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Transcript
Seeing, Thinking,
and Doing in Infancy
How Children Develop (3rd ed.)
Siegler, DeLoache & Eisenberg
Chapter 5
Guiding Questions
1.
How do infants perceive the world around them?
2.
What capabilities do infants possess?
3.
What major milestones occur during infant development
and how does the environment influence the
development of these milestones?
4.
What have classic research studies taught us about the
perceptual and cognitive abilities of infants?
How do infants
perceive the world
around them?
A. Vision
B. Auditory Perception
C. Taste and Smell
D. Touch
Perception

Sensation: refers to the processing
of basic information from the external
world by the sensory receptors in the
sense organs and brain

Perception: the process of
organizing and interpreting sensory
information about
the objects, events,
and spatial layout
of our surrounding
world
Visual Capabilities at Birth

Research methods for studying infants’ vision:

Preferential-looking technique: involves showing
infants two patterns or two objects at a time to see if
the infants have a preference for one over the other

Habituation: involves repeatedly presenting an infant
with a given stimulus until the response declines

If the infant’s response increases when a novel stimulus is
presented, the researcher infers that the baby can discriminate
between the old and new stimuli.
Visual Acuity


The sharpness of infants’ visual discrimination
develops so rapidly that it approaches that of
adults by age 8 months and reaches full adult
acuity by 6 years of age.
An infant’s visual acuity can be estimated by
comparing how long the
baby looks at a striped
pattern such as this one
versus a plain gray
square of the same size
and overall brightness.
Visual Acuity

Young infants prefer to look at patterns of
high visual contrast because they have poor
contrast sensitivity (the ability to detect
differences in light and dark areas).


This is because the cones (light-sensitive neurons)
of the eye, which are concentrated in the fovea, differ
from adults’ in size, shape, and spacing.
In addition, very young infants have limited
color vision, although by 2-3 months of age
their color vision is similar to that of adults’.
Visual Scanning

Scanning
 One-month-olds (a)
scan the perimeters
of shapes.
 Two-month-olds (b)
scan both the
perimeters and the
interiors of shapes.

Tracking
 Although infants begin scanning the environment
right away, they cannot track even slowly moving
objects smoothly until 2 to 3 months of age.
Faces

From birth, infants are drawn to faces because
of a general bias toward configurations with
more elements in the upper half than in the
lower half.

From paying attention to real faces, the infant
comes to recognize and prefer his or her own
mother’s face after about only 12 cumulative
hours of exposure.
Faces

With experience, infants not only
develop a preference for the type
of face they see most often, but
also come to understand the
significance of different facial
expressions.

From birth onward, infants look
longer at faces that adults find
more attractive than those adults
rate as less attractive, and interact
more positively with people with
attractive faces.
Same or Different?

As an adult human,
you no doubt can
tell the two men
apart quite easily,
but you may still not
be sure whether the
two monkey photos
are of different
individuals or not.
Pattern Perception

Two-month-old infants can analyze and
integrate separate elements of a visual
display into a coherent pattern.



When you look at this figure, you
no doubt see a square—what is
called a subjective contour,
because it does not actually exist.
Seven-month-olds also see the
overall pattern here and detect the illusory square.
Infants are also able to perceive coherence
among moving elements.
Object Perception

Perceptual constancy is
the perception of
objects as being of
constant size, shape,
color, etc., in spite of
physical differences in
the retinal image of the
object.

If an infant looks at the
larger, but farther-away
cube, researchers will
conclude the child has size
constancy.

Supporting the nativist
position, visual
experience does not
seem to be necessary
for perceptual
constancy.
Object Segregation




Infants who see the display in figure
(a) perceive it as two separate
objects, a rod moving behind a block.
After habituating to the display, they
look longer at two rod segments than
at a single rod (b), indicating that
they find the single rod familiar but
the two segments novel.
If they first see a display with no
movement, they look equally long at
the two test displays.
This result reveals the importance of
movement for object segregation.
Object Segregation

The identification of separate
objects in a visual array




Two-month-old infants use common
movement to perceive object
segregation.
Older infants, like adults, use additional
sources of information for object
segregation, including their general
knowledge about the world.
In figure (a), for example, it is
impossible to know for sure whether
what you see here is one object or two.
Because of your knowledge about
gravity and support, you can be sure
that figure (b) is a single, albeit very
odd, object.
Depth Perception

Infants as young as 1 month respond to optical
expansion, a depth cue in which an object occludes
increasingly more of the background, indicating that
the object is approaching.

Stereopsis, the process by which the visual cortex
combines the differing neural signals caused by
binocular disparity (the slightly different signals sent
to the brain by the two eyes), emerges suddenly at
around 4 months of age.
Depth Perception

At about 6–7 months
of age, infants
become sensitive to a
variety of
monocular or pictorial
cues, the perceptual
cues of depth that can
be achieved by one
eye alone.

These include
relative size and
interposition
Depth Perception

This 7-month-old infant is using the
monocular depth cue of relative size.


Wearing an eye patch to take away binocular depth
information, he is reaching to the longer side of a
trapezoidal window.
This behavior
indicates that the
baby sees it as
the nearer, and
hence more
readily reachable,
side of a regular
window.
Pictorial Representations

Despite the fact that even
newborns can recognize
two-dimensional versions of
three-dimensional objects,
children must come to
understand their symbolic
nature.

Before they reach about 19
months of age and have
substantial experience with
pictures, infants and
toddlers attempt to treat
pictures as though they were
real objects.
B. Auditory Perception

Although the human auditory system is
relatively well developed at birth, hearing
does not approach adult levels until age 5
or 6.

Infants are remarkably proficient in perceiving
subtle differences in human speech.
Auditory Capabilities at Birth

Newborns turn toward sounds, a phenomenon
referred to as auditory localization.
Music Perception

Recent research evidence
suggests a biological foundation
for music perception.


Infants share the strong preferences
adults have for some musical sounds
over others.
Infants also respond to rhythm in music
and are sensitive to melody, showing
habituation to the same tune regardless
of pitch.
C. Taste and Smell

Sensitivity to taste and smell develops
before birth.

Newborns have an innate preference for
sweet flavors.

Newborns prefer the smell of breast milk and
by two weeks of age appear to be able to
differentiate the scent of their own mothers
from that of other women.
D. Touch

Infants learn about the
environment through
active touch.


Oral exploration
dominates for the first few
months.
Around 4 months of age,
infants gain greater control
over their hand and arm
movements, and manual
exploration gradually
takes precedence over
oral exploration.
Vital Role of Touch for Infants
What capabilities do
infants possess?
A. Perceptual Capabilities
B. Reflexes
A. Perceptual Capabilities






Sight
Hearing
Taste
Smell
Touch
Intermodal perception
Intermodal Perception

The combining of information from two or
more senses is present from very early in
life.

Very young infants link sight and sound,
oral and visual experience, and visual and
tactile experience.

When two videos are presented simultaneously, 4month-old infants prefer to watch the images that
correspond to the sounds they are hearing.

Using a similar technique, researchers have found
that by 5 months of age, infants associate facial
expressions with emotion in voices.
Research Technique for
Intermodal Perception



A set-up like this one enables researchers to
study auditory–visual intermodal perception.
The two computer
screens display
different films, one of
which is coordinated
with a soundtrack.
The video camera
records the infant’s
looking toward the
two screens.
B. Reflexes


Newborns demonstrate
reflexes – innate, fixed
patterns of action that
occur in response to
particular stimulation.
Some reflexes, such as
rooting and sucking, have
clear adaptive value

Others, such as the tonic neck
reflex, have no known
adaptive significance.
Examples of Newborn
Reflexes
What major milestones occur
during infant development?
How does the environment
influence the development of these
milestones?
Motor Milestones
Impact of Culture on Motor Development

Mothers in Mali believe
it is important to
exercise their infants to
promote their physical
and motor development.

The maneuvers shown
here do not harm the
babies and do hasten
their early motor skills
Current Views on Motor Development

Previously believed to be an element of
neurological maturity

Current theories, however, often take a
dynamic-systems approach, emphasizing a
confluence of many factors, including not
only neural mechanisms but also increases
in strength, posture control, balance,
perceptual skills, and motivation.
Illustrating the
Dynamic Systems View

Research by Esther Thelen
and colleagues examined the
stepping reflex, the infant’s
performance of stepping
movements when he or she is
held under the arms with feet
touching a surface.

The reflex was thought to
disappear at about 2 months
of age because of cortical
maturation, but
demonstrations that the reflex
could be prolonged or elicited
long after it was scheduled to
disappear were inconsistent
with this interpretation.
Illustrating the
Dynamic Systems View

Thelen performed two experiments to test the
hypothesis that rapid increases in infants’ weight
made it impossible for them to execute stepping
motions.



In one experiment, weights were attached to the ankles of
infants who still had the stepping reflex, and the babies
suddenly stopped stepping.
In the second study, infants who no longer showed the stepping
reflex were found to do so when they were suspended waistdeep in a tank of water that supported their weight.
Hence, the movement pattern and its neural basis
remains but is masked by the changing ratio of leg
weight to strength.
Reaching

For the first few months, infants are limited
to prereaching movements – clumsy swiping
movements by young infants toward the
general vicinity of objects they see.

Infants begin successfully reaching for
objects at around 3 to 4 months of age.
Reaching

At about 7 months, as
infants gain the ability to
sit independently, their
reaching becomes quite
stable.

Reaching shows signs of
anticipation, and by 10
months of age, infants’
approach to an object is
affected by what they
intend to do with the
object.
Self-Locomotion

At around 8 months of age,
infants become capable of selflocomotion for the first time as
they begin to crawl.

Infants begin walking
independently at around 11 to
12 months of age, using a
toddling gait.
Back-Lying and Locomotion

The campaign to get parents to put babies to
sleep on their backs to reduce the risk of SIDS
seems to make infants less likely to roll over on
schedule.



It may be that the better view of the world from their backs
results in less motivation to roll over.
It may also be that spending less time on their tummies
causes arm strength to develop more slowly.
The research is reassuring in that by 18 months
of age there were no differences in the
development of infant crawling.
What have classic
research studies
taught us?
What have they taught us about
infant perception?
Visual Cliff Research

Research with the visual cliff illustrates the
interdependence of different domains of development.

Using the visual cliff, Gibson and Walk found that 6- to
14-month-old infants perceived and understood the
significance of the depth cue of relative size.

Subsequent work by Campos and his colleagues using
heart rate deceleration as the dependent measure
indicated that infants could perceive the difference in
depth but showed no fear of the deep side.

In a series of studies, the researchers found that the
experience of moving themselves around in the
environment plays a very important role in babies’
developing understanding of the significance of
differences in the height of surfaces.
Visual Cliff Research

Social referencing, the use of
another’s emotional reaction to
interpret an ambiguous situation,
appears to be important in infants’
development of wariness of heights

Thus, development in one domain
clearly influences development in
other domains.
Adolph’s Research

Karen Adolph and her colleagues have found
that infants do not transfer what they learned
about crawling down slopes to walking down
them.
Scale Errors


Toddlers also make scale errors, in that they try to do
something with a miniature replica object that is much
too small for the action to be completed.
One little boy is perched on top of a miniature chair,
trying to sit in it just like he did with a similar-looking
real chair, and the other is attempting in vain to get
into a tiny car.
What have classic
research studies
taught us?
What have they taught us about
infant learning and cognition?
Habituation Studies

A decrease in responsiveness to repeated
stimulation reveals that learning has
occurred.


The infant has a memory representation of the
repeated, now-familiar stimulus.
The speed with which an infant habituates is
believed to reflect the general efficiency of
the infant’s processing of information.

A substantial degree of continuity has been found
between these measures in infancy and general
cognitive ability later in life.
Habituation





This 3-month-old is seated in front of
a screen on which photographs are
displayed.
At the first appearance of a photo of
a face, her eyes widen and she
stares intently at it.
With three more presentations of the
same picture, her interest wanes
and a yawn appears.
By its fifth appearance, other things
are attracting the baby’s attention,
and by the sixth even her dress is
more interesting.
When a new face finally appears,
her interest in something novel is
evident.
Studies of Perceptual Learning

Infants actively search
for order and regularity
in the world around
them.

Differentiation is the
extraction from the
constantly changing
stimulation in the
environment of those
elements that are invariant
or stable.

A particularly important part
of perceptual learning is
the infant’s discovery of
affordances, the
possibilities for action
offered by objects and
situations.
Studies of Statistical Learning

Involves picking up information
from the environment, forming
associations among stimuli that
occur in a statistically predictable
pattern

From quite early on, infants are
sensitive to the regularity with
which one stimulus follows another.
Learning Through Classical
Conditioning

A form of learning that consists of
associating an initially neutral stimulus with
a stimulus that always evokes a reflexive
response

Plays a role in infants’ everyday learning
about the relations between environmental
events that have relevance for them

It is thought that many emotional responses are
initially learned through classical conditioning, as
demonstrated by the case of Little Albert.
Basic Components of
Classical Conditioning

Classical conditioning involves an unconditioned
stimulus (UCS) that reliably elicits a reflexive,
unlearned response – an unconditioned response
(UCR).

Learning or conditioning can occur if an initially
neutral stimulus, the conditioned stimulus (CS),
repeatedly occurs just before the unconditioned
stimulus.

Gradually, the originally reflexive response – the
learned or conditioned response (CR) – becomes
paired with the initially neutral stimulus.
Classical Conditioning
Gong
(UCS)
Crying
(UCR)
Associated
Similar
Animal
(CS)
Fear
(CR)
Learning Through Instrumental
Conditional

Also called operant conditioning

Involves learning the relation between one’s
own behavior and the consequences that result

Most instrumental conditioning research with
infants involves positive reinforcement, in
which a reward reliably follows a behavior and
increases the likelihood that the behavior will
be repeated.

There is a contingency relation between the infant’s
behavior and the reward.
Studying Instrumental
Conditioning in Infants
Contingency Relation
This young infant
learned within
minutes that
kicking her leg
would cause the
mobile to move in
an interesting
way.
Observational Learning

Infants as young as 6 to 9 months of age imitate some of the
novel actions they have witnessed.

The ability to imitate the behavior of others appears to be
present early in life, although in an extremely limited form.
 For example, newborns will stick out their tongues after watching
an adult model repeatedly perform this action.

In choosing to imitate a model, infants appear to pay
attention to the reason for the person’s behavior.
 Infants attempt to reproduce the behavior of other people, but not
of inanimate objects.

By 15 months of age, infants can imitate actions they have
seen an adult perform on television.
Imitating Intentions


When 18-month-olds see a person apparently try,
but fail, to pull the ends off a dumbbell, they imitate
pulling the ends off – the action the person intended
to do, not what the person actually did.
They do not imitate a mechanical device at all.
Infant Cognition



Object knowledge
Physical knowledge
Social knowledge
Cognitive Abilities





Research conducted over the past two decades has established
that infants’ cognitive abilities are much more impressive than
previously believed.
The extent to which these skills reflect nature versus nurture,
however, is a matter of debate.
Core-knowledge theorists maintain that infants are born with
some knowledge about the physical world.
Some theorists emphasize specialized learning mechanisms that
enable infants to acquire knowledge rapidly and efficiently in
some domains, whereas others emphasize general learning
mechanisms that gradually strengthen infants’ mental
representations of the world.
Still other theorists contend that perceptual-motor processes may
be responsible for much of what has been described as cognition
in infancy.
A. Object Knowledge

In contrast to Piaget’s description of the
development of object permanence, a great
deal of evidence now indicates that young
infants are in fact able to mentally represent
and think about the existence of invisible
objects and events.

The majority of the evidence is based on
research using the violation-of-expectancy
procedure, in which infants are shown an
event that should evoke surprise or interest
if it violates something that the infant
knows or assumes to be true.
Violation of Expectancy

Baillargeon and her
colleagues have used
this technique to
establish that infants
as young as 3½
months of age look
longer at an
“impossible” event
than at a possible
event.
B. Physical Knowledge

Knowledge of gravity begins in the
first year.


Infants have been shown to look longer at
objects that violate expected motion trajectories.
Infants also gradually come to
understand under what conditions one
object can support another.

This gradually refined understanding of support
relations is presumed to result from experience.
Developing Understanding
of Support Relations
C. Social Knowledge

Infants must acquire knowledge about people and their
behavior.



Distinguishing animate and inanimate entities
Knowing that the behavior of others is purposeful and goaldirected
By the end of their first year, infants have learned a great
deal about how people’s behavior is related to their goals
and intentions.

Suggesting very early precursors of theory of mind, 15-montholds can make inferences about what a person will do based on
the knowledge of what the person knows.
Understanding Intentions


Infants who see a human arm repeatedly reach for
an object in the same location assume that the
action is directed
toward the object,
not the place.
They looked longer
when the hand went
to the new object in
the old place, than
when it reached for
the old object it had
reached to before.
Understanding Intentions

Infants may attribute
intentions and goals to
inanimate entities as long
as they “behave” like humans.

In one study, 12- and
15-month-olds were
introduced to a faceless,
eyeless, brown blob that
“vocalized” and moved in response to what the infant or experimenter
did, thus simulating a normal human interaction.

Subsequently, when the blob turned in one direction, the infants
looked in that direction.

They did not behave this way with a blob whose behavior was not
contingently related to their own.
Attributing
Dispositional States

Twelve-month-olds also seem able, like adults, to attribute
dispositional states.

Infants watched a film that adults interpret as a ball “trying and
failing” to get up a hill as it is being “helped” by a triangle and
being “blocked” by a square.

Subsequently, with just
the three shapes on the
screen, infants looking
behavior indicated that
they expected the ball to
approach the helpful
triangle while avoiding
the hindering square.