PSY2002 SEMESTER 1 - WEEK 5

Question 1

what is Moravec paradox

Answer 1

reasoning (high-level cognitive tasks) relatively easy to be implemented in a machine compared to other task like perception, action (low-level cognitive tasks) that are surprisingly hard to be implemented in machines

Question 2

summarise Moravec’s paradox

Answer 2

computer good at “hard task” (chess)
bad at “easy task” (walking)

Question 3

what does blocking all touch sensations from fingers do

Answer 3

doesn’t affect motor control but make movement difficult/clumbsy
multisensory integration of touch and vision for feedback to know that we have grasped match and where our matchbox is

Question 4

we can replicate tactile/visual sensor in robut, but where do issues lie

Answer 4

how to replicate multisensory integration = how to integrate info from visual and tactile systems

Question 5

name 2 challenges for multisensory integration

Answer 5

1. how to transform representations from different senses into common representation
2. how to integrate info from different senses in coherent percepts

Question 6

what is the visual reference frame

Answer 6

eye-centred/retinal (location of visual stimulus on retina)

Question 7

what is the audition reference frame

Answer 7

head-centred (location of sound source with respect to ears)

Question 8

what is the touch reference frameq

Answer 8

body-centred (location of tactile stimulus on skin)

Question 9

do reference frames move independently or in sync

Answer 9

move independetly, meaning info they gather can be v. different
and body needs to convert between reference frames to external space (coordinate)

Question 10

when converting from eye-centred reference frame to head-centred reference frame what do we need to know

Answer 10

orientation of eyes

Question 11

when converting from head-centred reference frame to body-centred reference frame what do we need to know

Answer 11

orientation of head

Question 12

what does converting btw/ reference frame in general require us to do

Answer 12

know position and orientation of body part = body schema

Question 13

input coming in from 2 different sense (hear and see dog, if dog moves, representation moves in both frame). if dog is central, what is position of visual/auditory reference frame

Answer 13

visual (eye-centred) = dog in middle
audition (head-centred) = dog in middle

Question 14

input coming in from 2 different sense (hear and see dog, if dog moves, representation moves in both frame). if dog moves, what is position of visual/auditory reference frame

Answer 14

visual (eye-centred) still straight as head hasn’t moved only eye has
audition - head hasn’t moved meaning dog no longer in centre of head-reference frame

Question 15

input coming in from 2 different sense (hear and see dog, if dog moves, representation moves in both frame). if dog is central, but head moves what is position of visual and auditory reference frame

Answer 15

visual frame moves (looks away) = dog is no longer central
but still central for auditory

Question 16

define body schema

Answer 16

internal representation of positions of body parts in space, which is updated during body movement
includes posture, spatial extensions
(at any given moment knows where all limbs are so doesn’t need visual input)

Question 17

explain how body schema is spatially coded

Answer 17

position of each body part in external space

Question 18

explain how body schema is modular

Answer 18

different body parts processed separately

Question 19

explain how body schema is updated with movement

Answer 19

automated and “always on”

Question 20

explain how body schema is adaptable

Answer 20

changes when body changes

Question 21

explain how body schema is supramodel

Answer 21

combines input from multiple senses eg, proprioception, touch, vision, audition

Question 22

explain how body schema is coherent

Answer 22

spatial continuity when resolving perceptual conflicts (everything that is part of body is always attached to body, never have feeling of arm not attached)

Question 23

explain how body schema is interpersonal

Answer 23

observed actions are represented within same body schema = viewing someone elses actions, automatically represent this within own body schema to copy if we need

Question 24

compare body schema with body image

Answer 24

schema= sensorimotor representation guiding action and doesn’t require awareness
image= how you imagine your body, feel about it and consciously represent it

Question 25

name two bodily illusions

Answer 25

pinocchio illusion rubber hand illusion

Question 26

what is pinocchio illusion

Answer 26

1. vibrating bicep activates same receptor, make arms feel extended 2. point to nose 3. if arm extended then nose feels super long

Question 27

what is rubber hand illusion

Answer 27

ppt real hand hidden, stroke real and rubber simulataneously ppt see and feel rubber hand = vision and touch undergo multisensory integration, showing us body schema can be modifiable

Question 28

outline crossmodel congruency in rubber hand experiment

Answer 28

larger in rubber hand than non, and virtual body effects suggest visual info about apparent hand position has objective and subjective cross-modal influence on tactile judgement even if vision conflicts with proprioception, but no effect if put in anatomically implausible posture meaning visual info can dominate slightly wrong proprioception (but proprioception reduces impact of vision when visual info inconsistent with proprioception)

Question 29

what is location for neurons responding to visual and tactile stimulation (cortical)

Answer 29

ventral premotor cortex parietal, ventral intraparietal superior temporal sulcus

Question 30

what is location for neurons responding to visual and tactile stimulation (subcortical)

Answer 30

putamen, superior colliculus

Question 31

how can the impact of body posture on perception be studied

Answer 31

vibration on both hands in random order, ppt indicates which hand stimulated first condition: arm crossed/un found ppt mixed up what hand was stimulated when arm crossed = solving task doesn't need input from body schema but body schema is always on, never off (this can be counterproductive)

Question 32

outline how cross-modal integration can be studied

Answer 32

ppt touch block with monitor on thumb/index, receive tactile stimulus, respond with location visual distractor= light close to index/thumb buzz when happening but not always congruent found quicker reaction in congruent>incongruent, suggesting congruency effect exist in both hands, cross modal integration and visual interference but greater effects for same hand

Question 33

is greater interference based on hand location (body schema) or visual field? how is this tested

Answer 33

arm-crossing (change body schema), tactile stimuli on same body side, visual on different as we move arms, effect of visual distractor moves with hand during arm crossing found body schema >visual repres mediates integration between visual and tactile stimulation = means cross-modal interactions mediated by body schema

Question 34

what occurs at 6 months for body schema development

Answer 34

body schema start intefere with tactile orientating baby reach for foot if vibrated cross/un feet, stimulate, see which baby thinks stimulated first 4 months can tell, but 6 month cannot

Question 35

name 3 disorders of the body schema

Answer 35

Alice in Wonderland syndrome autotopagnosia phantom limbs

Question 36

summarise alice in wonderland syndrome

Answer 36

distortion of size perception, microsomatognosia, macrosomatosognsia affecting whole body

Question 37

define microsomatognosia (alice in wonderland syndrome)

Answer 37

body parts appear smaller

Question 38

define macrosomatognosia (alice in wonderland syndrome)

Answer 38

body part appear larger than its true size

Question 39

what is alice in wonderland syndrome associated with?

Answer 39

childhood migraines, head trauma, viral encephalitis

Question 40

outline autotopagnosia

Answer 40

inability of locating body parts and loss of spatial unity of body can name part but relative order lost

Question 41

what is finger agnosia

Answer 41

fused perception of fingers

Question 42

outline phantom limb

Answer 42

still feel limb, can include agency over limb (movement) associate with pain can change over size (shrink = telescoping)

Question 43

define cross-modal congruency effect

Answer 43

performance difference between incongruent vs congruent trial

Question 44

outline research into cross-modal congruency effect using visual lights near same/other hands

Answer 44

incongruent visual distractor delays tactile judgement, shows cross-modal congruency effect is more pronounced for visual distractor near tactually stimulated hands and visual stimuli closest to current hand position produces largest effect on vibrotactile judgement = means combination of retinal visual stimulation and somatotopic vibrotactile stimulation produce largest remaps with postural changes

Question 45

what is a critical factor for spatial precueig

Answer 45

proximity of tactile and visual stimulus in external space

Question 46

outline visuotactile interactions in a patient with brain-damage, who can show spatial extinction

Answer 46

can detect single stimuli regardless if presented on same/different side of lesion but if given 2 stimuli at same time then different side stimuli is extinguished, can also be observed crossmodally

Question 47

whats peripersonal space, and what happens to objects wihtin the area

Answer 47

immediately surrounding body objects within peripersonal space can be immediately grasped/manipulated extent not fixed, can contract and expand (encodes space outside body, incorporates tools into body schema) allows us to figure out what tools we can currently use/manipulate

Question 48

outline tool use when extending our body

Answer 48

tool incorperated into our body schema, and neurons respond to stimuli at far end of tool

Question 49

apply cross-modal congruency effect to tool use

Answer 49

no crossing of body parts, only tools crossed same delay effects as seen during arm crossing

Question 50

if tool held straight, what happen to cross-modal congruency effect

Answer 50

stronger if in crossed position, larger change in spatial nature of visuotactile interaction depend on experience in active use of tool

Question 51

what does extension of visual reference frames of multisensory neurons in tool use suggest

Answer 51

body schema extends along tools, due to multisensory coding of space by intraparietal neurons

Question 52

in research with right-hemisphere patients with cross-modal extinction of touch on left hand by concurrent visual event near right hand, what is found (regarding extintion)

Answer 52

extinction reduces with increased distance away from hand, and effect of using tool decreased with time

Question 53

what can prolonged tool manipulations linking visual events on right to left hand do

Answer 53

have opposite effect of decreasing competitive exctinction between visual event on right and left hand touch after right-hemisphere damage

Question 54

for mirror studies of tactile judgements, what cross-modal effects are found

Answer 54

larger cross-modal congruency effect from visual distractor found for mirror reflection of light near hand than further away but seen directly applied even if light seen close to rubber hand or confed hand opposite mirror of ppt hand suggest mirror reflection of lights near ppt hand recoded as originating from peripersonal space despite same optical properties as distant lights placed beyond mirro