Physical Development in Early Childhood
Gross motor development
As childrens bodies become more streamlined and less top-heavy, their center of gravity shifts downward, toward the trunk and balance improves. By age 2 preschoolers' gait becomes smooth and rhythmic.
Cultural growth differences
Asain-indian children smaller
Sleep difficulties
Associated with impaired cognitive performant, including decreased attention, speed of thinking, working memory and intelligence and achievement test scores, as well as with internalizing and externalizing problems. Electronics trouble children when falling asleep, mismatch between parental demands, family turmoil. Nightmares are very common Sleepwalkers common Sleep terrors Many sleep disorders of early childhood subside without treatment, although some might need medical or psychological eval.
Napping
Remains common among africans, asian, and hispanic children throughout the day and they sleep less at night time. American children stop napping or nap less around the age 3&4.
Effective eating strategies
Repeated, unpressured exposure to a new food
Sleep problems
Result from inadequate parental control over young children's TV, computer and video games. May also stem from a mismatch between parental demands and childrens biology.
fMRI Evidence
Reveals that energy metabolism in the cerebral cortex reaches a peak around this age (4-5)
Self-help skills
two year olds put off and on simple clothes three years children can dress and undress well enough to take care of toileting needs ages 4&5 children can dress w/ no supervision
GH deficiency
2% suffer from deficiencies. W/O medical intervention, such children reach an average mature height of only 4-4.5 feet. When trr
Average North American Boy
5 year old 43 inches tall and weights 42 pounds
Skeletal Growth
Between ages 2 and 6 approximately 45 new epiphyses, or growth centers in which cartilage hardens into bone, emerge in various parts of the skeleton. X-rays of these growth centers enable doctors to estimate childrens skeletal age or progress towards physical maturity.
Brain Growth
Between ages 2-6 the brain increase from 70 percent of its adult weight to 90 percent. Physical coordination, perception, attention, memory, language, logical thinking, and imagination improve.
Sex differences
Boys are ahead of girls in skills that emphasize force and power. -By age 5 they can jump father and run faster and throw a ball farther.. Girls have an edge in fine motor skills and in certain gross motor skills that require good balance and foot movement, such as hopping and skipping Boys can throw a ball father than girls only when using their dominant hand. when using nondominant hand, the sex difference is minimal.
Immunization
Childhood diseases have declined dramatically for this reason.
Dynamic Systems
During preschool years, children continue to integrate previously acquired skills into more complex dynamic systems.
Factors related to Childhood injuries
Ecological System- Individual, family, community and societal influences Boys are twice as likely as girls to be injured due to their higher activity and greater impulsivity and risk taking. Children with certain temperamental characteristics- inattentiveness, over-acitivity, irritability, defiance and aggression are at greater risk. These children are more likely to protest to doing "safer" things. Poverty, single parent hood and low parental education Broad societal conditions, in developing countries, the rate of death from injury before age 15 is 5 times as high as in developed nations.
Zinc Supplements
Essential for immune system functioning -reduces the incidence of severe and prolonged diarrhea, especially when combined with ORT Through these interventions, the lives of millions are saved each year.
Childhood rates of injury in the US
Extensive poverty, shortages of high-quality child care and high rate of birth to teenagers who are not ready for parenthood.
Psychosocial Dwarfism
Extreme emotional deprivation can lead to this. -It is a growth disorder that appears between the ages of 2 and 15. Characteristics include, decreased secretion of GH and melatonin, a hormone within the brain that promotes sleep (during which GH is released), very short stature and immature skeleton age. -Also display serious adjustment problems, which help distinguish psychosocial dwarfism from normal shortness.
Loosing teeth
Girls who are ahead of boys in physical development , lose their primary teeth sooner. Cultural ancestry also make a difference. North American children typically get their first secondary (permanent) tooth at 6.5 years. Children at just over 5 years in Ghana and Hong Kong get it around their 6th bday.
Dominant Cerebral Hemisphere
Handedness reflects the greater capacity of one side of the brain to carry out skilled motor action.
Low SES children
Impact of disrupted sleep on cognitive functioning and emotional adjustment is more pronounced.
Areas of the brain during rapid growth
In addition to increasing in weight, the brain undergoes reshaping and refining. Age 4-5, many parts of the cerebral cortex have overproduced synapses. In some regions, such as the prefrontal cortex, the number of synapses is nearly double the adult value.
Left hemisphere
Language skill, and support childrens increasing control over behavior, also mediated by the prefrontal cortex.
Corpus Callosum
Large bundle of fibers connective two cerebral hemispheres. Production of synapses and myelination of the corpus callosum increase at 1 year, peak between 3-6 years and continue at a slower pace through the middle childhood and adolescence. Supports smooth coordination of movements on both sides and integration of thinking, perceptions, attention, memory, language and problem solving.
Immunization and Autism
Many parents have been influenced by media reports suggesting a link between mercury-based preservative used for decades in vaccines and a ride in the number of children diagnosed with autism. -Large scale studies show NO consistent effects on cognitive performance.
Parents facilitating preschoolers' motor development
Many western parents provide them with early training in gymnastics, tumbling, dance, soccer and other movement skills through organized classes. These formal lessens are helpful for exercise and social interaction but add little impact on gross motor progression. Children master the gross-motor skills of childhood through everyday play Physical environment in which play takes place and affect mastery of complex motor skills
Oral rehydration therapy
Most developmental impairments and deaths due to diarrhea can be prevented with this and is usually cost free. -Sick children are given glucose, salt, and water solution that quickly replaces fluids the body loses.
TSH deficiency
Must receive it at once or they will be intellectually disabled. -Once the most rapid period of brain development is complete, children with too little thyroxine grow at a below-average rate, but the CNS is no longer affected/ Children with prompt treatment, catch up in body growth and eventually reach normal size.
Growth Hormone
Necessary from birth on for development of almost all body tissues. -Stimulates the liver and epiphyses of the skeleton to release another hormone called insulin-like growth factor 1 (IGF-1), which triggers cell duplication throughout the body, especially the skeleton, muscles, nerves, bone marrow (origin of blood cells), liver, kidney, skin, and lungs.
Synaptic Pruning follows
Neurons that are seldom stimulated lose their connective fibers, and the number of synapses is reduced. By age 8 to 10, energy consumption of most cortical regions diminishes to near-adult levels.
Plasticity
Overabundance of synaptic connections supports plasticity of the young brain, helping to ensure that the child will acquire certain abilities even if some areas are damaged.
Uneffective eating strategies
Parents who are worried about their childs eating can be unpleasent and stressful Restricting access to certain foods increases childs desire to ear them. More a mother pressures, more underweight the child usaully is And the more resticting parent the more overweight a child is
Hippocampus
Plays a vital role in memory and in images of space that help us find our way, undergoes rapid synapse formation and myelination in the second half of the first year, when recall memory and independent movement emerge. Changes to these structures through lateralization give the ability to use strategies to store and retrieve info, expansion of autobiographical memory and drawing and reading of maps.
Infectious diseases and malnutrition
Poor diet depresses the body's immune system, making children more susceptible to disease Disease is a major contributor to malnutrition, hindering physical growth and cognitive development. Ilness reduces appetite and limits the body's ability to absorb foods, espically intestinal infections.
Declines in appetite
Preschooler's appetites decline because their growth has slowed. - wariness of new foods is also adaptive: if they stick to familiar foods, they are less likely to swallow dangerous substances when adults are not around to protect them,
Ball skills
Preschoolers- Stand still, face the target and throw their arm thrust forward. catching is awkward as well. 5-6 years- They begin shifting their weight to a rear foot in a prepping back swing, then then rotating their trunk and stepping & throwing the ball at once.
Thyroid-simulating hormone (TSH)
Prompts the thyroid glad in the neck to release thyroxine, which is necessary for brain development and for GH to have its full impact on body size.
Body Growth during early childhood
Rapid increase in body size of the first two years tapers off into a slower growth pattern. -On average, 2-3 inches in height and about 5 pounds in weight each year. -Boys slightly larger than girls -Baby fat that began to decline in toddlerhood drops off further, children gradually become thinner, girls retain more fat and guys more muscular. By age 5, top-heavy, bowlegged, potbellied toddler has become more streamlined, flat- tummies, longer-legged child with body proportions similar to those of adults. Posture and balance improve
Drawing Progression
Scribbles First representation forms -Scribbles start to become pictures -Major milestone in drawing when children use lines to represent boundaries of objects. Realistic Drawings -Drawings contain more conventional human and animal figures with the head and body differentiated. -Use of depth cues such as overlapping objects, diagonal placement and converging lines
Right hemisphere
Spacial skills, such as giving directions, drawing pictures, and recognizing geometric shapes, develops gradually over childhood and adolescence.
Lateralization
Specialize in function
Reticular Formation
Structure in the brain stem that maintains alertness and consciousness, generates synapses and myelinates throughout early childhood into adolescence. Neurons send out fibers to other areas of the brain. and many go to prefrontal cortex, contributing to improvements in sustained, controlled attention.
Cerebellum
Structure that aids in balance and control of body movements. Fibers linking the cerebellum to the cerebral cortex grow and myelinate from birth through the preschool years and contributes to dramatic gains in motor coordination. Damage to cerebellum leads to motor and cognitive deficits, including problems with memory, planning and language
Handedness
Supports the joint contribution of nature and nurture to brain lateralization As early as the tenth prenatal week, most fetuses show a right-hand preference during thumb-sucking. by 6th months, infants display a smoother, more efficient movement when reaching with their right arm rather than their left.
Fine motor skills
To parents, fine-motor progress is most apparent in 1. Children's care of their own bodies and 2. drawings and paintings that fill walls at home. Control of hands and fingers improve.
Sleep
Total sleep declines in early childhood -2 and 3 year olds sleep 11-12 hours -4 and 6 year olds sleep 10-11 hours
Efe of the republic of congo
Typical adult height is less than 5 feet. -Genetic reasons, the impact of hormones controlling body size reduced By age 5, the average Efe child is shorter than more than 97 percent of North American and European 5 year olds and reach puberty and stop growing at a younger age. others suggest that their small size reduces their caloric requirements in the face of food scarcity in the rain forest underbrush, and still others think that it enables earlier childbearing to compensate fro the Efe's high mortality rate.
Leading cause of death during early/middle childhood years
Unintentional injuries are the leading cause of childhood mortality in industrialized nations. Auto/traffic accidents, drownings, and burns are the most common childhood injuries. Motor collisions are most frequent and rank as the second leading cause of death from birth to age 5 (after suffocation among infants drowning) and the leading cause among school-aged and adolescents.
Sleeping arrangements of US 3 year olds
White presschoolers are less likely to cosleep with their parents than african or hispanics. White children tend to go to bed with a security object, which may help them adjust to the feelings of uneasiness at being left by themselves in the darkened room -AA are likely to share a bedroom with siblings. By 6 or 7 western cosleeping children usually ask to sleep in their own bed.
Individual Differences
Wide differences exist in the ages at which children reach motor milestones. -A tall, muscular body tends to move more quickly and to acquire certain skills earlier than a short, stocky youngster.
The National Association for Sport and Physical Education
recommends that preschoolers engage in at least 60 minutes of adult-planned physical experiences in which parents and teachers provide enjoyable games and other playful activities, and up to several hours of child-directed physical activity, every day. Preschoolers cannot easily acquire to new motor skills
EEG, NIRS and fMRI
reveal rapid growth from early to middle childhood in prefrontal-cortical areas devoted to various aspects of executive function. These include inhibition of impulses, attention, working memory, and planning and organizing behavior. Left cerebral hemisphere is especially active between 3 and 6 years and then levels off. -In contrast, activity in the right hemisphere increases steadily throughout early and middle childhood, with a slight spurt between ages 8 and 10.
Handedness in Western nations
right handed people- 90% of the pop., language is housed in the left hemisphere with hand control. Left handed- 10%, language is usually associated on the right side, or more often shared between the two. AKA brains of left handers are less strongly laterized than those of right-handers many left handers are ambidextrous
