Presentation on theme: "Physical Development and Biological Aging"— Presentation transcript:
1 Physical Development and Biological Aging Body Growth and ChangeThe BrainSleepLongevity
2 Patterns of Growth Cephalocaudal pattern: Proximodistal pattern: Body Growth and ChangePatterns of GrowthCephalocaudal pattern:Growth occurs first at the top—the head—and gradually proceeds from top to bottom.Proximodistal pattern:Growth starts at the center of the body and moves toward the extremities
3 Height and Weight in Infancy and Childhood Body Growth and ChangeHeight and Weight in Infancy and ChildhoodInfancyAverage 20 inches, 7 ½ lbs at birthTriple weight by 1 year½ adult height, 20% adult weight by age 2EarlyChildhoodGrowth slows, patterns vary individuallyGirls slightly smaller and lighterGirls gain fat, boys gain muscleMiddle and Late ChildhoodSlower, consistent growthMuscle mass and strength increaseBoys stronger, body proportions change
4 Changes in Proportions of the Human Body During Growth Body Growth and ChangeChanges in Proportions of the Human Body During Growth
5 Body Growth and ChangePubertyPeriod of rapid physical maturation involving hormonal and bodily changes that take place in early adolescence.Two phases:Adrenarche-changes in adrenal glandsGonardarcheMenarcheSpermarche
6 Hormone Levels by Sex and Pubertal Stage for Testosterone and Estadiol Body Growth and ChangeHormone Levels by Sex and Pubertal Stage for Testosterone and Estadiol
8 Normal Range and Average Development of Sexual Characteristics in Males and Females
9 Secular Trends in Puberty Body Growth and ChangeSecular Trends in PubertyOnset of puberty beginning earlier:Norway — menarche at 17 in 1840s, now 13U.S. — menarche at 15 in 1840s, now 12½White girls at average age of 10African American girls at average age 8 to 9
10 Body Image in Puberty Adolescents become preoccupied by bodies: Body Growth and ChangeBody Image in PubertyAdolescents become preoccupied by bodies:Overall, girls less satisfied, boys more satisfiedThroughout puberty:Girls’ dissatisfaction increases-body fat increasesBoys’ satisfaction increases-muscle mass increases
11 Body Image in Puberty Early and Late Maturation: Body Growth and ChangeBody Image in PubertyEarly and Late Maturation:Early boys more positive, better peer relations.Late boys less positive but have more positive identity by 30s than early boys.
12 Body Image in Puberty Early and Late Maturation: Body Growth and ChangeBody Image in PubertyEarly and Late Maturation:Early girls more at risk for problemsSmoking and drinking.Depression and eating disorders.Lower education and occupationalattainment.Early dating and sexual experiences.Mental disorders and behavior problems.
13 Middle Adulthood Physical: Lose height, gain weight. Body Growth and ChangeMiddle AdulthoodPhysical:Lose height, gain weight.More skin wrinkling, sagging in 40s and 50s.Youth-oriented culture motivates life style changes.Strength, bone density, flexibility decrease:1 to 2 percent loss each year after age 50.Sarcopenia: age-related loss of muscle mass.
14 Middle Adulthood Cardiovascular system and lungs: Body Growth and ChangeMiddle AdulthoodCardiovascular system and lungs:HDL and LDL cholesterol, clogged arteries.Hypertension: blood pressure increases.Decreased lung capacity after age 55.Sexuality changes:Climacteric: Fertility declines.Menopause: Menstrual periods cease.
15 Lung Capacity, Smoking and Age Body Growth and ChangeLung Capacity, Smoking and Age
16 Late Adulthood Variability in physical declines: Body Growth and ChangeLate AdulthoodVariability in physical declines:Socioeconomic status is a big factor.Physical appearance:Wrinkles, age spots, height and weight lossWeightlifting can slow process.Circulatory system:Increased blood pressure; linked to chronicconditions and longevity.
17 The Brain In Infancy Changing neurons: Rapid growth of myelin sheath, dendrite and synapse connections.Blooming and pruning of connections in brain.Peak synaptic overproduction influenced by heredity and environment.
19 The Brain In Infancy At birth, greater activity in left hemisphere specializes as infants listen to speech.Motor control begins about 2 months.Brain areas do not mature uniformly.Extensive brain development in utero:Born with about 100 billion neurons.Enriched early experiences can enhancebrain growth and functioning.
20 The BrainThe Brain In InfancyShaken Baby Syndrome
21 Synaptic Density in Human Brain from Infancy to Adulthood
22 The Brain in Childhood During early childhood, the brain and head grow more rapidly than any other part of thebody.Greatest anatomical brain increases fromages 3 to 15 years.
23 Growth Curves for Head and Brain and for Height and Weight The BrainGrowth Curves for Head and Brain and for Height and Weight
24 The Brain in Adolescence Growth still occurs in adolescence:Corpus Callosum thickens.Prefrontal cortex grows: reasoning, self-control, and decision making.Amygdala matures early: emotions and anger.Adolescent emotions:Slow development of prefrontal cortex.Poor self-control; seek rewards and pleasure.Seek novelty; increased risk-taking.Lack of practical experiences; immature judgment.
25 Adulthood and Aging The Shrinking-Slowing Brain: The BrainAdulthood and AgingThe Shrinking-Slowing Brain:Brain loss: 5-10% of weight in ages 20 to 90Dendrites decrease.Death of brain cellsShrinkage of prefrontal cortex.General slowing of function in brain and spinal cord begins in middle adulthood and accelerates in late adulthood.Reductions in neurotransmitters.
26 The Adapting Brain Grows new brain cells throughout life The BrainThe Adapting BrainGrows new brain cells throughout lifedepending on environment.Dendrite growth continues in adults.Brain rewires to compensate for losses.Less lateralization with age.Findings from Nun Study:
27 Sleep in Infancy Newborns average 16-17 hours a day. Varied sleeping patterns-Longest sleep period: 11 pm to 7 am.May change from longer to shorter sleep periods.Most close to adult patterns by 4 months.More REM sleep than any other time of life.Shared sleeping with parents is controversial.
29 SleepSIDSInfant stops breathing, usually during night, and suddenly dies without apparent cause.Having siblings who died of SIDS.African American and Eskimo infants.Lower SES groups.Passive exposure to cigarette smoke.Infants ages 4 to 6 wksSleeping on stomachs, use of soft beddingLow birth weight; diagnosed with sleep apneaSleeping with pacifier
30 Sleep in Early Childhood Most young children sleep through the night and have one daytime nap.Nightmares: Frightening dreams are more common.Night Terrors: Sudden arousal from sleep.
31 Sleep in Adolescence Many adolescents are not getting enough sleep: Average 9½ hours when availableLike to stay up late, sleep late in morningsBiological clocks have hormonal shiftMelatonin production — about an hour later each day delays sleepiness at night.
32 Sleep in Adolescence Sleep deprivation and school performance: Grogginess and inattentivenessPoor test performanceDiscipline problemsReports of illness and depressionLow self-esteemIneffective stress management, exercise, diet
33 Adulthood and Aging Many adults don’t get enough sleep. Middle age may bring sleep problems.Wakeful periods at night, less deep sleep.Many older adults go to bed earlier at night and wake up earlier in the morning.Afternoon naps .Insomnia increases in late adulthood.
34 Life Expectancy and Life Span LongevityLife Expectancy and Life SpanLife span:Upper boundary of life, maximum number of years an individual can live.120 years of age.Life expectancy:Number of years that an average person born in a particular year will probably live.
35 Life Expectancy Females average 80 years, 74 years for males. LongevityLife ExpectancyFemales average 80 years, 74 years for males.Gender differences influenced by biological factors – extra X for females.Life expectancy varies across countries.U.S. men more likely to die from leading causes of death.Associated with lifestyle and workplace stress.
36 Centenarians Numbers increasing: Genes, heredity, and family history LongevityCentenariansNumbers increasing:Genes, heredity, and family historyWomen who have never marriedAbility to cope successfully with stressEducation, health, and lifestyleIndividual personalityHighest ratio in Okinawa.
37 Biological Theories of Aging LongevityBiological Theories of AgingCellular Clock TheoryMaximum times that human cells can divide is about 75 to 80People age because their cells’ metabolism produces unstable oxygen molecules (free radicals)Free-Radical TheoryMitochondrial TheoryAging caused by decay of mitochondria; oxidative damageAging in body’s hormonal system can lower resistance to stress and increase likelihood of diseaseHormonal Stress Theory