Infancy and brain development Flashcards
(42 cards)
Describe evidence to indicate what sense(s) are well developed at birth
Hearing, taste, smell well developed at birth, evidence: Infants come equipped for prenatal learning: DeCasper& Spence (1986):Mothers who were 7.5 months pregnant were asked to read 1 of 36 stories a day.16 infants were tested at 56 hours old. IBI=interburst intervals(IBIs)
Half of babies were rewarded(with familiar story) when increased IBI, half were rewarded(with familiar story) when decreased IBI
Findings:-infants responded to reinforcement, wanted to hear the familiar store
-Shows the infants can hear prior to birth
DeCasper & Fifer(1980):
Participants were babies that were less than three days old, they sucked on dummies while the mother/non-mother reads Dr. Suess,
Findings:
-Babies changed their IBI to hear their mother’s voice, they had a positive preference for the maternal voice and a negative preference for the non-maternal voice
Temperament in ___ is more influenced by heredity than temperament in_____
childhood; infancy
True or false, boys and girls differ in their reaching of motor milestones(e.g, sitting, crawling, walking, running, jumping)
false
Prison in NZ/UK?U.S are comparable to a_____ parenting style, whereas Norwegian prisons are comparable to a ______ parenting style
Authoritarian, authoritative
True or false, spanking is not associated with any negative child outcomes
False
“Practice is important for processing speed”. Who is most likely to have said this?
Robbie Case
Newborn infants change their pattern of sucking when:
Listening to their mother’s voice
Describe
evidence as to what sense(s) are not well developed at birth.
Visio develops more slowly, acuity: using preferential looking technique(when an infant habituates to a stimulus and then is introduced with another novel stimulus, they will look at the second stimulus for longer)
-This showcases a newborn’s ability to discriminate between stimuli
-Newborns focus best when objects are 30cm away from them
-Visual acuity is adult-like by 6-8 months
Colour perception:
1month:red&green cones in place
2 months:colour discrimination
4 months:categorical colour perception
Depth perception:
-Different cues are used to perceive depth
-Infants using most cues(6-7 months)
How do limitations in sensory development and physical development impair initial development, and what related changes facilitate development?
Infants initially have a very limited physical ability
-1-3 months: arm moves in direction of object, but hand grasp occurs too early, baby swipes at objects
-3-4 months: arm moves towards and grasps objects
-7-8 months-crawling
-1 year:walking
How is a human infant’s brain immature, and what developments take place in the brain over the first two decades of life?
The human brain is very immature at birth(28% or adult weight) compared to a chimp’s brain and takes a longer time to mature(3 years to reach 70% of adult weight)
-Brains increase in size/weight because neurons grow larger and increase their connections(synaptogenesis)
Glial cells: help form myelin, outnumber neurons by 9 to 1(50 to 1 in an adult brain)
There is a curvilinear trend in synaptic density
(where synaptic density is high at 6yrs of age and then declines until 14yrs of age)
How does experience in the world affect brain development? Give examples.
Example 1: Correction for strabismus(crossed eyes/squint) must occur before 6 years of age so that synapses linking the less favoured eye to the brain will remain.
-Initial overproduction of synapses
-Synaptic pruning, guided by experience, results in efficient, trained brain
Example 2: Phoneme perception
-Baby sounds: are the same for 6 months olds regardless of the language the baby is learning
-Afterwards, sounds take on a different form depending on what language the baby is learning
-perceptual narrowing: a developmental process during which the brain uses environmental experiences to shape perceptual abilities
-Infants can selectively discriminate among native phonemes, whereas discrimination of phonemes to which they are not exposed declines
Example 3: Emotional closeness(example of children of severely depressed mothers)
-Stress elevates cortisol levels, which in turn interferes with neural development
- Children who receive sensitive and nurturing care in their first year are less likely than other children to respond to minor stresses by producing cortisol(provides protection)
How is the brain “primed for learning” early in development, and why is it less primed later in life?
-Great synaptic density, allowing for rapid learning
-5 weeks of age: Glucose( which fuels the brain) utilisation is highest in the sensorimotor cortex, thalamus, brainstem and cerebellum(low rate in cerebral cortex)
-Patterns of glucose utilisation begins to resemble adulthood as early as 8 months and typically 1 yr
-Adult rates are more evident by 2 yrs of age but the glucose metabolic rate continues to increase until approx.9yrs of age
-After 9 yrs it begins to decline and will reach adult values again in the latter part of the second decade of life
-A decrease in glucose metabolic rate in the adult might reflect a “pruning” of excessive neuronal connectivity
Describe the changes that take place during the period of adolescence. What account for these changes?
Areas of greatest development during adolescence
-Prefrontal cortex
-corpus callosum
-cerebellum
Adolescence is a time of “fewer but faster”neural connections
How does the schedule for vision affect human development?
Because the vision is main way of seeing world, it slows down the development.
What does this schedule for the development of physical ability mean for human development?
if can’t move around, you can’t explore the environment
Why is the human brain so immature at birth?
The head will be too big
What does an immature brain mean for human development?
human development is really slow
What the implications of these aspects of brain development?(connections elaborate themselves through interactions with the world)?
it indicates that the early childhood is important to later adulthood
What abilities is the cerebral cortex responsible for ?
language, executive functions, thinking and planning, higher order things
So what does that imply about development?
It changes in major ways implies the development is very slow
Are early experience important? What do they affect?
Yes, affect brain development and child’s emotional wellbeing
What factors of environment affect the brain
Nourishment, care, surroundings
what is believed to play a role in this trend of puberty?
nutrition
What is the new idea adapted from old idea? (Experiences before 3 yrs have limited impact)
Early experiences influence the architecture of the brain and the nature and extent of adult capacities.
