lifespan physical development feldman: module 3-1
TRANSCRIPT
NORMAL GROWTH
Growth occurs in a cephalocaudal (head to tail) pattern
The head takes up one-fourth of total body length at birth, but only one-fifth at age 2.
Growth occurs in a proximodistal (near to far) pattern.
The head, chest and trunk precede the limbs and extremities.
BODY GROWTH IN INFANCY
Average North American newborn weight 7 ½ pounds and is 20 inches long.
Birth weight triples in one year and quadruples by the end of two years.
By the second year, the child is at 1/5 of its adult weight (30 lbs.) and ½ its adult height (30 + inches).
Muscle tissue increases very slowly.
2-3 inches per year
5 pounds per year
Baby fat declines
Posture and balance improve due to lower center of gravity.
2-3 inches per year
5 pounds per year
Bones harden (skeletal age), lengthen and broaden
ligaments are not yet firmly attached.
Improved strength and muscle tone.
Primary teeth are replaced with permanent teeth
FACTS ABOUT PHYSICAL GROWTH
EARLY CHILDHOOD MIDDLE CHILDHOOD
BODY GROWTH AND GENDERGirls are shorter and lighter and have a higher ratio of body fat to muscle than boys.
Children differ in the rate of physical growth.
Skeletal age is the best way to estimate the child’s physical maturity.
African Americans mature faster than Caucasians and girls mature faster than boys.
.Gross motor development involves large muscle groups and activities that generally have to do with locomotion
Fine motor development involves smaller muscle groups and activities such as reaching and grasping
MOTOR DEVELOPMENT
PERSPECTIVES ON MOTOR DEVELOPMENT
Nature-focused view: Developmental maturation
Nurture-focused view: Dynamic systems theory: the child develops new motor skills by
adapting and adding to old ones to meet his/her goals
DYNAMIC SYSTEMS THEORY OF MOTOR DEVELOPMENT
Mastery of motor skills involves acquiring increasingly complex systems of action.
Each new skill is a joint product of: 1) Central nervous system development 2) movement capacities of the body 3) goals of the child 4) environmental supports for the skill
Gross motor development follows a generally universal sequence.
Cephalocaudal and proximodistal trends are evident.
There is no fixed maturational timetable.
GROSS MOTOR DEVELOPMENT
Iranian orphans are not encouraged to move
Indians in Southern Mexico are discouraged from walking
Kipsigi parents in Kenya encourage motor skills and children walk early
CULTURAL VARIATIONS IN MOTOR DEVELOPMENT
GROSS MOTOR - PRESCHOOL
Age 3 – hop, jump, run for the fun of it
Ages 4 and 5 – more adventurous, climb
USING COMMON SENSE
For adequate motor development, preschoolers need places and opportunities to play
There is no evidence that formal lessons facilitate development
Pushing the child may undermine self confidence
GROSS MOTOR – SCHOOL CHILDREN
Skipping rope, swimming, bike-riding, skating
10-11 year olds can learn from sports
Gain greater control over muscles
Boys outperform girls
Need opportunities for physical play
ORGANIZED SPORTS IN CHILDHOOD - POSITIVES
Opportunities for exercise
Learning to compete
Opportunities for peer, friendship relationships
Reduces tendency for obesity
ORGANIZED SPORTS IN CHILDHOOD - NEGATIVES
Negatives
Too much pressure to perform Physical injuries Distraction from academic work Unrealistic expectations as an athlete Wrong values Possible exploitation
GROSS MOTOR - ADULTHOOD
Gross motor skills improve in adolescence
They peak in the 20’s
They decline through the remainder of adulthood
Newborns pre-reach (drops out about 7 weeks)
Voluntary reaching appears at about 3 months
By 4-6 months an infant can grasp an object in a darkened room.
By 7 months they can use one arm
INFANCY - SEQUENCE OF REACHING BEHAVIOR
Newborn grasping reflex
palmar grasp – can be varied
4-5 months, transfer objects from hand to hand1 year – pincer grasp
(Trying to push infants beyond their readiness may backfire.)
SEQUENCE OF GRASPING BEHAVIOR
Reaching affects cognitive development because it opens up new ways of exploring the environment.
Infants use proprioceptive cues to reach as early as 4 months
FINE MOTOR SKILLS - INFANCY
REACHING & GRASPING IN INFANCY
Perceptual-motor coupling is usedsense of touchsense of vision by 8 months
Experience plays a role in development
Pincer grasp goes with crawling & children pick up things from floor.
FINE MOTOR – EARLY CHILDHOOD
Fine motor progress is apparent in
Children’s care of their own bodiesDrawing and painting
SELF-HELP SKILLS
2-3 yearszips, puts on clothes3-4 yearsbutton (large buttons)5-6 yearsties shoes
2-3 yearsuses spoon3-4 yearsserves self food4-5 yearsuses fork5-6 yearsuses knife
DRAWING AND PAINTING
3-4 yearscopies vertical line/circleDraws a “tadpole” person
4-5 yearsCuts with scissorsCopies triangle, cross, some letters
5-6 yearsDraws person with 6 partsCopies some numbers, simple words
FINE MOTOR – MIDDLE CHILDHOOD
Increased myelination of CNS
6-year-olds can hammer, paste, tie shoes, fasten clothes
7 years – use pencil & print smaller
8-10 years – write cursive & use hands independently
12 years – approach adult skill levels
Girls outperform boys
FINE MOTOR – OLDER ADULTHOOD
Slower motor behavior
Neural noise – irregular neural activity in the CNS
Strategy – may have to slow to perform accurately
Can learn new motor tasks, but more practice required
HANDEDNESS
Seems to have a genetic influence
Correlates to thumb-sucking before birth & direction of head-turning after birth
Right-handedness is dominant (9:1) in all cultures
HANDEDNESS
10% of left-handers process speech in the right hemisphere and 15% across both hemispheres.
Left handers are more likely to have reading problems.
They also have very good visual-spatial skills .
They tend to be intelligent.
INFLUENCES ON PHYSICAL GROWTH & HEALTH
Genetics
Infectious disease
Childhood injuries
Hormones
Emotional well-being
Nutrition
CHILDREN’S HEALTH - PREVENTION
Immunization Meningitis, measles, rubella, mumps, chicken pox, polio
Accidents Poisonings, falls, drowning, choking
Poverty Good medical care, nutrition, living conditions
INFLUENCES ON PHYSICAL GROWTH & HEALTH - IMMUNIZATION
Immunization has caused a dramatic decline in childhood diseases in the industrialized world
24% of American preschoolers lack essential immunizations (40% in poverty)
Availability of careMisconceptions (MMR & autism)
INFLUENCES ON PHYSICAL GROWTH & HEALTH – PITUITARY GROWTH HORMONES
Growth hormone (GH) needed for development of all body tissues except CNS & genitals
Thyroid-stimulating hormone (TSH) causes the thyroid gland to release thyroxin, needed for normal nerve cell development and for GH to have a full impact on body size
INFLUENCES ON PHYSICAL GROWTH & HEALTH – EMOTIONAL WELL BEING
Psychosocial dwarfismCaused by extreme emotional deprivationAppears between 2 & 15 years of ageCan interfere with the production of GHVery short stature Immature skeletal ageSevere adjustment problemsCan be treated
DEFINITION OF ADOLESCENCE
Transition between childhood and adulthood
Physically begins with puberty
Culturally defined; ends gradually with assumption of adult responsibilities.
Lasts nearly a decade (or more) in the U.S.; culturally exaggerated due to education
THE GROWTH SPURT OF PUBERTY
Most rapid growth since infancy
Average of age 9 for girls; 11 for boys
Girls grow 3.5 inches/year; boys 4 inches
50% of body weight gained in adolescence
Also changes in leg length and facial structure
WHY DOES PUBERTY HAPPEN EARLIER THAN IT USED TO?
Nutrition ? – Better than in earlier times
Hormones ? – Found in food supply
Stress ?Fat ?
STRESS THEORY OF EARLY PUBERTY
Hypothalamus pituitary sex glands produce gonadotrophinsAndrogens (testosterone)Estrogens (estradiol)
Pituitary thyroid gland produces growth hormone
Cortisol (stress hormone) may trigger early onset (pituitary activity)
FAT THEORY OF EARLY PUBERTY
Weight affects the timing of menarche (106 +/- 3 pounds)
Athletes and anorexics become amenorrheic
Fat and leptin may also be influential
NORMAL PHYSICAL DEVELOPMENT:EARLY & MIDDLE ADULTHOOD
Early Adulthood, peak muscle tone & joint function
Senescence
Middle Adulthood – gradual changes,lose height, gain weight, in 40s & 50s skin sags, wrinkles, age spots, hair thins, thicker finger- and toenails, yellow teeth
CHANGES IN MIDDLE ADULTHOOD (CONT’D)
Sarcopenia – age-related loss of muscle mass & strength
Lose 1-2% per year starting at age 50
Exercise can help to reduce this loss
Also lose bone from the late 30’s; this accelerates in the 50’s
CHANGES IN MIDDLE ADULTHOODCholesterol increasesLDL – leads to atherosclerosis
Blood Pressure increases; sharply for women at menopause
Metabolic disorder – hypertension, obesity, insulin resistance, high cholesterol, low HDL, weight gain (Part of normal aging?); weight loss & exercise help
Lungs become less elastic
ADULT HEALTH - REPRODUCTIVE SYSTEM
The 20’s are ideal for reproduction. Risks of miscarriage and chromosomal disorders are reduced.
First births to women in their 30’s have increased in the past two decades
Dramatic rise in fertility problems in the mid-thirties (14 to 26%)
CHANGES IN MIDDLE ADULTHOOD - SEXUALITY
Climacteric – loss of fertility
Menopause – ceasing of menstrual cycles (average age 52)
Drop in estrogen, hot flashes, nausea, fatigue, rapid heartbeat
Gradual decline for men (no andropause)
ADULT HEALTH IMMUNE SYSTEM
Capacity declines after age 20, partially due to thymus and inability to produce mature T cells
Stress and depression can also weaken the immune system
ADULT HEALTH - STATES OF MIND
Western stereotype: deterioration is inevitable
In one study, people with positive self-perceptions of aging live 7 ½ years longer
More optimistic elders are about capacity to cope with physical challenge, better they are at overcoming threats to health
Low SES elders are less likely to believe they can control their health, to seek medical treatment, or to follow doctors’ orders.
BIOLOGICAL THEORIES OF AGINGCellular clock (Hayflick) 70-80 cell divisions, based on telomeres 120-year lifespan
Free-radical Calorie restriction antioxidants
Mitochondrial Cellular energy producers Linked to free radical theory
Hormonal Stress hypothalamic-pituitary-adrenal axis Stress & decline in immune function
INFLUENCES ON PHYSICAL GROWTH & HEALTH – INFECTIOUS DISEASES
70% of deaths in children under age 5 are due to infectious diseases
99% are in developing countries and are related to malnutrition
Most death due to diarrhea can be prevented by oral rehydration therapy (ORH)
CHILDREN’S HEALTH - PREVENTION
Immunization Meningitis, measles, rubella, mumps, chicken pox, polio
Accidents Poisonings, falls, drowning, choking
Poverty Good medical care, nutrition, living conditions
INFLUENCES ON PHYSICAL GROWTH & HEALTH - IMMUNIZATIONImmunization has caused a dramatic decline in childhood diseases in
the industrialized world
24% of American preschoolers lack essential immunizations (40% in poverty)
Availability of care Misconceptions (MMR & autism)
INFLUENCES ON PHYSICAL GROWTH & HEALTH – OTITIS MEDIA70+% of American children have had at least one bout by age 3
Xylitol may be a preventative
Tubes remain controversial
Child-care settings should control infection
May cause problems in language development due to hearing problems
HEALTH - MIDDLE TO LATE CHILDHOOD
This is generally a healthy time
The most common vision problem (25%) is myopia (nearsightedness), which progresses more rapidly during the school year.
Otitis media becomes less prevalent.
ASTHMA
19% of N.A. children have chronic diseases and conditions
Asthma accounts for 1/3 of chronic illness and is the most common reason fro school absence
Incidence has increased dramatically, 8% of U.S. children—boys, low SES, parents smoke, born underweight most at risk
INJURIES IN EARLY CHILDHOOD
Leading cause of childhood mortality in industrialized countries.
Motor vehicle collisions are the most frequent source of injury at all ages & the leading cause of death among children over 1 year old
Auto accidents, drownings and burns are the most common accidents of early childhood
INJURIES IN MIDDLES TO LATE CHILDHOODThe rate of injury fatalities increases into adolescence with rates for
boys rising considerably above those for girls.
MV accidents are still the leading cause of death, with bicycle accidents next.
Parents often overestimate children’s safety knowledge and behavior
OBESITY: U. S. & WESTERN NATIONS
There has been a marked rise in obesity in the U.S. and other Western nations. Percentage doubled since 1980;
quadrupled since 1965
U.S. may have 2nd highest rate
15% of U.S. children 6-11 overweight
Less common in African American than white children; trend reverses in adolescence
CAUSES OF OBESITYGenetics
SES (diet); high fat, low-cost foods
Family stress (comfort food)
Pastimes (TV, videogames) and lack of exercise
Fast-food and busy schedules
Learned food preferences (school cafeterias)
MIDDLE ADULTHOOD: ILLNESS & DISABILITY
Cancer & cardiovascular disease are the leading causes of death. Cancer alone among women.
Motor vehicle collisions decline, falls resulting in fractures & death nearly double.
Personality traits that magnify stress, especially hostility and anger, are serious threats to health.
CARDIOVASCULAR DISEASE
First detected factors may be high blood pressure, high cholesterol, and atherosclerosis (a buildup of plaque in the coronary arteries).
Heart attack: blockage of blood supply to an area of the heart (50% die before reaching the hospital, 15% during treatment)
Other conditions include arrhythmias and angina pectoris
CANCER – MIDDLE ADULTHOOD
The death rate multiplies tenfold from early to middle adulthood.
Lung cancer has dropped in men (fewer smoke) and increased in women.
Cancer occurs when a cell‘s genetic program is disrupted, leading to uncontrolled growth.
Damage to the p53 gene is involved in 60% of cancers. This gene stops defective DNA from multiplying.
Having the BRCA1 or BRCA2 tumor-suppressing gene is protection against breast cancer.
CANCER
40% of people with cancer are cured.
Breast cancer is most prevalent for women, prostate cancer for men.
Lung cancer is next, followed by colon/rectal cancer.
ADULT-ONSET DIABETES
Causes abnormally high levels of blood glucose
Incidence doubles from middle to late adulthood
Effects 10% of the elderly
Inactivity and abdominal fat deposits greatly increase risks
Treated with controlled diet, exercise, and weight loss
ARTHRITIS
Osteoarthritis: most common and involves deteriorating cartilage on the ends of bones of frequently used joints
Rheumatoid arthritis: an autoimmune response leading to inflammation of connective tissue, especially the membranes that line the joints
Effects 45% of American men and 52% of women over 65. Rises to 70% in women at age 85.
NUTRITION – OBESITY IN ADULTHOOD
Adult obesity correlated with increased risk of hypertension, diabetes, & cardiovascular disease
May be a genetic propensity for obesity. It tends to run in families. (May also be learned eating patterns.)
HEALTH & DISEASE IN OLDER ADULTHOODGenerally a continuation and intensification of problems that
began in middle adulthood.
PHYSICAL DISABILITIES
Cardiovascular illness and cancer increase dramatically and remain the leading causes of death
Respiratory diseases also rise sharply Emphysema, mostly from smoking Pneumonia, 50 types
Stroke is the 4th most common killer Hemmorage or blockage of blood flow in the brain
CHRONIC CONDITIONS OF OLDER ADULTHOODArthritis
Hypertension
Hearing impairment
Heart disease
Diabetes
Asthma
Osteoporosis
OSTEOPOROSIS
Major age-related bone loss
12 to 20 % of patients die within a year of a major break such as a hip
Patients are advised to: Take calcium and vitamin D Engage in weight-bearing exercise Take HRT/ERT Take bone-strengthening medications
UNINTENTIONAL INJURY
At age 65 and older, the death rate from unintentional injuries is at an all-time high
Due to MV accidents and falls
Older adults have higher rates of traffic violations, accidents, and fatalities per mile driven than any other age group
30% of people over 65 and 40% of those over 80 have experienced a fall in the last year
Declines in vision, hearing and mobility make it harder to avoid hazards and keep one‘s balance