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Pyschology > Perception > Flashcards

Flashcards in Perception Deck (76)
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1
Q

3 aspects of perception

A
  • not hieriarchal
  • is the interpretation of sensations to make sense of environment
  • depends on contextual cuex
2
Q

colour constancy

A

how we percieve coour changes depending on illumination, contrast, etc

3
Q

depth perception

A

shape
concentrationg
shading
concavity

(HOW WE SEE 3D OBJECTS IN RETINAS 2D STATE)

4
Q

expectaions affect on perception

A

previous experience and knowledge of the world infleunces how we see things; especially in ambigious situations

5
Q

the brain and perception

A

integrates information from different sensory modalities to produce and interpret

6
Q

mcgurk effect

A

multi-sensory perception effect where ther eis a conflict between VISUAL and AUDITORY information

e.g. V vs D vs B mouth shape and sound

7
Q

ventriloquist effect

A

a multi-sensory perception effect where visual adn audodoration LOCALIZISATIOn conflicgts;
illusion of thinking sound comes from a dummy even though location of sound is from ventrioloquist

8
Q

Berman and Weich 1976 experiment

A

method= played a beep and a flash of light from differet locations and had participants point to where they think the sound came from

results= localization of sound dragged the light

9
Q

perception as inference

A

visual system crates accruate, detailed and 3D percpetp frion small, tiny 2d retinal images

10
Q

how to study perception

A
  1. how receptors carry electrical signals using action potentials (raw data)
  2. how our perspection is subjective and changes contextually (interpreation in the brain)
11
Q

what is sensation

A

raw data processed by sensory rerecptors sch as eyes, ears, nose, etc [bottom up]

12
Q

what is perception

A

how sensations are processsed and interpreted into the brain [top down]

13
Q

why do our eyes prefer visual over auditory information

A

because visual information is more precise than our ears (evolutionary tendency towards vision)

14
Q

prosopagnosia

A

neurological disorder that impairs a persons ability to perceive FACES

15
Q

what is damaged in prosopagnosia

A

the frusiform gyrus (face recognition area)

16
Q

parallel processing

A

processing multiple things at once (depth, colour, etc)

17
Q

what are perceptual sets

A

pyschological factors determing how we perceive our environment

18
Q

what does the v1 detect

A

orientation/direction

19
Q

v1 cortical simple cells

A

oblong reeptive fields to detect tild/directions at specific locations
combine input from multiple ganglion cells

20
Q

v1 complex cortical cells

A

correspond to SEPCIFIC tilt/direction ANYWHERE in RF

21
Q

v1 hypercomplex cortical cells

A

correspond to particular tilt/direction AND ENDS of a line

22
Q

retinotopic organization of v1

A

left to right and right to lef corresponded

v1 is organized into ‘maps’ that correspond to each other

23
Q

how was cross processining discovred

A

bullet wounds in soldiers; they could not see SPECIFIC parts in a visual field due to lesions in that area (left or right)

24
Q

what are blobs

A

segegrated processing of colour

25
Q

mach band illusiosn

A

different brightness bands that contribute to seeing edges as off center/on center cells either fire or illuminate

26
Q

on centre cells and light

A

if light covers center= lot sof neuron firing
if light in surroundings= inhibition of firiting
if light in BOTH centre and periphery= some firing

27
Q

centre surround opponency

A

occurs in LGN cells= lgn cells change firing rate MOST when they encounter changes in an image to detec edges

28
Q

why are edges important

A

correspond to important things (otlines)
recognize objects
used even in computer vision (edge detection algorithims)

29
Q

dorsal stream: what for

A

CONTROL of behaviour (“WHERE/HOW”)

30
Q

ventral stream; what for

A

CONSCIOUS perception (THE “WHAT)

31
Q

difference between dorsal and ventral streams

A

the “WHERE vs WHAT Theory”: how information is used after it arrives

32
Q

damage to dorsal stream cuases…

A

optic ataxia

33
Q

optic ataxia + example

A

occipital pareital region damage where a woman can’t GRASP an object she sees

affects control of behaviour

34
Q

damage to ventral stream causes…

A

visual form agnosia

35
Q

visual form agnosia + example

A

patient DF can grasp an object under direction that she can’t regonize due to damgage in ventral prestriate cortex

affects concsious perception

36
Q

what is visual agnosia

A

conscious perception of the world and recognition of an object (light, pose, position, etc)

37
Q

how do we see objects

A
  1. different types of objects (light, etc)
  2. different versions of an object= degraded/ dilluted/noisy, etc

but humans due to edge perception can still recognize often

38
Q

who was oliver sacks

A

patient with visual agnosia; can’t identify a rose but uses OTHER ways of identifies it such as memoery and smell

39
Q

how do we precieve motion

A

images move into retina

  1. because we move our eyes
  2. because the subject moves
40
Q

what area of the visual system detects motiion

A

v5/Mt

41
Q

akinetopsia

A

lesions/damage to v5 that cause motion blindness; you only see ‘stills’ of the world

42
Q

Salzman and Newsome 1994

A

did experiments on rhesus monkeys and looked at direction of perceieved motion

43
Q

Salzman and Newsome 1994 set up

A

iv= activit from V5 cells to different directions

dv= manipulation of the electrically stimualted cells

44
Q

Salzman and Newsome 1994 results

A

monkeys overrpoerted seeing motions in cells in preferred direction

45
Q

human and v5 exerpiments

A

place participants in fMRI scanner and see how V5 responds differently to moving stimuli

46
Q

motion after affect illustion

A

after your v5 fires after a moving image to look at a still image illusion= you might still perceive motion as relative activity in pairs of neurons still firing due to prolong stimulation of one neuron that decreases the response of the other

47
Q

how is perceived motion determined

A

by relative activity in the pairs of neurons in v5 turned in oppostite directions

48
Q

stationary objecst and v5 neurons

A

opposing pairs of neurons are balanced (fire equally)

49
Q

downard motion and v5 neurons

A

cells corresponding to UP dont fire and to down fire a lot

50
Q

stationary objects after v5 neurons

A

down neurons firing a little due to prolonged stimulation adapation= results in an unbalanced respones of neuron detections= perception of V5 affected

51
Q

what does V4 do

A

shape, colour, curvature, orientation

52
Q

what does the inferotemporal cortex do

A

responds to COMPLEX objects and faces

neurons have ‘shape preferences’ according to macaque studies

53
Q

fMRI studies and V4

A

faceselectivity area= object represenation

found that localized brain areas for faces and chairs in a study

54
Q

visual prosopagnosia

A

face selectivity/recognition disorder

objects still recognized

55
Q

where is visual prosopagnosia damage

A

right fusiform gyrus

56
Q

face seelectivity

A

differentaiton between faces + objects

57
Q

face selectivity studies

A

electrode implants stimuations cause faces to metaphormpizes in front of patients

fmri show activiy in frusiform face area to faces

58
Q

face-specificity studies hypothesis

A
  1. domain specify

2. expertise hypothesis

59
Q

domain specitify hypothesis

A

facial recognition is INDEPDENTN from object recognition since birth

60
Q

expertise hypothesis

A

general object processing mechanisms in brain become ‘fine tuned’ to faces due to experience

61
Q

face-specific inverstion effect

A

its harder to remember upside down faces

features

62
Q

dog breeders study (diamond-carey 1986)

A

supports expert hypothesis; demonstrates inverstion effects

experts (dog trainres); stronger inverstion effect to upside down images of dogs than novices

63
Q

holistic processing of upright faces

A

WHOLE greater than the SUM of PARTS

we dont look at individual faces but WHOLE faces

studies how its easier to recognise a face with just HALF than a HALF + FALSE half (composite effect)

64
Q

how are inverted faces processed

A

not holistically= no composite effect

65
Q

inversion effect

A

The face inversion effect is a phenomenon where identifying inverted (upside-down) faces compared to upright faces is much more difficult than doing the same for non-facial objects.

the face inversion effect requires an underlying face-specific mechanism to produce it

66
Q

other race studies and signifiance

A

rhodes; looked at how european caucaisans and chinse faces had the inverstion effect with each other

demosntrates europeans better at recognizing european faces than chinese and vice vera

no inversion effect in a chinese face but yes inversion effect in a european face

supports idea of experience and holistic prorcessin (expert effect)

67
Q

where vs what theory

A

dorsal sptream for visual spatial perception

ventral stream for visual patttern recognition

68
Q

control of behaviour vs conscious perception theory

A

dorsal stream for visually guided behavior

ventral stream for conscious visual perception

69
Q

critiques of vision for action/perception

A

Perception—> conscious experience of seeing
but need to also include ‘unconscious/preconscuious’
- represents visual experience of world but not the foundation for action
- it influences action but has adaptive value as link between perception and action is indirect/flexible as memory/planning play a role

70
Q

patients with spatial neglect

A

information is presented to the unattended side of the visual field that still influences cognitive tasks.

71
Q

action planning

A

by the ventral stream (provides visual information to enable identification of a goal object and OTHER cognitive systems plan the action to pick up that cup)

72
Q

vision for action

A

orsal stream: use current information (visual) about the size/shape/disposition of an object to program and control the skilled movement to carry out action

73
Q

allocentric perception task

A

Patient D.F. was asked to make a verbal judgment as to which of two stimuli was closer to a reference point located between them.

74
Q

The ‘egocentric perception’ task.

A

Here patient DF was asked to make a similar judgement, but this time her forefinger was located at the reference point.

75
Q

The ‘allocentric motor’ task

A

in which the patient was asked to make a pointing response from an arbitrary start point to mime the location of the test stimulus with respect to the reference point

76
Q

) The ‘egocentric motor’ task

A

in which the patient was asked to make a direct pointing response from a start location to a target stimulus