PSYCH211 Study Guide - Midterm Guide: Dwarfism, Reticular Formation

74 views25 pages
Published on 16 Oct 2011
Department
Course
Professor
Chapter Notes – PSYCH 211
Chapter 8
Body Growth
- by age 5, body proportions are similar to those of adults
- depending on culture, we should not view short stature as a sign of
problems with growth or health
Skeletal Growth
- between ages 2 and 6, there are appx. 45 new epiphyses - where cartilage
hardens into bone
- x-ray of growth centers enable doctors to estimate children’s skeletal age;
can be helpful in diagnosing growth disorders
- end of preschool years - children start losing their baby teeth; can depend
on genetics, nutritional factors
- diseased baby teeth can affect the health of permanent teeth
- another factor for teeth is protection from exposure to tobacco smoke which
suppresses children’s immune system, including ability to fight bacteria
Brain Development
- age 2-6 - brain increases from 70% of its adult weight to 90%; also
undergoes reshaping and refining
- overabundance of synaptic connections supports plasticity; synaptic pruning
then follows
- rapid growth of frontal lobe from 3-6 yrs (attention and planning behavior),
and also left hemisphere activity
- right hemisphere activity increases steadily throughout early and middle
childhood, with spurt between 8-10
- synaptic density rises during the first three years, then falls to adult level
around 10
Differences in rate of development between two hemispheres suggest they
are continuing to lateralize
Handedness
- by end of first year children show a hand preference
- handedness reflects the greater capacity of one side of the brain -
individual’s dominant cerebral hemisphere - to carry out skilled motor
action
- 90% right handed
- brains of left handers tend to be less strongly lateralized then those of right-
handers
- many left handers are ambidextrous
- prenatal events may profoundly affect handedness; twins are more likely
than ordinary siblings to differ in hand preference, most likely because twins
usually lie in opposite orientations in the uterus
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 25 pages and 3 million more documents.

Already have an account? Log in
- newborns’ bias in head position causes them to spend more time looking at
and using one hand
- most left-handers have no developmental problems; may actually have
some advantages
Other Advances in Brain Development
- at rear and base of brain - cerebellum - structure that aids in balance and
control of body movement
- fibers linking cerebellum to the cerebral cortex grow and myelin ate from
birth through preschool years; contributes to dramatic gains in motor
coordination
- these connections also support thinking
- the reticular formation - maintains alertness and consciousness,
generates synapses, and myelinates throughout early childhood and into
adolescence; neurons send out fibers to other areas of the brain, many of
which go to frontal lobes and aid in controlled attention
- hippocampus - plays vital role in memory and in images of space -
undergoes rapid formation of synapses and myelination in the second half of
the first year; also makes connections with frontal lobes and aids with
dramatic gains in memory and spatial understanding
- corpus callosum - large bundle of fibers that connects the two
hemispheres; supports smooth coordination of movements on both sides of
the body, and integration of many aspects of thinking; the more complex the
task, the more critical the communication
- production of synapses and myelination increase at 1 year, peak between 3
and 6, and continue at a slower pace through middle childhood and teens
Influences on Physical Growth and Health
Heredity and Hormones
- genes influence growth by controlling the body’s production of hormones
- the pituitary gland - located at base of brain and plays critical role by
releasing two hormones that induce growth - GH and TSH
- growth hormone (GH) - necessary from birth on for development of all
body tissues except CNS and genitals
- synthetic GH has been used in attempt to treat short normal-GH children
but they grow only slightly taller; those however that lack GH grow
significantly more when treated
- thyroid-stimulating hormone (TSH) prompts thyroid gland in neck to
release thyroxin, which is necessary for brain development; infants born with
a deficiency must receive it at once, or they will be mentally retarded
Emotional Well-Being
- extreme emotional deprivation can interfere with production of GH and lead
to psychosocial dwarfism - growth disorder that occurs between 2 and 15
yrs - short stature, decreased GH, immature skeletal age and serious
adjustment problems
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 25 pages and 3 million more documents.

Already have an account? Log in
- if treatment is delayed, dwarfism can be permanent
Sleep Habits and Problems
- GH is released during the child’s sleeping hours
- total sleep declines in early childhood; most stop napping between ages 3
and 4 although in some cultures persists through adulthood
- co sleeping is not associated with problems during preschool years
- preschoolers have trouble differentiating fantasy and reality, and
nightmares are common (50%), sleepwalkers (4%), and sleep terrors (3%)
Nutrition
- Appetite tends to become unpredictable
oMany become picky eaters
oAppetites decline because their growth has slowed
- Preschoolers need a high-quality diet, including same foods adults
need but in different amounts
oFats, oils, salts should be kept to a minimum because of their
link to high blood pressure and heart disease in adulthood
- Tend to imitate food choices of those they admire
- Adding sugar or salt in hopes of increasing a child’s willingness to eat
healthy foods simply strengthens the child’s desire for a sugary or salty
taste
- Milk avoiders are shorter in stature and have a lower bone density
- Offering bribes causes children to like the healthy food less and the
treat more
- Too much parental control limits their opportunities to develop self-
control
- A nutritionally deficient diet is associated with attention difficulties,
poor mental test scores, behavior problems
oEven after family factors that might account for these
relationships are controlled
Infectious Disease
- When children are undernourished, disease interacts with malnutrition
in a vicious spiral, with potentially severe consequences
Infectious disease and malnutrition
- Disease is a major contributor to malnutrition
- Developmental impairments and deaths due to diarrhea can be
prevented with nearly cost-free oral rehydration therapy (ORT);
supplements of zinc also help for immune system functioning
Immunization
- 20% of American infants and toddlers are not fully immunized
- Childhood illness rises with child-care attendance
Childhood Injuries
- Unintentional injuries are the leading causes of childhood mortality in
Unlock document

This preview shows pages 1-3 of the document.
Unlock all 25 pages and 3 million more documents.

Already have an account? Log in

Document Summary

By age 5, body proportions are similar to those of adults. Depending on culture, we should not view short stature as a sign of problems with growth or health. Between ages 2 and 6, there are appx. 45 new epiphyses - where cartilage hardens into bone. X-ray of growth centers enable doctors to estimate children"s skeletal age; can be helpful in diagnosing growth disorders. End of preschool years - children start losing their baby teeth; can depend on genetics, nutritional factors. Diseased baby teeth can affect the health of permanent teeth. Another factor for teeth is protection from exposure to tobacco smoke which suppresses children"s immune system, including ability to fight bacteria. Age 2-6 - brain increases from 70% of its adult weight to 90%; also undergoes reshaping and refining. Overabundance of synaptic connections supports plasticity; synaptic pruning then follows. Rapid growth of frontal lobe from 3-6 yrs (attention and planning behavior), and also left hemisphere activity.

Get OneClass Grade+

Unlimited access to all notes and study guides.

YearlyMost Popular
75% OFF
$9.98/m
Monthly
$39.98/m
Single doc
$39.98

or

You will be charged $119.76 upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.