising from events on the skin surface (temperature and pressure)

Question 41

Proprioception

Answer 41

Sensory input that provides info on the layout and movements of our limbs

Question 42

Interoceptive touch

Answer 42

The sense of touch arising from receptors inside the body, usually blood vessels and organs

Question 43

Haptics

Answer 43

The active use of touch and movement to explore objects and surfaces within reach

Question 44

Sensory prosthetic devices

Answer 44

Provide sensory input that can, to some extent, substitute for what cannot be supplied by the persons sensory receptors

Question 45

Synaesthesia

Answer 45

Mixing of the senses

Question 46

Bottom-up processing

Answer 46

Individual elements of a stimulus are analysed and then combined to form a unified perception

Question 47

Top-down processing

Answer 47

Sensory information is interpreted in light of existing knowledge, concepts, ideas and expectations

Question 48

Figure-ground relations

Answer 48

Our tendency to organize stimuli into a central or foreground figure and a background

Question 49

Gestalt laws of perceptual organization

Answer 49

Similarity, proximity, closure and continuity

Question 50

Perceptual schema

Answer 50

A mental representation or image containing the critical and distinctive features of a person, object, event or other perceptual phenomenon

Question 51

Perceptual Constantine

Answer 51

Allow us to recognize familiar stimuli under varying conditions

Question 52

Monocular depth cues

Answer 52

Patterns of light and shadow, linear perspective, relative size

Question 53

Binocular depth cues

Answer 53

``` Binocular disparity (each eye sees a slightly different image) Convergence (produced by feedback from the muscles that move your eyes inward to view a close object) ```

Question 54

Stroboscopic movement

Answer 54

Illusory movement produced when a light is briefly flashed in darkness and then, a few milliseconds later, another light is flashed nearby

Question 55

Illusions

Answer 55

Compelling, yet incorrect perceptions

Question 56

Critical periods

Answer 56

Periods during which certain kinds of experiences must occur if perceptual abilities and the brain mechanisms that underlie them are to develop normally