Theories of Infant Development

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The First
Two Months
Fogel
Chapter 5
Created by Ilse DeKoeyer-Laros, Ph.D.
Overview Chapter 5
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Physical and Motor Development
Perceptual Development
Cognitive Development
Emotional Development
Family and Society
Experiential Exercises
Co-regulating with Baby
Physical and Motor Development
Newborn States
The fetal states of rest & activity develop into
sleeping & waking states
• at 32 weeks gestation: REM & non-REM
• by 38 weeks: several other sleep states
• newborns sleep about 17 hours per day,
throughout the day and night
• by 3 or 4 months, infants sleep more at
night than during the day, but night
wakings are common in infancy and
early childhood
Physical and Motor Development
Newborn States
State
Description
Quiet sleep Respiration is regular; eyes are closed and not moving;
(NREM)
the baby is relatively motionless
Active
sleep
(REM)
Muscles more tense; eyes may be still or display REMs;
breathing is irregular; spontaneous rhythmic startles,
sucks, and body movements
Drowsiness Opening and closing of the eyes; increased activity; more
rapid and regular breathing; occasional smiling
Quiet alert
Eyes open, scanning the environment; body is still;
respiration is more rapid than in sleep
Active alert
Awake, body and limb movements, less focused than in
the quiet alert state
Crying
Elevated activity and respiration rate; cry vocalization;
facial expression of distress
Physical and Motor Development
Waking States
Newborns have two basic modes of response to
stimulation: orienting & defense
– orienting – a heightened alertness that includes
behavioral localization toward the source of the
stimulation (a head turn to the source of a sound)
– defense – a behavioral action that involves withdrawal
from the source of stimulation
Physical and Motor Development
Waking States
Newborns will orient to stimuli of moderate
intensity and complexity
soft talking, moderate light levels,
and holding & rocking can enhance
alertness
Physical and Motor Development
Crying State
• Crying is an organized rhythmic activity
– there are different cries with different body responses
and cry sounds
• The frequency increases between birth and 2
months – then, it decreases
– similar in many cultures with different patterns of
infant care & response to crying
– infants cry more when parents are slower to respond
Physical and Motor Development
Crying State
Colic is crying in which
1. the infant cries at least 3 hours a day, on
at least 3 days per week, for at least 3
successive weeks
2. the parents find the crying very intense
3. the infant is otherwise normal; and
4. the infant is relatively unresponsive to
soothing & feeding
Physical and Motor Development
Crying State
• What causes colic?
– unknown
– not caused by digestive problems, sympathetic
nervous system arousal, or cortisol levels
• Factors related to colic
– mothers who were highly stressed during pregnancy
had higher chances of having a colicky baby
– colicky infants are more likely to have sleep problems
& to be inattentive, emotionally reactive, and sensitive
to touch, food, and other stimulation at 3 & 8 years
Physical and Motor Development
The Effects of Crying on Adults
• Adults perceive crying as an index of distress &
they try to figure out the source
– nonparents are as responsive as parents
– levels of arousal & responsiveness are equal for men
& women
• Child abusers show greater arousal & more
annoyance at cries than nonabusers
Physical and Motor Development
Soothing Infants
• nonnutritive sucking (NNS) immediately soothes
• swaddling reduces motor movement & startles;
keeps the infant calm for long periods
• daily massage enhances alertness, sleep, growth
& reduces stress and crying
• rocking can calm or put infants to sleep
• continuous sound can be calming, esp. when
moderately loud & of low frequency (e.g., singing
lullabies, humming)
Newborn States
Newborn state is important
1. the body needs periods of tranquility and rest to
consolidate resources for growth
2. attention to the environment depends on a stress-free
state of quiet alertness
3. state regulates the types of interactions newborns have
with their adult caregivers
Picture from: flickr.com
www.babyzone.com
Reflexes
Reflexes
– semiautomatic behaviors, triggered only by specific
elicitors
– look about the same every time they occur
– have to run their course once triggered
See examples of reflexes on YouTube, such
as the sucking reflex at
www.youtube.com/watch?v=KIgzqRaYJsg
http://health.allrefer.com/health/infantile-reflexes-moro-reflex.html
Reflexes
Purposes
• Primitive forms of orienting behavior
– e.g., rooting, sucking, and grasping
• Primitive defensive reactions
– e.g., the Moro reflex, reaction to a cloth on the face
• Elementary coordinations for later adaptive &
voluntary movements
– e.g., stepping, crawling, and swimmer’s reflexes
• No clear function
– e.g., the Babinski reflex – although the lack of a
Babinski response may indicate neurological disorder
Picture from: www.susheewa.com/blog/?p=866
Physical and Motor Development
Reflexes
• Reflexes are highly variable within & between
infants
– depends on individual differences, age, time since
last feeding & number of attempts to evoke the reflex
• Many disappear by about 6 months
– brain developments and other factors play a role
(e.g., weight & muscle strength in the stepping reflex)
Physical and Motor Development
Reflexes
In sum,
– newborn reflexes are extremely important for orienting
the infant to the environment & for protecting the infant
from harm
– movements related to reflexes are not simply
discharges in the brain, but depend on muscle
movement, weight, state, illness & many other factors
– reflexes play a role in the active development of the
muscles, leading to increased strength & coordination
Physical and Motor Development
Growth
Asynchronous growth: different parts of the body
grow at different rates & at different times
Physical and Motor Development
Sucking
Sucking is a reflex that is crucial for survival – it
changes over time & becomes more voluntary
Physical and Motor Development
Growth
The newborn’s arms & hands are among the least
controlled parts of the body
– arm & hand movements seem uncoordinated but
detailed video analyses show that they occur in
meaningful patterns
Physical and Motor Development
The Brain
Neuroscience – the study of the brain &
nervous system as it relates to
psychological & behavioral functions such
as moving, thinking, and feeling
Brain structures and functions
Major areas of the
brain
– brain stem
– limbic system
– cortex
Brain structures and functions
The prefrontal cortex is least developed in infancy
– connects limbic & cortical areas
– responsible for social & emotional
regulation
– involves thinking, reasoning, and judging
Picture from: www.cast.org
Brain structures and functions
Most developed in infancy
– brain stem – controls autonomic functions such as
breathing and heart rate
– limbic system – processes emotions and memories &
some body functions
• the important structures are the hippocampus, amygdala,
hypothalamus, and pituitary gland
Brain structures and functions
The Limbic System
• Hippocampus – important in
the formation of memories for
events & sequences (autobiographical memory)
– during the first 3 years, the hippocampus develops
links with the language & cognition areas of the cortex
• Amygdala – plays a role in the formation of
emotional memories, especially those around
fear & safety
Picture from: homepage.psy.utexas.edu
Brain structures and functions
The Limbic System
• Hypothalamus – links the brain to the endocrine
systems of the body via the pituitary gland
– regulates stress, body temperature, hunger, thirst,
and day-night rhythms
• The pituitary gland produces hormones
– for stress regulation, maintenance of body state,
sexual activity, milk production in nursing mothers, &
cell growth
Picture from: www.crnasomeday.com/anatpages/pituitary.htm
Physical and Motor Development
Two Hemispheres
• Right hemisphere – processes the majority of
social & emotional activity
– major development during the first 2 years of life
(emotion regulation, attachments)
• Left hemisphere – more specialized for thinking
& language
– develops more rapidly after the first 2 years
Fetal and infant brain development
A critical period
The period from the 5th gestational month through
the age of 3-4 years is a critical period for the
development of the human brain
– To understand why, we need to look at the structure of
neurons – information storage
& transfer cells
Fetal and infant brain development
A critical period
The brain develops by four basic processes:
1. New cells are created via mitosis during the prenatal
period
• most development after this occurs by making cell connections
& by pruning of unused neurons
2. The brain becomes more efficient
• glial cells guide growth & migration of neurons (prenatally)
• myelination increases the speed of conduction along the axon
(mostly right before & after birth)
Fetal and infant brain development
A critical period
3. Synaptogenesis – cells grow more dendrites & axon
terminals & make more synaptic connections &
neurotransmitters
Fetal and infant brain development
A critical period
4.The role of experience
• experience expectant pathways await specific
environmental input
• e.g., pain elicits crying
• experience dependent pathways are based on
unique experiences
• those that are used most become strengthened; those that
are used the least eventually die
Optimal & non-optimal
brain development
Neural plasticity – the ability of the brain & nervous
system to seek novelty, learn, and remember by
continuing to alter the patterns of connections
between neurons
– intact brains retain plasticity throughout life
– impairments in social & linguistic skills, along with brain
abnormalities, develop in infants reared in orphanages
or infants not exposed to appropriate language
Optimal & non-optimal
brain development
Each baby in the first two years of life comes
to assess the social world as either a safe
or a threatening place
Optimal & non-optimal
brain development
Neuroception – nonconscious evaluation of safety
or threat, by the nervous system and not the
conscious mind (Porges, 2004)
Optimal & non-optimal
brain development
Neuroception is regulated by
– Sympathetic & parasympathetic nervous systems
• Sympathetic nervous system – prepares the body for action
• Parasympathetic nervous system – allows the body to relax,
slow down, process information, engage socially, learn & grow;
the vagus nerve is most responsible for neuroception
– The HPA-axis
The HPA-axis
When stress occurs:
Hypothalamus: CRH
Pituitary gland: ACTH
Adrenal glands: Cortisol
Optimal & non-optimal
brain development
• Cortisol prepares the body for action in response
to stress
– increases blood sugar needed for action
– feeds back into the limbic system where it heightens
the formation of memories related to the stressful event
• If stress is persistent, cortisol is overproduced
– prolonged activation of cortisol suppresses the immune
system & physical growth
– too much stress leads to a tendency to feel fear and
threat in the future & can lead to post traumatic stress
disorder (PTSD)
Optimal & non-optimal
brain development
Optimal & non-optimal
brain development
In sum, the first 3 years of life are critical for brain
development
– for the development of the limbic & prefrontal parts of
the right brain, which is dependent on the quality of
love, emotional sharing, & social engagement received
& perceived
– not for cortical & left-brain processes like reading,
math, thinking, or musical ability
Optimal & non-optimal
brain development
It is more important for infant brain
development to spend quality one-on-one
and family time than letting the baby play
for long periods with expensive toys, or
listen to Mozart, or watch baby TV
programs
Perceptual Development
• Ecological perception – experience that relies on
direct perception through the senses
– the senses form the basic ways in which we are
connected to the environment
• Newborns have the ability to see, hear, taste,
smell, and feel – although not as focused or
discriminating as adults can
Perceptual Development
Newborn visual acuity & visual processing are
poor but improve rapidly
– visual acuity is only 20/500 on average, due to an
immature nervous system
– the newborn’s visual world is rather blurry, but the
infant can see colors
– as a result of experience-dependent brain
development, visual acuity improves to nearly 20/20 by
6 months
Perceptual Development
• Oculomotor skills – movements that the eye
makes to
– bring objects into focus
– follow moving objects
– adjust for objects at different distances
• Newborns’ tracking of moving objects is jerky,
and they only follow slowly moving objects
– at 6-8 weeks, following becomes more adultlike
Perceptual Development
Scanning – the eye traces a path across a visual
stimulus in small, rapid movements
Perceptual Development
• Oculomotor control adjusts the eyes to see
objects at different distances
• Depth perception – the ability to judge the
relative distances between two objects &
determine whether objects are close or far
– The ability to compare the two retinal images (and
therefore to see distance) emerges slowly between 3
& 6 months
Perceptual Development
• Can newborns see patterns?
– Studies show that newborns can detect differences
between visual images & seem to prefer some
images more than others
• Newborns prefer
– objects with clearly marked edges & outlines
– circular patterns over straight lines
– the external contours of a figure, especially if the
edges are sharp
Perceptual Development
Newborns have perceptual preferences that are
likely to bring them into contact with things that
enhance their survival
– infants prefer faces over other objects
– 1-day-old infants change their sucking response to see
a picture of their mother’s face rather than the face of
an unfamiliar female – but not when the mother is
shown wearing a scarf
– newborns prefer to look at faces judged by adults to be
more attractive
– they also prefer faces in which the other person’s gaze
is directed toward the infant rather than averted
Auditory Perception
• The auditory system is more mature at birth than
the visual system
• Auditory sensitivity (sensitivity to sounds)
involves loudness & pitch
– newborns can hear sounds of 40-60 dB but only
sounds from 50-70 dB can awaken them
– they prefer sounds in the middle range; higher pitch
over lower pitch; sounds made up of more than one
note; and melodic sequences over a jumble of
unrelated notes
Auditory Perception
The most common source of such sounds is an
adult female voice, talking or singing
– newborns prefer to listen to a song or story that their
mothers had sung or read aloud 2 weeks prior to birth
over an unfamiliar song or story
– newborns seem to prefer heartbeat sounds similar to
those they must have heard prenatally
– infants can distinguish the voice of their own mother
from the voices of other women.
Auditory Perception
How do newborns distinguish speech sounds from
different people?
– They may detect overall patterns of rhythm & pitch that
differentiate one person from another
– They may be able to hear differences among syllables
that give them cues about a speaker’s uniqueness
• By 1 month, they distinguish two very closely related speech
sounds (e.g., “p” and “b”) and by 2 months, they recognize
vowel differences
Taste
Newborns seem to distinguish the four basic tastes:
sweet, salty, sour, and bitter
– They show different responses to
these four tastes
– Sweet fluids seem to relax (see
pictures)
– Sour, bitter & salty tastes elicit
negative responses
Smell
• Newborns can differentiate between odors (incl.
vinegar, licorice, & alcohol)
– In response to unpleasant odors, they make faces of
disgust and turn away
• They may recognize their mothers by odor
– Newborns turn their heads more to a pad containing
their mother’s breast milk than to one containing
another woman’s milk
– Breast-fed infants can also recognize their mother’s
underarm odor & perfume & they prefer the smell of
any breast milk over other types of smells
Touch
Many reflexes are stimulated by touch & newborns
show changes in behavior & heart rate in response
to tactile stimulation
– They adjust hand & mouth movements when feeling
soft vs. hard objects, or smooth vs. textured objects
– They visually recognize an object they had previously
touched, but not the other way around
– In response to medical procedures (e.g., injections,
circumcision), infants show increased distress and may
exhibit sleep disturbances
Perceptual Development
In sum,
– newborns perceive with all their senses and their
sensitivity improves rapidly over the first few weeks and
months, due to brain development & experience
– many forms of stimulation have no particular meaning
for the infant but others are meaningful (e.g.,
recognizing mom, crying in response to pain)
Cognitive Development
Newborns possess a number of ways to process
information that are referred to as cognition –
including learning & memory, orienting &
habituation, and imitation
Cognitive Development
• Classical conditioning
– possible when the unconditioned stimulus (UCS)
evokes a rewarding natural response, such as a
sweet taste
• Operant conditioning
– once infants learn the connection between their
behavior & a reinforcement, they can signal their
preferences, using sucking rate or head turn
– newborns can remember (e.g., a word repeated by
mom) for appr. 24 hours & they prefer familiarity
Cognitive Development
• Habituation is the decline in strength of
responding after repeating the same stimulus;
dishabituation is renewed interest
• Newborns’ motor and heart rate responses have
been found to habituate to auditory stimuli,
visual stimuli, and tactile stimuli
• Habituation can also be shown in premature
newborns and even in infants born without a
brain cortex (anencephalic)
Newborn Imitation
Meltzoff & Moore (1977) showed that 12- to 21day-old infants could match tongue protrusion,
lip protrusion, mouth opening, hand opening,
and hand closing
Newborn Imitation
• These findings have been replicated
– One study showed that newborns also matched
moving objects
– One study found imitation of surprise, happy, and sad
facial expressions
• Other studies failed to replicate these findings
– babies show a wide variety of gestures following the
model
– there are wide individual differences
Newborn Imitation
Newborn imitation may be a way of relating to
people
– Infants who imitated more at birth gazed away from
their mothers less at 3 months
– Newborns’ imitation of tongue protrusion showed a
different pattern of heart rate change compared to when
they initiated the same movement (as if to get a
response)
– 6-week-old infants spontaneously reproduced the
imitative response they had learned 24 hours earlier
when seeing the adult model
Newborn Self-Awareness:
The Emergent Self
Evidence for early self-awareness comes from
studies that show
– Newborn imitation (distinguishing own movements from
the movements of others)
– Differential rooting (more when touched by someone
else than by touching self)
– Differential crying (more when they hear tape
recordings of other infants’ cries)
Newborn Self-Awareness:
The Emergent Self
The emergent self is the sense of
self-sameness over time in
behavior, feelings, and states of
arousal
Cognitive Development
In sum,
– newborn cognition is limited to some simple forms of
learning, memory, habituation, imitation, and selfawareness
– early learning and memory are fundamental to survival
• recognition of maternal sounds and smells
• learning to orient to sweet fluids & milk
• learning to avoid noxious smells & tastes
– newborns prefer familiar sights, sounds, tastes, &
feelings, and do not like to be stressed or challenged
Emotional
Development
Newborns can feel distress, contentment, disgust,
interest, & surprise
– newborns ‘savor’ sweet liquids
– they cry, thrash about, stiffen their bodies when
distressed
– when attending to faces, social interaction, & moving
objects, they may show expressions of interest &
surprise
Emotional Development
• Some expressions (e.g., smiling) do not occur
with any clear link to the situation
• Emotional development depends in part on how
newborn forms of expression are interpreted by
adults
Family and Society
Adults and infants have mutually complementary
communications that get their interaction started
and set the stage for later emotional ties
– Attachment – the maintenance of
mutual proximity over time
– Bonding – skin-to-skin contact
immediately after birth,
between mother and infant
Picture from: raisingchildren.net.au
Family and Society
• Mothers & fathers explore the
newborn’s body in a patterned way
when given the opportunity –
apparently important for survival
• However, there is no conclusive evidence linking
these first few minutes of contact with later
attachment security
– When there is no immediate post-birth contact, lasting
attachments can still be formed
Picture from: www.smh.com.au
Family and Society
There is also a social-psychological component
that may form the basis of later interpersonal
communication and attachment
– early feeding patterns (suck-pause, jiggle-stop, suckpause, jiggle-stop, etc.) precede later social discourse
– animated adult faces & brightly colored objects prolong
periods of alertness
– the duration of parent-infant face-to-face play & infant
attention gradually increases over the first 2 months
Family and Society
• Studies of large-scale national samples show
that fathers spend 20-35% as much time as
mothers in direct infant care
• Men’s ability to participate in
parenting tasks depends on
the amount of social support
they receive, particularly from
their partners
• The more involved fathers
are, the more involved they
become
Family and Society
• Father-infant and mother-infant interaction
can be enhanced by specific interventions to
orient parents to their newborns
– E.g., 12-week-old infants whose fathers had
been trained in massage & bathing were more
likely to interact with their fathers & fathers were
more likely to be involved with their infants than
non-trained fathers
• Parenting occurs within a family system
Picture from: www.childways.co.uk
Family and Society
• First-time parents appear more hesitant with
their babies, but this difference disappears after
several months
• Firstborn newborns receive
more caregiving interaction
Experiential Exercises:
Sucking
• Sucking is the first mouth movement that we
master –later we build on our infant sucking
ability as we learn to control thousands of other
mouth & face movements
– Lie on your right side in a fetal position, and place
your hands close to your mouth
– Gently protrude your lips & tongue and experiment…
– Now try sucking movements…
• Many people experience a deep relaxation of
the face after doing this lesson. What was your
experience?
Experiential Exercises:
Somatic Awareness of the Hands
•
•
Sit in a chair & close your eyes – become
aware of your body in the chair
Now, notice your hands – what position are
they in? How do they feel?
– Slowly move your hands…
– Now, slowly curl & uncurl your right hand – then the
left
– Let your hands explore your body, clothes, the chair,
& each other
– Open your eyes and look at your hands as if you’ve
never seen them before
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