PSY210: 2. Prenatal Development and the Newborn Flashcards
Prenatal Development
fetus has its own environment in which it behaves, experiences, remembers
newborn capacities + what it has yet to achieve
Prenatal Development
Development begins at conception
Conception occurs when ovum + sperm form zygote
(fertilized egg)
5 days, the zygote floats down the fallopian tube
Prenatal Development
5th day after conception zygote implants itself in the uterine wall
From implantation until 49th day after conception, the organism is called an embryo
From the 8th week until birth, the organism is called a fetus
Three Trimesters
Prenatal Development
change starts at conception
embryo phase: how much fundemental growth happen - organ, major systems, most rapid development
if something goes wrong, they are the most detrimental
speed is a safeguard: short window for hazardous time period
Prenatal Development
period of fetus: 1st - connect + organize systems, 2nd - nervous system development, 3rd - myelination, causes the brain to increase in weight exponentially causing the brain to turn upside down in preparation in birth
Zygote
2 weeks
Fertilization
Implantation “Start of placenta
Embryo
6 weeks
“Arms, legs, face, organs, muscles all develop
“Heart begins beating
Fetus
30 weeks
“Growth and finishing”
World of the Fetus
it behaves - moving, practicing moving, breathing
it experiences smell, hearing
remembers it after born
Fetal Behaviour
fetus is an active contributor to its own development.
Swallowing amniotic fluid promotes normal development of palate + aids in maturation of the digestive system
Fetal Behaviour
By 12 weeks after gestation, most of movements that will be present at birth have appeared
prenatal to postnatal continuity
kicking, grasping, baby steps, touching mouth, suck thumbs
practicing behaviours they need later on
Fetal Behaviour
fetus breath in amniotic fluid to develop lungs
byproducts is tasting + smelling amniotic fluids
behaviours exist in fetus continues to exist when its born
the only thing that changes is the environment
Behavioural Cycles
Rest-activity cycles become stable during second half of pregnancy
Circadian rhythms are also apparent
when is it most active?: fetuses active in squirts
circadian rhythms develops later on
Behavioural Cycles
Near end of pregnancy, fetus’s sleep + wake states similar to those of the newborn
fetus responds to movement of its mother
adjusting its behaviour to environment - to fit its mother behaviour
Fetal Experience
sensory structures present relatively early in prenatal development + play vital role in fetal development + learning
Prenatal visual experience is negligible
Fetal Experience
Fetus experiences tactile stimulation as result of its own activity + tastes + smells amniotic fluid
responds to sounds from at least the
6th month of gestation.
experience through its senses
Fetal Experience
no perceptual light in womb - no visual experience
tactile is fully developed - informs fetus that it is separate from others
touch gives them a double touch - feel it on hands + face with hand
Fetal Experience
touching others: it is not me i’m touching - there’s me + everything else
preference for flavours: what they’re mom’s eat
preference for sweet taste, fetal swallowing increases when increased sweetness of amniotic fluid
Fetal Learning
As early as 32 weeks, fetus decreases responses to repeated or continued stimulation, a simple form of learning called habituation.
they remember because they demonstrate habituation
Fetal Learning
reduction in response to given stimuli
reduction in heart rate = paying attention - goes back to normal
as soon as they learned that sound they stop paying attention
Fetal Learning
Newborn infants have been shown to recognize rhymes and stories presented before birth.
Newborns also prefer smells, tastes, and
sound patterns that are familiar because
of prenatal exposure
Fetal Learning
sucked in a specific pattern, mother played cat in the hat, what they had heard before
they can recognize the poems
orientate toward it when they recognize it from being a fetus
Environmental Influences
Teratogens environmental agents that have the potential to cause harm during prenatal development.
Timing is a crucial factor
in the severity of the
effects of potentially
harmful agents.
! Many agents cause
damage only if
exposure occurs during
a sensitive period in
development.
Environmental Influences
if present during certain time period (early on) it is more likely to be damage
fundamental development - more dangers
Sensitive Periods
darker the green, more likely to cause harm if teratogens are present
all bars are present during embryonic
CNS vulnerable through all stages - brain is complex
Teratogens
Most teratogens show a dose-response relation
Increases in exposure to potential teratogens are associated with greater probabilities of fetal defects and with more severe problems.
Teratogens
we don’t have no evidence on how much of the teratogens
there are several teratogens, we don’t know how they interact
Cigarettes
Cigarette smoking during
pregnancy is linked to
retarded growth and low
birth weight.
Smoking related to mild and severe psychiatric morbidity
underweight, less progressed
Cigarettes
smoking related more likely to be described antipsychotics + antidepressants
reduces oxygen she intakes which is what provides fetus with oxygen
nicotene crosses placenta - brain is developing with presence of nicotene
as adolescents, they have to be prescribed things for those who are trying to quit smoking
their brains are used to nicotene
Alcohol
Fetal Alcohol Syndrome is a set of physical, mental, and neurobehavioural birth defects associated with alcohol consumption during pregnancy and is the leading known and preventable cause of mental retardation
Alcohol
decrease intelligence
reduce oxygen, fermentation requires extra oxygen
developing in alcohol rich environment
only seen in mothers who consumed it excessively throughout
State of Arousal
infant’s level of arousal + engagement in environment
Ranges from deep sleep to intense activity
Six States of Arousal
Active sleep Quiet sleep Crying
active: 8 hours, moving
quiet: isn’t moving 8 hours
crying: 2 hours
Six States of Arousal
Active awake Alert awake Drowsing
active awake: physically awake 2.5
alert awake: still, but they follow with eyes 2.5
drowsing: state between awake + asleep 1 hour
there is variability, they switch all the time
Newborn States
Develop before birth
! Give evidence of some important principles of human behaviour:
human behaviour is organized
human beings are not passive
Newborn States
they aren’t born with random behaviour
organized from birth - even prior
we are not inherently passive - choosing for themselves
adjust to environment over time
Sleep
Newborns sleep twice as much as young adults
The pattern of two different sleep states changes dramatically
sleep is important - REM: eyes moving, moving, we associate with dreaming, more rem
NREM: non active
Sleep
REM (rapid eye movement) sleep: an active sleep state associated with dreaming in adults and is characterized by quick, jerky eye movements under closed lids
! Non-REM sleep: a quiet or deep sleep state characterized by the absence of motor activity or eye movements and by regular, slow brain waves, breathing, and
heart rate
Proportion of REM and non- REM Sleep Across the Life Span
REM sleep constitutes 50% of a newborn’s total sleep time and declines rapidly to 20% by 3 or 4 years of age.
Why is there such a high percentage of REM sleep in infancy???
According to autostimulation theory, brain activity during REM sleep in the fetus and newborn makes up for natural deprivation of external stimuli and facilitates the early development of the visual system and the brain.
REM-Sleep
memory consolidation/learning
helps develop underdeveloped brains, makes up for lack of stimulation as a fetus
plays catchup for lack of stimulation
newborn in bland rooms with minimal visual stimulation had more rem sleep
memory consolidation: helps us form synapses responsible to recall info
lots of new info to learn - experiences so many things that they need to consolidate
Crying
Early in infancy, crying reflects discomfort or frustration.
! Crying gradually becomes more of a communicative act.
! With experience, parents become better at interpreting the characteristics of the cry itself.
Three types of crying
Basic, Angry, and Pain adults can start distinguishing basic: discomfort, hungry angry: increases in intensity + duration pain: starts loud + holds breath, pants they sound similar
Parental Response to Crying: Is it better to respond promptly or delay response to an infant’s crying?
child needs a sense that they can trust the world + parents
middle - pain cry right away
basic - better to wait
in the long run - not much diff
if you were able to differentiate, just slightly less crying later on
Newborns’ Reflexes
#Infants are born with innate primary reflexes #An inborn, automatic response to a particular form of stimulation #Two purposes for infant reflexes #Survival #Form basis for complex motor skills
Newborns’ Reflexes
One primary reflex is the Babinski (fanning of toes when foot stroked) - no known function
behaviours we are preprogrammed with - no free will
born to help us survive + helps practice more complex skiils
babinski: don’t do it they have severe CNS problems
Eye Blink
Stimulation Shine bright light at eyes or clap hand near head Response Infant quickly closes eyes Age of Disappearance Permanent reflex Function Protects infants from strong stimulation can go away, but for the most part it doesn’t
Rooting
Stimulation Stroke cheek near corner of mouth Response head turns toward source of stimulation Age of Disappearance 3 weeks (becomes voluntary) Function Help infant find the nipple born ready to find nutrition
Sucking
Stimulation Place finger in infant’s mouth Response Infant sucks finger rhythmically Age of Disappearance 4 - 6 months Function permits feeding
Swimming
Stimulation
Place infant face down in pool of water
Response
Baby paddles and kicks in swimming motion
Age of Disappearance
4 - 6 months
Function
Help infant survive if dropped into body of water
infant grasp to mom + squirm to keep themself buoyant
Moro
Stimulation
Hold infant horizontally on back and let head drop slightly, or produce a sudden loud sound against a surface supporting infant
Response
Infant makes “embracing” motion by arching back, extending legs, throwing arms outward, and then toward the body.
Age of Disappearance
6 months
Function
In human evolutionary past, may have helped infant cling to mother
grasp at you interpret it as falling
Palmar grasp
Stimulation Place finger in infant’s hand and press against palm Response Spontaneous grasp of adult’s finger Age of Disappearance 3 - 4 months Function Prepares infant for voluntary grasp prepares them for grasping without experience
Tonic Neck
Stimulation
Turn baby’s head to one side while lying awake on back
Response
Infant lies in a “fencing position.” One arm extended in front of eyes on side to which head is turned, other is is flexed.
Age of Disappearance
4 months
Function
May prepare infant for voluntary reaching
Stepping
Stimulation: Hold infant under arms and permit bare feet touch a flat surface
Response: Infant lifts one foot one after another in a stepping response
Age of Disappearance
2 months
Function
Prepares infant for voluntary walking
some reflexes combine to produce complex
stepping, rooting + sucking combine to create an elaborate action
on a mom’s stomach, finds the mom’s nipple to feed
Newborn Sense of Touch
Sensitive to touch on mouth, palms, soles, genitals
Highly sensitive to pain
$ relieve pain with anesthetics, sugar solution, gentle holding
$ physical touch releases endorphins
Newborn Sense of Touch
highly developed
know they need to be changed so they cry
they experience pain much worse
our frontal lobe engage in inhibition, we can build up a tolerance
they can’t regulate emotions, they can’t ignore it
changes to response to future pain experiences
remember pain experiences,
stroking the cheek soothes them, high of endorphins
helps them form connections
Newborn Senses of Taste and Smell
Prefer sweet tastes at birth
Quickly learn to like new tastes
Have odour preferences from birth
Can locate odours and identify mother by smell from birth
can taste sweet sour, bitter,
not sure if they don’t taste salt or indifferent
ability to taste salt at 1 - then they can eat solid food
prefers salt then ready to have solid food
can learn preference for taste as long as they are exposed
Differences in Newborns’ Smell Sensitivity
preexposed during end of pregnancy: they like it
never smelled it before: hate it, move away
smart enough to move their head away in a protective fashion
Newborn Sense of Hearing
Can hear a wide variety of sounds at birth
Prefer complex sounds to pure tones
Learn sound patterns within days
Sensitive to voices and biologically prepared to learn language
Newborn Sense of Hearing
differentiate smells of their own mom
can differentiate different notes that are similar
like more complex sounds/patterns
humans are innate pattern perception machines - means its consistent
can remember sound patterns
sensitive to human voice, brain specifically attuned to hear + respond to human speech
Newborn Sense of Vision
Least developed sense at birth
$ visual structures in eyes and brain not fully formed
Limited acuity
Scan environment, track moving objects
Colour vision improves in first two months
limited visual acuity - vision is fuzzy
both levels at brain + visual structures
Newborn Sense of Vision
scanning: where you look, limited to the periphery, lots of detail in face
they like looking at complexity, but they have low acuity
hard to track, colour perception is less, needs more experience to differentiate
no experience with tracking, stutters, takes prediction to follow things
know they should move their eyes smoothly when we’re older
Body Growth
Gain 50% in height from birth to age 1
!75% by age 2 Grow in spurts
gain “baby fat” until about 9 months, then get slimmer
they gain much more weight + height
growth pattern is not consistent
they grow in spurts: baby fat insulates child - poor at regulating body temp
need it for the spurts to keep us warm
Growth Trends: cephalocaudal
“Head to tail”
Lower part of body grows later than the head
Growth Trends: proximodistal
Near to far”
Extremities grow later than head, chest, and trunk
head grows first + rest of body needs to catch up
centre of body mass grows first, why they can’t move around
proximodistal reverses itself in adolescence
Neurones, Glial Cells, & Myelin
process of both growth + destruction*
neurogenesis: higher than any later point
through apoptosis + synaptic pruning - removal of neurons that are useless
too many = interference
Lateralization of Cerebral Cortex
specialization
at birth more plastic, more functions
reduction in brain plasticity
Left Hemisphere
Sensory information and control of right side of body
Verbal abilities
Positive emotion
Sequential, analytical processing
Right Hemisphere
Sensory information and control of left side of body
Spatial abilities
Negative emotion
Holistic, integrative processing
Brain Plasticity
In infants and young children, parts of brain are not yet specialized.
Recover better from brain injury
! language recovers better than spatial skills
! still have some problems with complex mental skills
Older children, even adults, have some
plasticity.
Brain Plasticity
ability to do thing it wasn’t able to do
left side damage, more likely to recover them than when you have damage to right side
left side can’t compensate for right side damage
spatial skills existed much longer, but language is more recent
Sensitive Periods in Brain Development
Stimulation is vital when brain growing rapidly
Experience-expectant growth
! ordinary experiences “expected” by brain to grow normally
Experience-dependent growth ! additional growth as a result of specific learning experiences
Sensitive Periods in Brain Development
sensitive periods for experience expectant growth
will never the get the brain to develop - visual experience
no stimulation - brain kills that part of the brain
experience-dependent: not evolutionary expected, everything else
sensitive periods can be small or brain
Motor Development: Sequence and Trends
Gross motor development
! crawling, standing, and walking
Fine motor development ! reaching and grasping
Sequence is fairly uniform, though individual rate of motor progress differs
Cephalocaudal and proximodistal trends
Motor Development: Sequence and Trends
large movements = gross
specialized skills, picking up things: fine
sequence roughly at same amount of time
early gross motor skills no problem - not predictive of athletic ability
first can control head, then body, then extremeties
Motor Skills as Dynamic Systems
Increasingly complex systems of action with each skill
Each new skill is joint product of: ! CNS development
! body’s movement capacity
! child’s goals
! environmental supports
Motor Skills as Dynamic Systems
brain has to be in position, muscles have to be ready
child has to have a purpose
support: swaddling more common in asia, prevents them from moving
environment has to support them to move
Milestones of Reaching and Grasping
Prereaching Reaching ! with two hands, then one ulnar: grasp adjust grip to object ! move objects from hand to hand pincer grasp: ability to pick up objects with 2 fingers
Milestones of Reaching and Grasping
moves from gross to fine motor movement
prereaching: sway arms whenever anything enters visual field
reach: volitional act, realize they only need 1
ulnar: volitional, choose to close hand in specific way, before they reach it, they shape their hand
Developments in Hearing
4–7 months
Sense of musical phrasing
6–8 months
“screen out” sounds from non-native languages
7–9 months
Recognize familiar words, natural phrasing in native language
Developments in Hearing
can tell diff betw similar sounding patterns
they start ignoring sounds that are not in their language
use it to lose it 6-8 months
7-9: can recognize when it’s 2 separate units of language
perceptual capacities are highly developed especially hearing
geared to recognize patterns + remember them
Improvements in Vision
Supported by rapid maturation of eyes and visual centres in brain Improvements ! 2 months: focus and colour vision 6 months: scanning & tracking ! 6–7 months: depth perception
Improvements in Vision
6 months: starts looking at finer details, smoothly follow moving objects
6-7: how far away objects are
Milestones in Depth Perception
3–4 weeks " Sensitivity to motion cues 2–3 months " Sensitivity to binocular cues 6–7 months " Sensitivity to pictorial cues " Wariness of heights
Milestones in Depth Perception
kinetic cues: cones moving quickly, close to you
child moves its head first, realizes hands moves a lot not everything else
binocular cues: using info from both eyes
closer it is in your face, disparity increases betw both eyes
pictoral cues: amount of detail, artists use to depict depth
The Visual Cliff
what age do they recognize diff in height
standing alters how they see world
Milestones in Face Perception
Birth– 1 month
Prefer simple, facelike pattern
2–4 months
“ Prefer complex facial pattern to other complex patterns
“ Can distinguish strange from familiar faces
“ Prefer mother’s face over stranger
5–12 months
Can perceive emotional expressions on faces
Milestones in Face Perception
like to look at human faces
can more reliably differentiate between mom + strangers
preference of mom’s face
emotional expressions requires experience - need to considerable
Early Face Perception
humans are orientated to human faces
lost humans orientate toward parents
look at mom’s face more frequently, more attachment
we see humans more than anything else, always around humans
familiarity breeds liking
face is an organized pattern - we like patterns
Intermodal Perception
Intermodal perception allows us to make sense of intermodal stimulation— simultaneous input from multiple modalities, or sensory systems—by perceiving objects and events as unified wholes.
infants are born to expect intermodal + that they should reinforce one another
these senses should make sense
when they don’t line up, we know something is wrong
Milestones in Intermodal Perception
Birth Detect amodal sensory properties 3–4 months Relate speech sounds to lip movement 4–6 months Perceive unique face-voice pairings of unfamiliar adults
Milestones in Intermodal Perception
amodal: surprised in mistakes
amodal: looking at + hearing at the same time - senses that reinforce
expect senses to go together from birth
figure out when speech doesn’t match with lip movement
learn who’s saying it
Theory of Perceptual Learning
Infants:
search for invariant features of the environment
note stable relationships between objects in environment and themselves.
! affordances
gradually detect finer and finer features: differentiation
Theory of Perceptual Learning
humans are pattern perception machines*
there must be a purpose because we can do it so early on
it is how we learn + gather info
looking for patterns in perceptual field
look for relationship betw pattern + themselves - what does this do for me
gradually refining interpretation - differentiation
Operant Conditioning Terms
Important Reinforcer = parental attention
attention increases likelihood for behaviour
control increased behaviour in case you reinforce bad behaviour
Habituation
decrease in responsiveness to repeated stimulation reveals that learning has occurred.
# The infant has a memory representation of the repeated, now-familiar stimulus.
sign that children have learned
not a learning mechanism in itself
Using Habituation to Study Infant Memory and Knowledge
novelty preference: infants tend to look at novel stimuli vs. stimuli they have habituated to
once they have equal exposure, looks back to something familiar
familiarity breeds liking
if exposed to it more, it makes sense to gather more info on it
Imitation
Newborns have ability to imitate
reflex or voluntary capacity?
Mirror neurones offer biological explanation
Powerful means of learning
Helps facilitate positive relationships
copying behaviour
innate ability to imitate facial expressions
Imitation
8 hours after they’re born they can imitate expressions
it was a reflex, over time it becomes volitional
mirror neurons: activate in similar patterns betw watching + doing
by 1, simply watching once, sufficient to engage in simple action
facilitates: because they imitate, it creates a bond
