PSYC228_Chap3 Flashcards
weight + height gains occur most rapidly in
first 6 months of life, then slow
cephalocaudal growth
pattern of growth procedding from the head downward
proximodistal grwoth
pattern of growth proceeding from the inside of hte body outward through limbs
2 parts of nervous system
CNS (central nervous system) (control centre for body)
PNS (peripheral nervous system) (connects CNS to intrnal orgals, bones, muslces - carries messages from CNS)
cerebral cortex
uppermost protion of brain _ centre largely responsible for complex brain functions
(though, perception, language production, _ motor function)
most of brain growth occurs during
infancy
neuron
brain or nerve cell that serves as basic building block of nervous system
axon
nerve fibre that typically sends electrical impulses away from neuron’s cell body
dendrite
branching structure arising from cell body that typically receives electrical impulses from axons of neighbouring neurons
primary brain job during early infancy is
making + strengthening connections between neurons
connection is made between neurons when
axon of one neuron sends message/electrical impulse that is received by dendrite of anotehr neuron
synapse
space between neurons (space betw the axon and dendrite) across which messages are sent + received
myelination
process thru which axon of a neuron is coated with fatty tissue which serves as insulation + enhances speed of firing
synaptic pruing
process by which brain removes unused synapses thru redirection nutrition, cell injury, + cell death
humans are made highly felxible because
the brain overproduces + prunes synapses
brain is plastic
different cultural contexts + experiences result in
different kinds of connections being made and kept
plasticity
changes in the brain resulting from out interactions with the environemnt;
influenced by age-related change
brain plasticity decreases with
increasing age
2 types of processes related to early experience + brain development
experience-expectant processes
experience-dependent processes
experience-expectant processes
brain development that occurs based on environmental experiences that all members of the species typically encounter
experience-dependent processes
brain development that occurs based on unique environmental stimuli shared only by individuals in particular environmental circumstances
neaurons need to be
stimulated in order to develop new connectiosn
during teh first 3 months after birth, newborns sleep betw
10-19hrs/day
2 primary categories of sleep
rapid-eye-movement REM
non-rapid-eye-movement NREM
REM
rapid-eye-movement sleep
sleep state during which rapid _ random eye movements, intense + irregular brain-wave activity, + dreaming occur
NREM
non-rapid-eye-movement sleep
sleep state during which rapid-eye-movement + dreaming do not occur + brain-wave activity is slow + regular
reflex
simplest + quickest neural pathway
involve few neurons (a sensory neuron + motor neuron)
involuntary response to a stimulus
newborn reflex
inborn automatic response to stimuli, which may disappear before the end of the first year
reflexes provide
behavioural messure of the development of the nervous system + often incorporated into newborn assessments
at birth there are ~
270 bones
but then fuse in spinal column + head
plantar grasp
flexing of toes
readiness to walk
appears 28wks gestation
9 months integration
babinski reflex (plantar resposne)
newborn relfex that is teh extension of the big toe + fanning out of other toes
failure indicates neurological abnormality + interferes with walking
from birth to 12-18 months
integrated after walking
moro reflex
newborn reflex
the quick fall test, shoulders pull back + fingers/elbows/wrists extend
asymmetry may indicate injury to peripheral nerves in upper extremities
from 28 wks gest., integrated betw 5-6 months
palmar grasp
infant’s fingers flex arnd finger
infant begins reaching for objects to grasp
from 10 wks gest., integrated arnd 4-6 months
rooting + sucking reflex
stroke infant from lips to cheek, infant turns head to follow finger + suck it
absence of this reflex indicates neurological impairment
28 wks gest, integrates at 3 months
stepping + walking reflex
alternating, thythmical coordinated steps
absence indicates possible disease or prenatal drugs
37 wks gest., integrated at 2 months
crawling reflex
infant on abdomen pulls legs underneath + pushes forward
essential for voluntary crawling behaviour
from brith to integration at 3-4 months
tonic neck
infant lying on back will bring its arms into fencer’s position when head turned to the side
helps infant explore 1 side of environment at a time by coordinating sensing on taht same side
brith, to integration at 6-7months
during the first 2 yrs, muscle fiber becomes more
differentiated + innervated
gross motor skills
motor skill that relies on large muscles like legs + arms
find motor skills
motor skill that relies on small muscles like fingers
nerborn movements are mostly
involuntary responses to sensory system
posture
way a person holds his/her body as a whole
integrating process taht connects + provides foundation for all gross motor activities
infants have
no voluntary postural control at birth
most influential cognitive development theorist
Jean Piaget
sensorimotor stage
Piaget’s first stage of cognitive development - infants develop from reflex-driven organisms to more complex + symbolic thinkers
goal of Piage’ts sensorimotor stage
develop from reflexive organism to more.complex + symbolic thinker
key processes that drive change from one substage to another in Piaget’s theory?
assimilation + accomodation
assimilation + accomodation underlie ongoing developement of
schemes
schemes
mental structures taht help us organize + process info
object permanence
understanding that an object continues to exist even when it’s not immediately present or visible
A-not-B error
mistake made by children in Piaget’s sensorimotor stage as they search for hidden object in a location where it has been repeatedly placed but is no longer hidden
object permanence + understanding of A-not-B error may be accomplished
at younger ages than Piaget thought
implicit memory
repetition of a behaviour, such as a leg movement to make an object move, taht occurs automatically + without apparent conscious effort
explicit memory
repetition of a behaviour that shows a clear, observable, conscious effort to recall an event, such as when an infant imitates at a later time a behavioiur seen earlier
Piaget’s sensorimotor substages:
reflexes (birth-1 month)
habits + repetition (1-4m)
actions with objects (4-8m)
Coordination of schemes +
intentional behaviour (8-12m)
using objects in novel ways (12-18m)
symbolic thought (18-24m)
deferred imitation
ability of 6-7m old infants to imitate an action after a delay + not in presence of a model
habituation
dec responding to a stimulus that occurs because of continuous presentation of the stimulus
dishabituation
inc responding to a stimulus, usually bec it is novel
habituation occurs more
quickly with age
later IQ is correlated with
speed of habituation in infancy
receptive language
language that an infant understands but may not be able to produce
knows what words mean, but can’t use them
expressive language
language that an infant can produce
words that are understood + can be used by infant
infancy language milestones
1-4m respond to voices/make sounds when spoken to
1-syllable sounds, coos
4-7m babble, produces variety of syllables
7-10m know when words begin + end, comprehend gestures
repeat 2-syllables in a row (mama)
10-13m respond to some commands, understand simple words
say first word
13-16m say more than 5 words
16-19m understand “do not”
19-22m understand a question, repeat simple things others say
say 2 words in combination
22-25m understand in + under, say first sentence
influence of cultural soudns begins to have an impact on development of expressive language at
6-8m
when babbling sounds common
babbling
repeated creation of meaningless sounds that typically consist of 1 syllable
holophrase
one-word utterances that express a complete thought or phrase
telegraphic speech
creation of short phrases that convey meaning but lack some of the parts of speech that are necessary for a full + ceomplete sentence
arnd time of first words
joint attention
ability to direct teh attention of a social partner to objects or events and, in turn, follow their attention-directing gestures, suchas head-turning + pointing
by first birthday
10-50wrds
age 2 -> ~200wrds
vocabulary spurt after
18m
LAD (language aquisition device)
theoretical structure possessed by all humans taht prewires us to learn language + grammar rules
Noam Chomsky named it
2 physical parts of the brain involved in comprehension + production of speech
Wernicke’s + Broca’s areas
nature + nurture influence
language development
infant-directed speech
way of speaking to infants that is higher in pitch, simpler, + more repetitive than speech directed at adults or children. seems to be used automatically when in presence of an infant
interactionist approach
view of language learning taht stresses role of socialization
the more infants are talked to witht eh more diverse words, the quicker teh language learning + bigger vocabulary
sensation
physical reception of stimulation
perception
interpretation of stimulation that occurs in the higher processing centers of the brain
5 general receptor sites
retina of eye
cochlea in ear
olfactory membrane in nose
taste buds
skin
newborn visual acuity
20-120 to 20/240
must be 20ft from on object to see what a normal adult sees at 120-240ft
pull infant close to see them
newborn focal length
18-30cm
dist at which things can be clearly seen
distance betw nursing newborns + mother’s faces
by 1 year of ages, infants can see
like adults
Fantz visual preference paradigm
gather acuity info using this research technique
used lines
infant will chose one of 2 things to look at
ciliary muscles
small muscles of the eye taht work to move each eyeball + change shape of eye’s lens
2 primary issues affecting process of visual image processing
cliliary muscles not mature
vision center in brain is not fully developed
infants as young as 2 wks old can
discriminate betw colours
full colour percetion at 4months
- delayed bec cones ares till developing right after birth
cones
neurons in retina that respond to colour
immediately after birth newborns look at
contours of faces + objects
with age, infants begin to look at interior of objects
-adaptive change
humans begin hearing
before they are born
3-4 months before birth - ear fully formed + functional
infants begin moving eyes in direction of sounds at
4-6 months
what number of babies born have some degree of hearing loss or will develop early progressive childhood hearing loss?
4/1000 per yr
what helps babies find + latch onto mother’s breast for first time?
sense of smell
mother’s areola secrete a substance that smells like
amniotic fluid
what area of a newborn is especially sensitive to touch?
the face
ready to be stoked by the mother’s fingertips
newborns + infants thrive on this type of loving touch
the more they get the more they grow
what has been used with preterm _ low-brith-weight babies to promote growth _ development?
touch in form of massage
some of first studies of infant perception had to do with
depth perception
visual cliff
method used to examine infant depth perception using a patterned floor + pane of plexiglas over a deep drop
when infants willingly crawl over plexiglas, assumed they don’t perceive the depth
what is a potent painkiller in healthy newborns?
breastfeeding
during first 2 yrs, infants will receive on average vaccines for
14 diff illnesses
vaccine
substance taht is usually injected into a person to improve immunity against a particular disease
vaccine hesitancy
refusal or delay in immunization participation caused by concerns about vaccines
most effective interventions for improving child health
optimal infant + young child feeding practices
inadequate nutrition is associated with at least
35% of child deaths
likely won’t reach full developmental potential
nutrition
process of consuming carbohydrates, fats, proteins, + other elements in form of calories, to obtain energy + regulate body functions
optimal nutrition means
exclusive + on demand breastfeeding for first 6 months + introduction of complementary feeding + continued on-demand breastfeeding for min of 2 yrs
WHO
exclusive breastfeeding
when infants receive only breast milk, whether from breast or expressed, + on other liquides or solids including water
on-demand breastfeeding
nursing baby whenever baby shows signs of hunger durign day/night, such as crying or rooting, rather than a schedule
complementary feeding
process of consuming other foods + liquids along iwth breast milk to meet nutritional requirements of infants after 6 months
globally, what percet of infants under 6 months are breastfed exclusively?
35%
In canada ___% of infants under 6 months are breastfed exclusively?
26%
colostrum
yellowish, sticky breast milk that is secreted durign first 2-3 days after birth
colostrum benefits
full of WBC’s
antibodies perfectly suited for newbors
breast milk comes in after 4 days
milk is mature after
2 wks postpartum
first 2 wks sensitive period for establishing milk production
2 maternal hormones directly affecting breastfeeding
prolactin (milk production)
oxytocin (milk ejection)
durign first 2 sensitive wks of bresatfeeding…
more baby suckles, more stimulates nipple, more prolactin secreted, more milk produced
after first few wks, milk productio not so tied to prolactin secreted
infants who are not breastfed are…
10x times more likely to die in months following birth
diarrhea + pneumonia are
more frequent + severe in formula-fed infants
in developed nations, formula-fed infants are at risk for:
acute + chronic disorders
otitis media, meningitis, urinary tract infections, type 1 diabetes, + childhood leukemia
otitis media
infection of middle ear + common cause of earaches
breatfeeding also provides a protective role against…
obesity in later childhood + adolescence
the longer the child is breastfed, the lower the risk of obesity
breastfeeding helps
cognitive function
protect from obesity, cardiovascular illnesses later on, high blood pressure, problematic blood cholestrol levels
the longer they are breastfed - the greater the intelligence in late childhood + adulthood
breastfeeding benefits to mothers
right after birth - may reduce risk of postpartum hemorrhage/bleding
exclusive for 6 months can delay return of fertility + menstrual cycle/lactational amenorrhea
quicker return to pre-preg weight
lower rates of breast cancer + ovarian cancer
lactational amenorrhea
natural postpartum infertility that occurs when a woman is breastfeeding + her menstrual cycle hasn’t yet returned
health canada recommends
breastfeeding for 2+ yrs + introducing solid foods
maternal reasons to avoid breastfeeding
HIV infection
severe maternal illness
sepsis
taking of certain medications
chemotherapy drugs
what is the best feeding optino for preterm + very low-birth-weight infants?
breast milk
preterm
infant born before 32 wks gest
very low-birth-weight
infants < 1.5 kg at birth
international code of marketing of breast-milk substitutes
code adopted by Wolrd Heald Assembly to improve health of infants + children
malnutrition
deficiency of one + key nutrients (proteins, vitamins or minerals) that has a significant impact on energy + function of bodily systems
protein-energy malnutrition
most common cause of malnutrition
type of malnutrition in which insufficient food intake results in significant lack of protein + calories
lack of food/dietary imbalance
(kwashiorkor + marasmus common - significant poverty)
in canada usually poor nutrition (vitamins + minerals not extreme food deprivation)
what % of canadian children live in poverty?
just over 19%
40% of Canada’s indigenous children live in poverty
dominant western medical model of infant care says
infants should sleep separately from mothers + night wakings should be trated with variety of behavioural interventions like graduated extinction or controlled crying
solitary sleeping arrangements
role over/sufucate reason
medical model of infant care
dominant set of assumptions that guide provisiosn of infant care in west
graduated extinction
variety of sleep-training techniques where parents delay responding to infants’ cries for specified intervals of time, + respond only in a limited + prescribed way
co-sleeping
variety of shared sleeping arrangements where infant + caregiver sleep within sensory range of each other (same or separate surfaces) thereby permitting each to detect + respond to cues of the other
bedsharing
specific instance of co-sleeping where infant _ caregiver sleep together ins ame adult bed
in cultures where mothers + infants routinely breastfeed + co-sleep we find
lowest rates of SIDS
attachment
enduring emotional bond that connects 2 people across time + space
Sudden infant death syndrome
sudden + unexplained death, usually during sleep, seemingly healthy infant younger than 1yr
leading cause of death for canadian infants after congenital malformations, deaths associated with pregnancy + birther complications + fatalities attributed to prematurity + low birth weight
crip death + cot death
1/3000 babies
doesn’t wake up
aboriginals more at risk 3x higher
risk factors of SIDS
prone sleeping
maternal smoking during pregnancy
hot room
excessive blankets/pillows
premature birth
low birth-weight
second-hand smoke
(rates of sids dec)
SIDS greatly reduced by
breastfeeding
