Module 1: Infancy and the Physical World Flashcards
What were Jean Piagets and Henry James earlier theory on child development?
Historically famous developmental psychologists such as Jean Pigaet and Henry James were sckeptical of infants cognitive ability to process information in stimulus rich environments/
(A) Jean Pigaet: - Jean believed that before 18 months of age infants understanding of the world was limited (i.e., they couldn’t hold mental representations in their mind or store information/memories) to what could be observed and acted upon in the present moment.
(B) Henry James: - Henry is known for his quote “infants... feel it all as one great blooming, buzzing, confusion”. This reflected his belief that infants were rudimentery (guided by basic principles) in their psychological understanding of their physical world that they were constantly bombarded with sensory information to the point that they were not capable of interpreting their physical world.
How do we describe infants’ early perceptual world of objects and events? Is it similar to adults’ perceptual capability?
How would we test this? by looking at ___
Why is studying ___ important?
by focusing on infants’ memory!
Why is studying infants’ memory important?
We live in a very busy world with lots of sensory information to interpret which requires time and effort to do. To make this process easier we need to be able to encode and store what we have seen before, so we are able to interpret what is new and develop higher order concepts. i.e., we need good working memory (short-term memory) which gives us the ability to store information over brief periods of time for manipulation. Example: o Where’s Wally is a visual search task which requires working memory to be able to recall where you have searched and what you’ve seen in the past and use this information to help you find him now.
what form of learning gives richer information to infants?
interactive rather than observational.
i.e.,
why their cognitive development becomes more sophisticated once they learn to self sit and interact with their physical world to learn about how objects ought to be.
i.e.,
why their memory of associations is longer for the mobile task relative to the defferred-imitation task.
How do we test infants working memory capacity to recall information about their physical world?
Cornell (1979) > Logic, > Steps, > Results, > Implications.
Cornell (1979)
Conducted a study to test the bounds of infants working memory. They exploited infants’(5–6- month-old) preference to pay attention to new things (adaptive function to learn new things; preference for novelty) and used this to see how they can store information about objects.
Logic: If infants can remember what they saw in the learning phase of the experiment than they should express a novelty bias and look longer at the new image. However, if they cannot recall what they saw in the past then there should be no significant difference in looking across the two stimuli and conditions.
Steps:
1. Learning Phase: • Infants were habituated to a pair of images of geometric shapes (3 sets, for 20sec each). This means they were repeatedly exposed to the images till the infant got bored and stopped paying attention to it.
2. Reminder Phase: • Two days after the learning phase infants were shown one of the two images as a reminder of the learning phase.
3. Test Phase: • This is a recognition test where they were shown either a familiar; familiar pairing or a familiar; novel pairing and their looking time was compared between the two conditions.
4. Results: • They found that 5- and 6- month-old infants showed a novelty preference and looked longer at the novel image within the familiar; novel pair. • This implies that infants 5–6- month old's have good recognition and memory of objects and can retain visual information for at least 2 days.
*memory is not due to reminder cue because the control group who received a “reminder” cue without being familiarized to some of the stimuli did not show a novelty preference. *same effect with faces as well. *evidence of recognition memory of objects in early infancy
Using Novelty Preference to Measure the Span of Working Memory in Infants.
i.e., how many items can infants hold in their working/short-term memory?
Rose et al. (2001) > Logic > Steps > Side Notes > Key Points
Rose et al. (2001)
Conducted a study to examine how many items infants can hold in their working memory as they developed. They tested the same infants at ages 5, 7 and 12 months to see if they’re able to hold up to 4 items in their working memory (short-term memory).
Steps:
1. Infants were familiarized
(habituated) to 4 items in
succession (one at a time).
2. Then infants were shown each of the 4 items (old) but each paired with a novelty item. The researchers were interested in whether, across the 4 object pairs, did infants spend more time looking at the novel object?
3. They found that 5-month- old infants had a working memory span of 2 but by 12 months they had a working memory span of 4 (i.e., it was developing!).
Notes: Span of 1 = novelty preference shown in only one pair, Span 2 = novelty preference seen in two pairs so on and so forth... They tested for primacy and recency effects. Working memory capacity increased with age (i.e, between five and seven months only a few infants, 25%, could hold 3-4 items simaltaneously in working memory. By 12 months almost 50% of infants could hold 3-4 items in their working memory). Recency effects found across all three ages. No primacy effect was reported but is probable.
Key Takeaway? This shows use that exploiting “novelty preference” and habituation techniques we can provide evidence that infants can encode, store, and manipulate visual information about objects in their physical world for 2 days and test the limitations of their working memory capacity. Working memory operates similarly in infants as it does in adults.
Memory for Causal Events: Can infants remember that objects are affected by our actions (causal events; cause-effect relationships)
Are infants able to
remember cause-effect
relationships? How do we
test this?
Are infants able to remember cause-effect relationships? How do we test this? Using tasks that teach infants that an action (kicking) causes a desirable effect (spinning and sound). Then later testing to see if the infant will engage in the action to get the effect (conditioned response).
Rovee-Collier & Hayne (1987)
Mobile-Kick Study
Steps: 1. Baseline Phase: Where the infant has a ribbon tied to their ankle whilst in the crib. The researchers keep a record of how many times the infant kicks their leg in the absence of reinforcement (i.e., the mobile moving).
2. Learning Phase: Immediately after baseline the ribbon connected to their foot is attached to the mobile. Any kicking action will move the mobile and plays sounds, this acts as a reinforcement for the behaviour. Infants will learn cause-effect relationship between kick-mobile and their kick rate will increase (ABA design; baseline- reinforcement-baseline).
3. Long-Term Retention Phase: The researcher tests infant's memory of the causal event by testing the infant's behavioural response when place in the crib where the ribbon is connected to an empty stand (i.e., doesn’t move) several days later. The kick rate is compared to baseline (if increases it provides evidence of working memory of causal events! If below baseline no memory of causal events to days later).
Results: MAIN FINDINGS 2-month-old infants are able to remember causal events (kick-mobile) up to 2 days. 3-month-old infants are able to remember causal events (kick-mobile) up to 1 week. 6-month-old infants are able to remember causal events (kick-mobile) up to 2 weeks.
*This provides evidence that their ability to remember causal events are present in early infancy and their working memory capacity develops overtime.
Can the Mobile task be conducted on older infants?
Can we use the SAME mobile experiment for older infants? No. o But we can adapt it so older infants sit up right on a chair rather than lying down. Still infants are testes to see if they kick their legs to make objects (toys: train move or mobile spin) move. Results: o plotted on top of the mobile task we see a clear age- related pattern where the older infants are the longer, they can hold information about causal events over time.
The Main Debate About Rovee-Collier & Hayne’s (1987) Findings?
Mobile Task?
The Main Debate About Rovee-Collier & Hayne’s (1987) Findings?
Procedural or Declative Memory?
Do the findings of the mobile task is reflect procedural memory (implicit, automatic, memories of how to perform different actions or skills) or declarative memory (explicit, episodic memory which involves bringing memories into conscious awareness and manipulating them). How do we determine if its merely a reflexive action or thought-out response?
One way to test this is to explore the boundaries of the task and rule out other factors that may influence their performance.
How do Rovee-Collier et al. (1992) address the debate around their findings on their mobile task?
describe the two follow studies they conducted
Does it work like adult memory? do changes to contextual and stimuli factors impair recall of explicit memory?
Rovee-Collier et al. (1992)
Changing the features of the stimuli between the learning and test phase.
Steps: 1. 3-month old infants were trained on the kick-mobile contingency with a mobile that had blocks with the letter L on them. 2. 24-hours later they were tested to see if they would kick to make the mobile spin when the blocks were changed from “L’s” to “X’s” 3. Results: Changing the features of the stimuli disrupts infants recall completely. Only when the stimuli stays the same are they able to recall the contingency kick-mobile.
Logic: If prelinguistic infants are effected in the same way as older primary school children (approx. 6 years old) to changes in stimuli than this indicates that they have very similar working memory systems. Argument for prelinguistic infants using explicit memory rather than procedural!
Rovee-Collier et al. (1992)
Changing Features of Learning Context
Steps: 1. 3-month old infants were trained on the kick-mobile contingency in a crib with stripes on it. 2. 24-hours later they were tested to see if they would kick to make the mobile spin when they were placed in a crib with polka dots on it. 3. Results: - Infants were not able to recall the kick-mobile causal contingency! - This indicates that specific details of the environment can act as retrival cues (memory in early infancy is context-specifc) - From 9-months of age infants memory becomes less context specific. This coincides with their development of motor and language skills that make them more cognitively flexible (interacting with objects, language to communicate; are less constrained by info only being given in restricted contexts). - Changing contextual factors impacts explicit memory for infants, preschoolers and adults indicating they have similar memory systems!
Summary of the Procedural vs Declaritive Memory Debate:
It is difficult to measure explicit (declarative, conscious) memory in infants, but some scientists argue that since the factors that impact adults’ explicit recall (like the changes to feature of stimuli, context, or length of retention interval) also affect infants’ memory during long-term recall, then long-term recall on the mobile task must tap declarative memories.
Can forgotten memories become accessible again if appropriate cues are given?
Rovee-Collier (1993) use a __ paradigm
reactivation paridigm
Rovee-Collier (1993)
What happens when you extend the time between learning and test phase? (gradually information is forgotten and infants become more dependent on contextual cues to trigger memories; much like adults)
How do we test this? Use a reactivation paradigm!
Reactivation paradigm
A procedure in which the participant, usually an infant, is given a reminder of an earlier learned, but apparently forgotten, memory
that enables this memory to become accessible again.
Steps:
1. Baseline.
- Teach mobile-kick
contingency
3. 3-month old's who have forgotten the kick-mobile relationship after a delay of 1 week (kick rate falls close to baseline in delayed retention phase)
- The reactivation phase
consists of a reminder that
pulling on the ribbon makes
the mobile move (reminder) - 24 hours later test whether
their kick rate increases from
close to baseline.
6. Results: They found that after the reactivation phase, it triggers the memory again, and the infants kick rate increases from baseline. Test was successful and by providing an appropriate cue you can recover memories and observe the kicking behaviour. With reminder, 3- month-olds show intact memory of causal connection even at 28 days after original training. Two month old infants up to 14 day delay and by six months old infants can recall the contingency up to 3 weeks. This can also explain childhood amnesia- why without cues to trigger or reactivate memories they’re forgotten.
**young infants are able to develop long-term memories of causal events or contingencies with the help of retrival cues. You can recover lost memories. Young infants can develop long-term memories for causal events and memory retirval is governed by the same retrival cues for infants as in adults.
Memory of Causal Events Without Explicit Instruction Events where the causal relationship is not shown but we are told that A = B and A = C, we can infer that B must = C (even though we were not told that B = C). Are infants able to do this? Remember relationships that are not explicitly shown as being causal?
Yes. We can use the puppet deferred-imitation task
Barr, Rovee-Collier & Campanella (2005)
Steps: 1. Infants (3-6 months) are shown two puppets (A& B) to build an association between them. 2. A couple days later, we show one puppet a 3-step sequence with the puppet (A) remove the mitten from the puppet, rattle it to make a sound, and them place it back on the puppet. 3. A day later we test whether infants will imitate the 3-step sequence on the target puppet (B).
Logic: Can infants remember what they saw and apply it onto a target stimulus (B) which the association was NOT taught.
Results: 6-month old's pass the deferred imitation task and copy the actions of (a) on puppet (b) for up to ten weeks after the initial exposure. 3-month-old are only able to pass the deferred imitation task if they’re given a reminder cue before the test (i.e., show mitten rattles).
Implications: Infants can generalize memory and their learning of ordered events onto new stimuli even when the causal relationship is not explicitly shown. Only if (A) & (B) shown together and not separately!
Basics of the Puppet Deferred-Imitation Task:
1. Show that puppet (a) = (b)
2. Teach the 3-phase
sequence with one of the
puppets. (A = X; sequence)
3. Test whether they can
imitate sequence (x) taught
on A on the target puppet
(b). In other words, if A=X
and A=B then B=X.
*Provides evidence that infants can remember a sequence of actions and imitate it on novel stimuli! Infants’ imitation is much more sophisticated than we once thought.
Infants can even form more complex associations between memories of objects & events that are physically absent. Infants can even form more complex associations between memories of objects & events that are physically absent.
Cuevas, Rovee-Collier & Learmonth (2006)
Cuevas, Rovee-Collier & Learmonth (2006)
Steps: 1. Infants (6-months old) were shown that puppet (a) = (b) 2. They were then taught a causal relationship within a specific context (kick-mobile in patterned crib) 3. They were then shown one of the puppets above the crib to build an association between puppet (a) and the mobile-kick and crib pattern (3 items of information). 4. If babies can remember if puppet (A) = mobile context which should be remembered for up to 2 weeks, then we should be able to trigger the mobile- kick action when they show them puppet (b) in test phase (puppet a = b). 5. To test whether infants have transferred the association from puppet (a) to puppet (b) we get the 6-month old’s to watch a (3) sequence event with puppet (b) (take mitten off, rattle it, put it back on). Two weeks later they tested whether they recalled the 3- step action after 2 weeks. *the memory of mobile should exert a spreading effect and guide recall of puppet b for two weeks.
Main point:
Babies can form complex associations; puppet a knowledge is transferred to puppet b (mobile= a, a=b). They can understand that events are complex and interconnected and this is reflected in their encoding of the event.
**If both puppet become linked to the mobile-kick context which they will recall for 2 weeks (A=B, A transferred onto B). Than any information about puppet (b) that will inadvertently be added to the mobile connection should also be recalled for 2 weeks. **associative learning, spread of activation = grouped assosication.
Why are we learning about how sophisticated infants’ memory is?
The information is strikingly different for what most people and previous developmental researcher’s assumptions of preverbal infants’ cognitive capabilities. They can encode, recall and manipulate knowledge from past experiences to help navigate their physical world full of stimuli.
Attention & Memory tasks tells us that they can hold memory representations of events which are causally connected, and not explicitly shown causal events (i.e., complex).
Helps them process and encode the vast stimuli in their environment. Memory development suffers when they’re in stimuli impoverished environments (less interconnected, less developed working memory, less recall) than stimulus rich environments.
what are the different ways to study memory in infants?
the mobile task differed imitation or a combination of both.
How might we even directly test whether infants are using visual information to guide attention?
Use the attentional pre-cueing task for infants
Gilmore & Johnson (1995)
Steps: 1. Fixation: Infants are encouraged to focus or fixate on the center of the screen (i.e., stimuli in center screen). 2. Cue Present: A second stimuli or warning cue is presented on the left or right of the center screen. 3. Cue Absent: The warning stimuli is removed from sight. 4. Time Out: All screens are blank, 5. Show Targets: A target (i.e., toy) is presented on either the left or right side of the center screen.
Logic: The warning cue signals which side of the screen the target will appear. If infants can pay attention to this cue and benefit from it, we should see them look for the target on the same side of the screen they were shown the warning cue.
Results: 6-month-olds show (even from delay phase onwards) preference to look at cued location side over delays for 3-5sec.
Implication: Infants’ can maintain (or remember where the cue was and use this information to plan where they will look next; update their working memory) a representation of spatial location of cue (i.e., suggests early operation of working memory), and infants use the information in working memory to plan eye movements.
Attentional pre-cueing task converted to suit adults?
Attentional pre-cuing task used with infants is based on Posner et al.’s (1978) classic pre-cuing task used for adults.
Converted into a video game for adults.
Steps:
1. Participant is asked to
concentrate on the white
cross in the centre of the
screen and use the left or right
arrow keys to select which
side of the screen they see a
white box appear.
2. However, the outline of a
white box acts as a warning
cue which appears on either
the right or left hand side of
the screen before the white
box is shown.
3. The question is whether
people are able to respond
quicker if the warning cue
matches the side the target
white box is presented
(congruent=faster;
incongruent=slower).
4. To avoid boredom of
participants which can have
negative impacts on the
results. Researchers turned
this into a video gain which
exploited adults motivational
system to work for rewards.
5. The centre screen is
transformed into a floating
path in space the character
runs along (enjoyment), collect
bananas for a monkey
(reward) and defeat enemy
space ships by hitting left or
arrow keys (warning and
target cues).
Important Note: The pre-cure trial can either be valid or invalid. o Valid pre-cure trial: - Where the warning cue indicates where the target stimuli will be presented. If your paying attention to the warning cue your focus should be on that side of the screen and your reaction time to the target cue should be quicker. o Invlaid pre-cue trial: - Where the warning cue doesn’t tell you the correct side the target cue will be presented. In this case your attention will be on the worng side of the screen and your reaction time will be slower.
Findings: Same results to Posner et al.’s Attentional pre-cuing task in both infants and adults! Infants reaction times are longer in the invalid pre-cue condition relative to the valid pre-cue condition.
Implications: Infants and adults pay attention to a location information paying attention to a location improves your ability to respond to stimuli there. A skill used in adults is present in infants as young as 6 months old.
How are infants able to discriminate between visual information?
How would we study this?
what are the three ways?
(1) Visual Preference
Technique
Fantz (1961;1966)
o We know that 7 month old infants have a preference for looking at complex images with high visual contrast (blue check and blue swirls) which implies that they pay attention to images they can see well. They can visually discriminate between the blue and white check pattern relative to a blue square. o Using this technique Fantz also showed us that infants as young as 2-3 months show a visual preference for schematic faces (human faces over circles; a . predisposition I infants to pay attention to human faces has an evolutionary advantage for social beings).
Steps:
1. Infants (7-months) are
presented with a pairs of
stimuli (i.e., blue square or
clue and white check square)
2. Researchers are interested
in whether infants are able
to discriminate between the
two images which is implied
if they spend a significantly
longer time looking a one
screen than the other.
3. Compares looking time of
two images that are
presented side by side.
Problem: o How do we interpret no difference findings? When infants show no visual preference for one image over the other? Is it that infants are not able to discriminate between the two images or that they can but do not have a preference between them?
(2) Habituation Technique
Addresses this problem
Steps:
1. Habituation Trial:
Where infants are
repetitively presented with a
single stimuli (circle) until
they no longer react to it (i.e.,
familiarised, habituated to,
bored).
2. Dishabituation Trial:
A novel stimuli is presented
(cross).
3. Test Trial:
If there is recovery of
attention (increase in
looking time) to new
stimulus, then indicates
discrimination between
old/familiar and new stimuli.
Logic:
Researchers are interested
to see if the infants attention
is caught by the novel stimuli
and they spend more time
looking at the new stimuli.
This indicates they are able
to discriminate between the
two images (old/familiar and
new stimuli).
This is its advantage over
method 1.
(3) You can combine method 1
& 2
habituation technique with
preference technique
Slater et al. (1983)
Steps:
1. Learning Phase:
2. Use habituation technique
to familiarise infants to a
particular stimulus (circle)
3. Test Phase:
4. Adopt a preference
technique by presenting
them with an old and new
stimulus side by side to see
which one they spend more
time looking at.
Logic: If they’re able to remember which item they’ve seen before and discriminate between the two images, then they should show a preference for looking at the novel stimuli. Results: Slater confirmed that even newborn babies can discriminate between old/new stimuli and demonstrate a visual preference for novel stimuli. We can conclude that the absence of a preference in seven-month-old infants in Fantz’s experiments did not arise out of an inability to distinguish between crosses and circles
Important Distinction about Visual Discrimination Tasks (1-3)
o The Habituation Method and the Visual Preference technique were historically designed to study infants “basic visual discrimination”. o Although these techniques were historically used to suggest that infants visually see the world in a non- random fashion, in recent years, some scientists have ventured further to boldly claim that the technique could be used to show babies have abstract cognitive understandings of the world around them.
What is cross-modal perception?
Cross-Modal Perception
The ability to match perceptual information across modalities (cross-modal perception) also appears to be present from early in life. Infants seem to be able to connect visual information with tactile information, and auditory information with visual information, from soon after birth
Can infants match and weight perceptual information across different modalities? Coordinate sensory information in our physical world?
Visual & Tactile
Meltzoff & Borton (1979)
Meltzoff & Borton (1979)
Steps: 1. Infants were either asked to suck on a pacifier with a smooth or rough surface (textile) 2. The pacifier was removed, and they were then presented with two images of the rough and smooth surfaced pacifier (visual). 3. Researchers were interested in what image the infant showed a preference to look at; will they be able to integrate the textile and visual information on the pacifier they have to look longer at the image of the pacifier they were sucking on?
Results: Studies show 29-day-old infants look longer at the shape that matched the one they tactually explored in their mouths (preference for visual image that matched the texture of the pacifier they had experience with).
Implications: This suggests that ability to make cross-modal connections between oral touch and vision develops very early (29-day old infants can coordinate visual and oral sensory information. Suggests an early understanding of cross- modal equivalence.
What about visual and auditory information? Can infants coordinate this cross-modal information? How would we test this?
Hyde et al. (2013)
Hyde et al. (2013) Using electrophysiological (EEG) Study they showed infants can match sight and sound information.
Steps: 1. Habituation phase: - 5-month-old infants were familiarized (habituated) to pairs of sights and sounds (e.g., short caterpillar with a shot beep sound or a long caterpillar with a longer tone = Congruent). 2. Note: The researchers made the task attention worthy by having the picture of the short and long caterpillar stay on the screen for 1000 - milliseconds – makes visual size as well as auditory information in the task distinct and relevant. 3. Test phase: - Infants were either shown the familiar congruent sound and visual information (short caterpillar with a shot beep sound or a long caterpillar with a longer tone = congruent) or an incongruent pairing (incongruent= short caterpillar with long tone or long caterpillar with short tone) to see which information would the infants prefer to look at?
Results: EEG results show that there is greater amplitude (activity) towards the familiar congruent pairing relative to the incongruent pairing. In contrast, young infants familiarized to incongruent pairings (short-long/long- short) showed no differences in early processing or attentional orienting between congruent and incongruent pairings in the test phase.
Implications: Means there is enhancement of attention to and remembering of information where there is match between sight and sound (cross-modal congruent information).
But does that also mean infants cannot detect when there is mismatch between sight and sound at all? Do infants only focus on congruent information?
(Srinivasan & Carey, 2010)
Of course, infants can detect incongruence in information across different modalities.
(Srinivasan & Carey, 2010)
Steps: 1. 9-month-olds after familiarized to congruent pairings of sight and sound (long-long, short-short). 2. Infants are tested on whether they pay more attention to incongruent or congruent pairings.
Results: Older infants show a novelty preference where they pay more attention to and look longer at incongruent pairings than congruent pairings.
Implications: Younger infants may show enhanced attention to when vision and audition are linked (congruent) which is good for learning about stabilities in the world. As infants get older, they perhaps start to pay more attention to unusual (incongruent) pairings of information.
Can discriminate visually. Can we use habituation methods to study whether infants can realise visually distinct objects belong to the same category? Group information on distinctive objects into abstract categories? Higher level categories.
Slater & Morrison (1987)
Yes we can – by varying the stimuli that infants observe during the habituation phase. Here are three examples of research studies that have done so.
(1) Slater & Morrison (1987)
Steps: 1. Habituate infants to a series of different patterned circles (3- to 5-months). 2. Test how infants react to a new circle they haven’t seen before and another novel shape. Which one will they look at longer?
Results:
Infants looked at the novel
shape longer (dishabituation).
Implications: Suggests that infants formed a “prototype” of the shape (“circle”) during habituation to which they compared subsequent stimuli. Novelty preference where new stimuli that is incongruent with the developed higher order category are looked at longer.
*distinct objects can be a part
of the same category.
(2) Cohen & Caputo (1978)
Use the same technique where researchers varied the stimuli that infants observe during the habituation phase to see how infants consolidate knowledge.
Steps:
1. 7-month-old infants were
split into three groups in the
habituation phase:
a. Habituated to the same
single stimulus (stuffed toy)
b. Habituated to changing
stimuli (different animal
stuffed toys)
c. Habituated to unrelated
objects (cat, car, ball etc.)
2. How do infants in these two
groups treat this
information? Will they class
distinct object into one
category? Researchers
tested this by comparing
looking time across two
stimuli to see if they
demonstrate a visual
preference between a toy
skunk and a rattle.
- Test: Compare visual
preference when novel
stimuli are presented
(stuffed skunk or rattle)
Results: • Infants in ‘Changing Animal’ Group found the skunk “familiar” (look less) & looked longer at the rattle = abstract category formed. • Infants in the ‘Same Animal’ group found both items interesting and showed no visual preference = no category formed. • Infants in the ‘Objects’ group found both items interesting and showed no visual preference = no category formed.
(3) Younger (1985)
Helps address questions from example 2. A stronger demonstration that infants can code correlational structure between features across the stimuli! repetitions across stimuli.
Steps:
1. 10-month-olds allocated into
either Broad Condition or
Narrow Condition.
- They were familiarized
(habituated) with different
pictures of creatures where
the neck (long/short) and leg
size (long/short) varied
(patterns or correlations
between stimuli structure
change).
3. Broad condition showed lots
of variation in leg and neck
length which were mixed
and matched apart from
value (3). They never saw
animal with leg/neck length
of three (i.e., the average
value in length). Narrow
condition only saw biggest
or smallest value of neck
and leg (1-5) only two
variations!
4. Test phase (1 & 2) Will infants
look longer at animal with
average neck and leg length
or the animal with the
extreme neck and leg
values?
Results: Infants in broad condition preferred to look at extreme looking creatures (1-5). Infants in the narrow condition preferred to look at the average creature (3-3).
Explanation of Results: Infants in the broad condition were exposed to a variety of neck/leg lengths but size 3 (1- 2-4-5). They grouped this information by creating an/singular average category with the values (3-3) therefore when they were presented with an average and extreme looking creature in the test phase they preferred to look at the extreme creature. Novelty preference for the extreme preference. Infants in the narrow condition were exposed to extreme creatures and created two extreme categories of creatures (1-5; 5-1) therefore they found they showed a novelty preference for the average looking creature.
Implications: Infants are not passively absorbing information they pick up on correlations between the features of the stimuli they encounter.
*three authors show that infants can perceive that visually distinct objects belong to the same category and can code correlational structure between features across stimuli.
Implications: This suggests that Group Two (changing) formed category of “stuffed animals” from Habituation Phase. Infants cognitively analyse the visual information in their physical world and search for patterns or similar features of distinctive objects to form abstract categories to help making learning new information easier. Bold claim. Are we confident that infants are using statistical learning to do this? Are infants actually processing different features (e.g., legs and neck, or legs and eyes) of each animal, rather than merely habituating to a single recurring feature (e.g., legs). In real world, features can co- occur so is there research showing infants can detect correlations between certain features?
How are infants able to do this? and how do their perception skills progress so rapidly?
Through statistical learning (Saffran et al., 1996)
Attending to distributions and regularities in visual (or auditory) input to learn which features occur together. Statistical learning helps infants discriminate features in stimuli that occur together from features in stimuli that seldom occur together.
For example, babies would show more attention to syllables ty-ba because through experience and statistical learning they know these syllables are 0.02% likely to follow one another relative to pre-tey is 80% likely to follow one another (i.e., conditional probability).
Why is it important to appreciate studies that show infants can attend to and remember visual details and can group details to form or remember larger events and higher order categories?
Too much attention to small details (instead of the general bigger picture) can also be a liability (though can also lead to islets of abilities). For example, one important characteristic of autism spectrum disorders is enhanced attention to details but have weakness in noticing the global picture. Individuals with autism especially good at picking out hidden shapes in pictures, and gazing at the stand-out letter in a pattern Individuals with autism are more error prone at going beyond local details to interpret the global picture (seeing letter S instead of fixating at the little letter H) Understanding how attention and perception develops typically and how it is measured can help us understand and support people with autism (i.e., they would see the letter H and not pick up that they collectively form the letter s). Compare typical with atypical development to help design treatments for autism.
Perceptual structure is measured in three main facets:
1. Spatial relations (i.e., X is taller than Y) 2. Occlusion relations (i.e., X is out of view & covered by Y) 3. Support relation (i.e., X is resting on Y)
Is there research to show infants have understandings, knowledge or expectations of perceptual structure in the visual world, and how do we test it?
It’s uses blank and blank techniques
It test the blank concept
- Use violation of expectation
paradigms. - If infants have such
expectations, we can
introduce violations of these
expectations and measure
behavioural responses (i.e.,
looking time) to the
violations.
What is a violation of expectation paradigm?
- The Object Concept
- It is a technique for figuring
out infants’ cognitive
understandings of the world.
It uses habituation
(familiarised to form a rule or
expectation of how the
object is expected to work)
and dishabituation
procedures (rule violation)
whereby an infant’s
dishabituation reaction (e.g.,
increased looking behaviour)
to an unexpected event is
used to infer that the infant
knows about the laws that
govern how such events
ought to work. - The object concept: One
core aspect to understanding
structure of perceptual world
is that objects continue to
exist when hidden. - The violation to expectation
paradigm is well known for
testing the object concept in
young infants. We always
need to consider piagets
theory that infants are
believed to hold NO
representations of objects in
infancy (up to 18 months, only
after this can they create
symbolic representations of
objects) and therefore when
object is out of sight it
doesn’t exist. Thus, work in
this area which disproves this
is very important for adding
to theory on infants’
perception. - We can use the VOE
paradigm to find out if infants
understand spatial and
occlusion relationships and
in so doing show that infants
understand object
permanence (object
concept)!
Do infants represent spatial relations?
Using VOE paradigm-
Baillargeon & Graber (1987)
Baillargeon & Graber (1987)
Steps: 1. Habituation Phase: - Infants (5 ½ month old infants) are familiarized to the video of a short and tall carrot going behind a wall where it is can not be seen till it comes out the other side till habituation is reached. 2. Test Phase: - They compare looking time between expected and unexpected event phase. In the test phase the wall is shorter in the middle an expected event is when the short carrot goes behind the wall and is occluded to us (i.e., expected because the carrot is shorter than the wall). An unexpected event is when the tall carrot goes behind the wall and we do not see the top of the carrot as it goes behind the short wall (i.e., unexpected because the carrot is taller than the height of the wall, so we expect to see it).
Logic: - If infants truly understand spatial relations about height of the object in relation to other objects (wall) in the physical world than infants should pay more attention to violation to expectations (impossible events) relative to possible events.
Results: - Research shows infants look reliably longer at the impossible tall-carrot event than at the possible short- carrot event
Implications
- The Results implies that
infants develop expectations
about:
(a) each carrot continued to
exist behind the screen
(object concept),
(b) each carrot retained its
height behind the screen
(remember and use spatial
relational information to
build expectancies about
objects in their physical
world),
(c) each carrot pursued its
trajectory behind the screen
(trajectory continues even if
object is out of sight),
(d) the tall carrot to appear in
the screen window and
were “surprised” that it did
not (longer looking time at
impossible event implies
they built expectations
about the object and were
surprised when it did not
follow the expected pattern).
*infants represent spatial relationships and disprove paigets theory by showing young infants have an understanding that objects exist out of sight and they retain their physical properties when hidden and expect objects to behave in accordance to their physical properties (i.e., height).
Study 2:
If we accept that 5 ½ month infants are cognitively reasoning about spatial relationships, develop expectancies on how objects will behave in relation to their environment based on the physical properties they hold, then if we reveal the trick to them than they should no longer be surprised by the impossible event (second study by the same authors tested this).
Steps: - Before Habituation - Infants were shown one of two events: you show infants two short carrots or two tall carrots standing motionless on either side of the windowless screen (reveal secret behind the trick, so to speak; that there were two objects present and explain why you didn’t see the top of the tall carrots head when it “passes” behind the short wall), and then run the standard habituation and test phases – the effect goes away. Infants now no longer find the tall-carrot event at test “surprising” (no difference in looking time across short/tall events). - This suggests that infants may be using information about two carrots to make sense of the events, and that infants capable of relatively sophisticated reasoning about the physical world (i.e., object permeance at a very young age).
Do infants represent occlusion relations?
Second type of evidence of infant’s ability to understand object permeance is to look at occlusion studies-
Baillargeon (1987)
Drawbridge Study
Baillargeon (1987)
Drawbridge Study
Steps: 1. Habituation: - 3.5- to 4.5-month-old infants were habituated to a drawbridge which moved from 0-180 degrees. 2. Test: - Then compare looking times to impossible event (there is a wooden block place in the path of the drawbridge, yet it still goes from 0-degress to 180-degrees; two objects can not occupy the same space or pass through one another) versus a possible event (the wooden block stops the screen from at about 112- degrees).
Results: - Babies in impossible condition (dishabituation) looked longer than babies in possible condition. - Very young infants understand object permanence; they represent the box as continuing to exist, even when hidden by screen! and understand that it would block the path of the drawbridge and cause it to stop at 112 degrees when they make contact.
Implications: - Paying more attention to impossible event supports that young preverbal infants understand that objects continue to exist out of sight and should block its path.
Criticisms of the Drawbridge study?
Does it really show infants understand object permeance?
*Remember that habituation and dishabituation tasks with preferential looking times were
originally designed to answer rudimentary basic level questions about infants’ perceptual abilities (i.e., discrimination) as opposed to more ambitious questions about cognitive reasoning.
The Debate:
1. Interpretation:
Infants understand object permanence in an abstract sense!!
- Interpretation:
Infants merely continue to see the box even once it is occluded due to a kind of lingering visual memory trace which is in their minds’ eye; and consequently, infants look longer at the “impossible” event not because it violates rules of physics but because of the perceptual novelty of seeing one object pass through another object.
What do we mean when we say lingering visual memory traces?
In vision, lingering visual memory traces are easy to demonstrate – like bird in cage visual impression. So, in the Drawbridge case, it’s just like infants continuing to “see” the drawbridge pass through the box which is perceptually interesting. But the results may have little to do with cognition of object permanence.
Video of bird cage and bird on opposite sides of a piece of paper that when it is spun quickly it looks like the bird is in the bird cage. This is because the image of the birdcage lingers in the brain for a couple of milliseconds after the image is removed from out field of vision. Thus, when we are shown the image of the bird it appears to be inside the birdcage (fuse two images together to make sense of the world).
In their minds eye they are seeing the block and is fused with current image of the draw bridge completing its 180 turn and thus to them looks like it is going through the object. Thus, they’re believed to be responding to this novel image and not cognitively reasoning about how the physical characteristics of the block, that continues to exist when out of sight, should block the path of the drawbridge (i.e., violation of expectation).
How do we support the claim that infants are developing abstract senses of occlusion relationships?
Steps: - Infants see a large cube placed on top of the path. A screen covers the cube, and a car rolls down. [But the block is secretly removed so that its out of the way.] The car rolls down and “magically” the car appears on the other side of the path seemingly unaffected by the block (i.e., the block should have obstructed its path and stopped its motion; perceived that the car somehow went through the block). 6-months olds’ are surprised by this event (impossible event) and look for a long time at such impossible events.
Findings: - The findings suggest infants understood the block’s permanent existence behind the screen even if they couldn’t see it. Additionally, they understood that the rolling car couldn’t pass throughout the block (i.e., due to their physical properties it should stop the car in its motion because they cannot go through each other), suggesting that infants understand object permanence.
Implications: - This provides additional evidence on infant's concept of object permeance in a different scenario of an occlusion event.
Another way to support infants’ ability to understand object permeance is to look at their brain activity (neurological markers) during impossible events in a violation to expectation task.
Kaufman et al. (2003)
Kaufman et al. (2003) - blending Looking Time & Cognitive Neuroscience approach to showcase infants’ understanding of occlusion relations (object permanence)
Steps: - Compared looking time when infants (6-month-old) observed an expected object disappearance event with an unexpected object disappearance event. - In the expected condition a toy train would go through a tunnel and out the of the room and they see a hand reach down to pick up the train but is no longer there. - In the unexpected condition the toy train goes into the tunnel, and not out the other side, so when the hand reaches down to take the train out of the tunnel, we are shocked to see it isn’t there, the hand puts the tunnel back down and the train come out of the tunnel).
Results: - Infants pay more attention (longer looking time) at the unexpected disappearance event relative to the expected disappearance event. - EEG shows increase in right- temporal brain activity; seems infants’ brains attempting to maintain representation of object’s existence in the face of contradictory visual input (brain activity coincided with the moment that the hand lifted up the tunnel and showed the train was unexpectedly gone).
Implications: - The EEG results supports that infants put hard cognitive work to maintain their cognitive processes and engage in cognitive reasoning when violations to expectations occur to understand why it happened. - Converging evidence adds additional support for their object permeance understanding in early infancy.
*This does not mean that they
understand everything about
the perceptual structure of
objects in our physical world or understand everything on the permeance of objects. For example, we do not know yet if infants understanding of disappearing objects extends to the appearance of objects!
Study 2: - They conducted a second study which compares looking time between expected appearance of objects and unexpected appearance of an object. - In the expected appearance event the toy train goes into the tunnel and the tunnel is lifted to reveal the train the tunnel is placed back down and the train comes out of the tunnel. In the unexpected appearance conditions, the toy train enters the tunnel and comes out the other side, then a hand lifts up the tunnel to reveal a train (we saw the tunnel leave the room why is it still in the tunnel).
- Results:
- indicate that young infants
showed no statistical
difference in looking time
between expected and
unexpected object
appearance conditions. No
object permeance skill on
object disappearance not on
appearances, this skills is
developed later on in life
when they have more
experience to these events. - Implications:
- Overall, research suggests
that infants DO have an
understanding of object
permanence, and this
understanding covers object
disappearances from early in
life, and then perhaps very
much later infants will start to
understand object
appearances.
Now we may ask do infants understand relationship between object contact and the level of support it gives objects?
Baillargeon, Needham & De Vos (1992)
Baillargeon, Needham & De Vos (1992)
Steps: 1. Infants were shown a 15% contact event and a 100% contact event. In the 15% contact event, they see a hand push a box to along a table till only 15% of the bottom of the object is in contact with the table and yet it remains to be stable and not fall off the edge. In the 100% contact event infants see a hand push the box along the table’s edge but 100% of the object stays in contact with the table. 2. They compare looking times between the 15% (unexpected) and 100% (expected) condition to see if they understand the need for the object to be supported in order to stay up on the table.
Results: - Older infants (from 6.5- months of age) looked longer at the 15% contact event relative to the 100% contact event showing that they have support relationship understandings. - Then using the same method these infants were shown a 15% contact and a 75% contact event (percentage of the bottom on the box in contact with the top of the table). Adults can understand that 75% contact gives sufficient support to keep the object stable but 15% is insufficient and gravity will cause the object to fall. If infants understand this they will look longer at the 15% event relative to the 75% event, and there is no difference between 75-100% events.
Results:
Results support this: Older infants (from 6.5-months of age) appreciate how much support (e.g., 75% versus 15% contact between surfaces) must be available for objects to be stable and supported.
BUT younger infants (e.g., 3-month-olds) fail to understand amount of contact.
Young infants (e.g., 3-months of age) expect box to fall when pushed completely off platform and to remain stable otherwise; any amount of contact between top and lower box is considered sufficient to ensure stability. (3-mth-olds will look longer at 0% contact compared to 100% contact) (but 3-mth-olds show no difference in looking times between 15% and 100% contact)
Contact = support (do not have a sophisticated understanding yet)
Experience is needed for infants to develop understanding of the AMOUNT of contact needed for an object to be supported!
Basic understandings of object permeance, with the three methods, appears to be innate but sophisticated understandings require experiential learning that older infants have.
Why is it important to know that infants have core principles about the world and are sensitive to violations of expectations?
If infants are particularly sensitive to VOE it also means they are more likely to benefit from these responses. Focusing on events that VOE provide excellent opportunities for learning
Stahl & Feigenson (2015)
Stahl & Feigenson (2015)
Steps: - Are shown a support or solidity event: - In the support event the toy car was pushed to the edge of the track, and it ever falls onto the floor (expected) or floats on the air without support (impossible). In the solidity event, the car was pushed along the track and hits a barrier and stops their (expected) or it hits the barrier and continues to go through it (impossible). – violation to principle of support and solidity. - Habituated to expected than dishabituated to impossible event/knowledge violation scenario.
Results: - 11-month-old infants selectively explore objects in ways specific to the violation observed; they bang objects that violate expectations of solidity and drop objects that violate expectations of support. - “Infants look longer at surprising events suggest not only that infants are equipped with core knowledge about fundamental aspects of the world and that this knowledge is harnessed (they use the knowledge and test objects that violate our expectations) to empower new learning even in infancy.” (Stahl & Feigenson, 2015)
Key Point: - infants who observed the unexpected event were more likely to interact with that object than when it took the expected path. This provides novel evidence that infants pay more attention to and want to interact with things that violate their understanding of the world to figure out why it didn’t follow their expectations and learn from it. - This is why its important to provide babies with diverse stimulating experiences to get them to push their understanding, interact with objects in their environment and create more sophisticated cognitive representations of objects that they can use to further their learning and memory.
Summary Points:
It was not long ago (1970s) that Paigets developmental theory where he viewed infants feel it as one great blooming, buzzing confusion. Assailed by their senses and there was not structure to their perception or thinking. Within 50 years of developmental research, we know they have organised memory, attention systems, visual discrimination ability and perceptual structure demonstrate they have an organised mind (four strands of research which support this; memory, attention, visual discrimination and perceptual structure).
Working Memory Span study shows that the development of the prefrontal cortex aids the development of their working memory span from five to 12 months of age.
Adults and infants have similar working memory systems; changes to stimuli and contextual factors impairs their explicit long-term memory indicating it has capacity limits and is context specific like adults. Without language skills it is hard to undoubtedly confirm they’re consciously accessing this information but we can use converging information from mobile and deferred-imitation tasks to build a convincing argument
Important to notice that 6-month old infants were able to remember information about their physical world for up to 2 weeks but in the deferred-imitation task it was only up to a day. This is because infants took a more practical approach to learning in the mobile task and interacted with the objects whereas in the puppet study they passively watched the researcher interact with the puppets.
The mobile task is an example of how infants can develop associations between objects (cause-effect relationships) and the differed-imitation task is an example of how infants are able to connect multiple associations together or apply a learnt association onto equivalent stimuli.
When the mobile task and the differed-imitation task methods are combined a spreading of activation allows for the recall timeframe to extend from 1 day to up to 2 weeks (repetition of task could also extend this window).
Infants Attention is structured, focused and operates like adults.
Visual Discrimination Tasks are used to test whether infants can distinguish between novel and old stimuli. An important skill for attention. Two techniques to measure this; visual preference technique (uses 2 screens) and habituation technique (uses to screens) (or combination uses one screen).
Caveat of visual preference tasks is that it is hard to draw conclusions from no difference in looking time results. Is the infant equally excited, equally bored of both stimuli or not able to distinguish between them?
These tasks show that infants are able to develop higher order categories about stimuli in their environment through the use of statistical learning (automatic process of noticing patterns between stimuli and categorising this information into a cognitive framework).
To be able to live in a world full of information from our five senses we need to be able to integrate information across modalities.
Why do younger infants prefer congruent cross-modal information than novelty or incongruent information? This is because when they’re young they want to be able to perceive the world as structured, ordered and stable. From 10-months we see that infants develop a novelty bias and begin to prefer incongruent cross-modal stimuli (i.e., caterpillar study).
Statistical Learning is an automatic process developed in young infancy which allows us to identify patterns within their physical world, build expectations about how objects should behave to structure their attentional systems and develop abstract categories that ultimately aid their development.
Sophisticated visual analysis is evident but are they thinking (cognitive) when they perform this analysis? Use VOE paradigms, perceptual structure.
Three example studies; 1) the carrot study tested spatial relations about the height of the objects; 2) the box on a table study tests their reactions to support/contact relations ; 3) train in a tunnel study to test their reactions to disappearances and appearances of objects (occlusion).
The drawbridge study is another occlusion study that tests whether infants have object permeance (the understanding that objects exist when hidden). It demonstrates that infants have a sophisticated cognitive understanding of their physical world; they understand the physical properties of object (coexist in same place or time, go through one another or that they continue to exist when hidden).
The debate on whether the drawbridge study shows cognitive reasoning or if its due to a lingering memory trace or they merely like the movement more (180 > 120).
We impose meaning in our interactions with our physical world and not assailed by information from our four senses. We learned about the different kinds of studies and their methods and findings to show that even pre-linguistic infants lead cognitively meaningful lives, so much so that infants capable of remembering, attention, visual discriminations. They even expect structure in the physical world.
