Sensation & Perception

Question 1

What is the difference between sensation and perception?

Answer 1

Sensation is the process of gathering sensory information about the environment and transmitting it to the brain; perception is the process of organising and interpreting the sensations

Question 2

How does sensation begin?

Answer 2

With a detectable stimulus

Question 3

What is the absolute threshold?

Answer 3

The minimum stimulus intensity required for detection (detected 50% of the time)

Question 4

What is the signal-detection theory?

Answer 4

Sensation = Sensory processes + decision processes

Question 5

What is the difference threshold?

Answer 5

The lowest level of stimulation required to sense that a change in stimulation has occurred (a just noticeable difference)

Question 6

Are sensation and perception passive or active processes?

Answer 6

Active

Question 7

What is the evolutionary perspective of sensory and perceptual processes?

Answer 7

They reflect the impact of adaptive pressures

Question 8

What are the five common features of the senses?

Answer 8

1) They must translate physical stimuli into sensory signals
2) They have thresholds
3) Sensation requires constant decision-making
4) Ability to detect changes in stimuli
5) Ability to tune out stimuli that continue without change

Question 9

What is transduction?

Answer 9

The process of converting physical energy or stimulus information into neural impulses

Question 10

For what two features does the brain code sensory stimulation?

Answer 10

Intensity and quality

Question 11

What are the three laws regarding difference thresholds?

Answer 11

Weber’s, Fechner’s and Stevens’ power laws

Question 12

What is adaptation?

Answer 12

Sensory receptors respond less to stimuli with repeated exposure

Question 13

When do feature detectors in the primary visual cortex respond?

Answer 13

When stimulation in their receptive field matches a particular pattern or orientation

Question 14

What do the ventral and dorsal visual pathways process?

Answer 14

Ventral: Form & colour
Dorsal: Depth & motion

Question 15

What is the trichromatic theory?

Answer 15

The eye has 3 receptors for red, green and blue

Question 16

What is the opponent-process theory?

Answer 16

There are three antagonistic colour systems: blue/yellow, red/green and black/white

Question 17

What is the stimulus for hearing?

Answer 17

Sound waves

Question 18

What is sound wave frequency experienced as?

Answer 18

Pitch

Question 19

What is the place theory of hearing?

Answer 19

Perception of pitch corresponds with different places along the basilar membrane

Question 20

What is the frequency theory of hearing?

Answer 20

Perception of pitch corresponds to the frequency at which the entire membrane vibrates

Question 21

What is the travelling-wave theory of hearing?

Answer 21

The whole membrane moves, but waves peak at different places

Question 22

What two cues are critical for auditory localisation?

Answer 22

Intensity (loudness) and timing of the sounds arriving at each ear

Question 23

What is the pathway for smell?

Answer 23

Olfactory cilia - neural impulse - olfactory nerve - olfactory bulb

Question 24

What is the gate control theory of pain?

Answer 24

Incoming pain sensation pass through a gate in the spinal cord that can be closed to block pain signals

Question 25

What is kinaesthesia?

Answer 25

Knowing the position of the various parts of the body

Question 26

What is form perception?

Answer 26

The organisation of sensations into meaningful shapes and patterns

Question 27

What are the four aspects of perceptual organisation?

Answer 27

Form perception, depth/distance perception, motion perception & perceptual constancy

Question 28

What are the Gestalt principles of form perception?

Answer 28

Pragnanz/simplicity, similarity, good continuation, proximity and closure

Question 29

What is the recognition-by-components theory?

Answer 29

People perceive and categorise objects by first breaking them down into elementary units

Question 30

What are perceptual illusions?

Answer 30

Perceptual misinterpretations produced by normal perceptual processes

Question 31

What is the law of pragnanz?

Answer 31

Also known as the law of good figure and law of simplicity; every stimulus is organised to be perceived in the simplest form possible (e.g. heart with arrow)

Question 32

What is the law of similarity?

Answer 32

Similar things are grouped together

Question 33

What is the law of good continuation?

Answer 33

The brain organises things into continuous lines or patterns

Question 34

What is the law of proximity?

Answer 34

Things that are near each other appear to be grouped together

Question 35

What is the law of closure?

Answer 35

Whenever possible, people see incomplete figures as complete

Question 36

What is depth/distance perception?

Answer 36

The organisation of perception in three dimensions

Question 37

What are binocular cues?

Answer 37

Cues from both eyes together

Question 38

What are two types of binocular cues?

Answer 38

Retinal disparity (e.g. colourblind chart) and convergence

Question 39

What are monocular cues?

Answer 39

Cues from a single eye

Question 40

What are three types of monocular cues?

Answer 40

Linear perspective (e.g. train tracks), texture gradient (e.g. blurring) and shading

Question 41

What does motion perception rely on?

Answer 41

Motion detectors from the retina through the cortex

Question 42

What is perceptual constancy?

Answer 42

The organisation of changing sensations into percepts that are relatively stable

Question 43

What are the three types of perceptual constancy?

Answer 43

Colour, shape and size constancy

Question 44

What is bottom-up processing?

Answer 44

Processing that begins with raw, sensory data that feed up to the brain

Question 45

What is top-down processing?

Answer 45

Begins with the observer's expectations and knowledge