Week 4

Question 1

True or false: newborns see well enough to perceive “faces”

Answer 1

True, Johnson et al. (1991) found that a paddle with a schematic of a face as opposed to blank/scrambled caused infants to turn their heads more often to it

Question 2

Define acuity

Answer 2

perceiving fine detail

Question 3

What is the adult snellen test

Answer 3

eye test used for adults with rows of letters progressively getting smaller in size further down to test acuity

Question 4

Testing visual acuity in infants: what is reflexive following? (optokinetic nystagmus)

Answer 4

little gradings (lines) move back and forth where the test is to see if infants follow it (you can modify the sharpness of the gradings)

Question 5

Testing visual acuity in infants: what is visual paired comparison?

Answer 5

-uses two stimuli e.g. grey circle and lined circle to see how much detail the infants perceive/prefer

Question 6

What are babies clinical vision like from newborn-8 months?

Answer 6

NB-20/660 (what adults could see 660 ft away, babies would need to see 20)
2 mos-20/300
8 mos-adultlike vision

Question 7

How does acuity improve for infants?

Answer 7

-develops over the first few years of their life
-improvements in perceiving high spatial frequency (fewer spaces between lines e.g.) and low contrast info (not the contrast of black and white as strong more grey e.g.)

Question 8

How does the case study of Virgil demonstrate that visual development is dependent on visual experience?

Answer 8

-Sacks (1995) said virgil was a man with dense cataracts since childhood potentially always having poor vision
-got them removed when he was middle-aged
-still unable to interpret much even if the visual stimulation became available to him demonstrating we “learn to see” (didn’t get chance to learn much due to cataracts blocking portion of light into eye)

Question 9

Which area is our vision most acute?

Answer 9

the fovea

Question 10

What’s the job of the lens?

Answer 10

to bend the light to focus on the retina (including the fovea)= accomodation

Question 11

Why is it important to remove the cataract as early as possible?

Answer 11

-by removing the cataract and inserting a lens it gives a better opportunity for the eye to connect/transmit visual input to the brain
-the normal eyes connections get stronger and stronger through experience whereas the cataract eyes connections will get weaker and weaker due to lack of usage if not removed to force the connections to become useful
-plasticity occurs

Question 12

True or false: corrected cataracts result in small deficits in face perception (using configural information ) as adults (LeGrand et al., 2001)

Answer 12

True the corrected eye will not be on par to the normal healthy eye most times
-people with corrected cataract can recognise different features just aswell as people who had no cataract but poor in recognising configurated faces (same internal state but different arrangements)

Question 13

True or false: changes in visual acuity aren’t strongly dependent on experience.

Answer 13

false changes in visual acuity (plus face perception/recognition) ARE strongly dependent on experience

Question 14

How do infants interpret info about objects perceived in the environment?

Answer 14

-they’re biased to attend to the contours of high contrast e.g. edges of an object (helpful perceiving its outline)
-they perceive things as coherent entities aka object unity

Question 15

What did Spelke find in relation to infants distinguishing an object from its background?

Answer 15

-3 mos look longer at “impossible” event (part of an object moves with background) than a “possible” event (object moves separate from background)

-3 mos look longer at “impossible” event (grasping part of an object results in only part of it moving like a chunk) than to a “possible” event (entire object moves when grasped)

Question 16

How do infants perceive partially occluded objects according to Kellman & Spelke (1983)?

Answer 16

A partly covered rod moves behind a stationary box
* After habituation (diminishing of innate response), 4-month-old infants longer at the broken rod (i.e. perceive object unity),
but ONLY if the rod is moving
* Newborns look longer at the complete rod. (innate response)

Question 17

What factors support perception of object unity? (perceptual completion)

Answer 17

1.common motion (when in motion infants/adults fill in missing gap i.e., perceptually complete it)
2.width of occluder (occluder is the thing the object is hiding behind e.g. a box so if proper wide e.g. you see two hands come out, the wider it is the less likely you think its just one person because less for visual system to infer)
3.shared orientation (clean spatial relationship between two parts=visual system more likely to fill it in)

Question 18

How can object perception lead to illusions

Answer 18

typically involves some “interpretation” of sensory stimulation based off past experience and can be adaptive BUT can fill in stuff that’s not there (illusions)

Question 19

How is category knowledge tested in infants?

Answer 19

-visual perception usually tested with a visual preference task
-exposure to an image multiple times (e.g. cat) then present it with novel picture (e.g. dog)
-preference for novel picture=evidence of distinguishing/categorising AND also remembered previous familiar one (encoded it and recognised hence wanting to look at new one as already seen)

Question 20

What is the preference task for categories: familiarisation test (testing categorisation knowledge in infants)

Answer 20

-familiarises infant with a set of individuals from the same category e.g. different cats
-then test them on a new cat they haven’t seen and a dog
-look longer/preference for dog picture=recognised cat is familiar and from same category despite also being new so wanting to see something else (in this case the dog)
-see this in 3-4 mos seen in Quinn & Eimas, 1996 Habituation test (just the test described above) although when it was dogs that were familarised, infants was more unsure whether the cat/dog belonged to the category shown

Question 21

Can other categories be used when testing categorisation knowledge in infants?

Answer 21

Yes you can use spatial relationships above, below, in between (Quinn, 1994/Quinn et al. 2003)

Question 22

Define object permanence

Answer 22

the “knowledge” that objects exist continuously in time and space independent of whether they can be directly apprehended (seen, felt, tasted, etc.)

Question 23

True or false: infants sometimes behave as though they lack object permanence.

Answer 23

True

Question 24

What do infants’ know about the
permanence of objects?

Answer 24

Piaget (1954): infants under 9 months don’t search for hidden objects because they lack knowledge of object permanence. (what they see is what they see) they experience the world in the “here and now”, rather than being able to represent it mentally, and reason about it.

Question 25

Explain the development of object permanence in infants

Answer 25

*Initially: “out of sight is out of mind” *At 4-8 mos, infants will retrieve a hidden object if partially visible -At 8-12 mos infants often reach for hidden objects but still appear to have some limitations in object permanence (the A-not-B error) ■At 12-18 mos infants stop making the A-not-B error, but have difficulty with invisible displacements (cup with object in then cover over it. if object found to not be under cup infants don't know where to look) ■By about 24 mos they start to successfully track objects through invisible displacements

Question 26

What's the A-not-B error?

Answer 26

-2 hiding locations -initially object hidden under one location which infant often correctly finds acknowledging objects existence -move to 2nd location=infant still look to 1st location (aware of existence but uncertain where)

Question 27

Are infants really ENTIRELY bound to the here and now? i.e. why do people disagree with Piaget?

Answer 27

■Baillargeon (1987) thought Piaget’s task UNDERESTIMATED infants’ true understanding of object permanence (in relation to their development of object permanence.) –Coordinated reaching and grasping are hard. –Combining the acts of removing a cover and then grasping an object is REALLY hard.

Question 28

What did Baillargeon (1987) habituation experiment involve?

Answer 28

-4.5-month-old infants were habituated to a rotating screen. -showed possible event and impossible event

Question 29

What were the results of Baillargeon (1987) habituation experiment?

Answer 29

-they look at impossible event longer -do look at possible event but get disinterested quicker after a few times -in the control condition with no box the results were the same -shows they may know something about object permanence earlier than believed using fewer motor demands (unlike Piaget's ideas)

Question 30

What is the controversy over object permanence?

Answer 30

infants tend to show “understanding” or “knowing about” object permanence in “looking” tasks earlier than they do in reaching tasks BUT there is controversy over what differences in performance across tasks means.

Question 31

Why do infants fail in reaching tasks but succeed in visual tasks?

Answer 31

A “knowledge” driven account of performance aka Baillargeon (1987) suggests infants “understand” object permanence – it's KNOWLEDGE of a principle that they can use to reason (logically) about events * Developmental change is SEPARATE from object permanence itself as change/success on object permanence tasks is due to better reaching, mastering things other than object permanence (i.e. to developing reaching skills).

Question 32

Explain object permanence: A Representational Persistence or Process-Oriented Account

Answer 32

■takes issue with idea that performance on object permanence tasks reflects infants’ “understanding” is a physical principle or law. ■Instead, it suggests “object permanence” is similar to a visual illusion in which the visual system automatically fills in missing information, and this is easier as a function of experience and familiarity with objects and how they behave.

Question 33

What occurred in Shinskey & Munakata's (2005) experiment?

Answer 33

-put object in front then turned the light off -looked at extent infants would reach out for object in the dark and familiarised them to one object in condition

Question 34

What were the results of Shinskey & Munakata's (2005) experiment?

Answer 34

-lights on=novel object more interested in -lights off=familiar object more of interest -suggests infants can sustain representation of that space when they have visual experience of that object hence why when light off=familiar object whereas in the novel object the visual system fails (supports representational account)

Question 35

What do these findings mean for accounts of object permanence? (Shinskey & Munakata's 2005)

Answer 35

-familiarity of an object influences performance on an object permanence task because they're more easily represented by the visual system when not in view – representations of objects are graded in strength and persistence. -“object permanence” reflects not an abstract emerges (like illusions) based on how the brain ACTIVELY constructs a representation of the environment based on visual input, including filling in info that isn't directly perceptible (similar to object unity). -Infants are still developing the ability to form and maintain representations of their environment, and do so more readily for objects they have more experience with.

Question 36

(Johnson et al., 2003a) Experiment 1 + Experimental logic:

Answer 36

-ball shown back and forth and goes out of view moving past box(continous=move back and forth never going out of view/discontinuous=just shows what was viewed) infants perceive the ball as a continuously moving object=look longer (be surprised) at the discontinuous display. perceive the ball as a discontinuous object= they will look longer at the continuous display

Question 37

(Johnson et al., 2003a) Experiment 2 Results + Experimental logic:

Answer 37

-occluding panel narrower in this instance If 4 month infants perceive the ball as a continuously moving object, they will look longer (be surprised) at the discontinuous display. (2 months didn’t do this however) In contrast, if they perceive the ball as a discontinuous object they will look longer at the continuous display.

Question 38

(Johnson et al., 2003a) Experiment 3 Results

Answer 38

4-month-olds’ preference with narrow (12.1 cm – 67ms), medium (14.8cm – 533ms), and wide (17.7m – 667ms) occluding panels.

Question 39

Johnson et al. (2003b) conclusions

Answer 39

■Infants’ ability to represent objects develops between 2 and 6 months. ■performance is consistent with a “representational persistence” account – the more information the visual system has to fill in, the less likely it does so successfully.

Question 40

Johnson et al. (2003b) procedure

Answer 40

Infants watch 8 trials, each of which contains 6 complete occlusion cycles. Used eye tracker to test if infants would anticipate ball moving to the other side.

Question 41

Johnson et al. (2003b)

Answer 41

6-month-olds anticipate more often than 4- month-olds (who don't anticipate at levels greater than chance but with practise and familiarisation they could show some)

Question 42

Elaborate on this statement "Visual Experience with UNOCCLUDED Trajectories supports the emergence of “object permanence”"

Answer 42

■Visual perception is strongly driven by experience – what we “see” in the moment influenced by what we have seen (and learned) in the past. ■In the case of object permanence in these tasks, the visual system learns to fill in missing information about object motion BASED ON PRIOR EXPERIENCE WITH SEEING OBJECTS MOVING ACROSS SPACE AND TIME. ■This is what object permanence is, not a logical inference.