Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Chapter 5
The Physical Self
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Chapter 5: The Physical Self
• Genetic and environmental forces e.g. height
– Average: female 5’4” male 5’9”
– Can be affected by malnutrition
– Catch-up growth possible
• After illness or periods of malnutrition
– More short people in cold climates
• Smaller body surface for heat loss
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Endocrine System
• Glands that secrete hormones
• Pituitary gland: the master gland
•
•
– Controls all other glands
– Is controlled by the hypothalamus
– Produces growth hormone
Testes secrete androgens like testosterone
Ovaries secrete estrogen and progesterone
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Figure 5-2
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Plasticity
• Responsiveness to experiences
– Can be negative
• Vulnerable to damage
• Environmental deprivation
– Can be positive
• Aids in recovery from from injury
• Can compensate for each other
• Can benefit from stimulation
• Allows for adaptability
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Brain Development 2
• Critical period: late prenatal & early infancy
• Lateralization (at birth)
– Left hemisphere
• Analytic reasoning, language
– Right hemisphere
• Understanding spatial information
• Visual-motor information
– Corpus callosum connects the two
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Brain Development 3
• Never truly complete
– Changes occur across lifespan
• Growth spurts in infancy, childhood and
adolescence
• Full adult weight by about age 16
• Processing speed increases in adolescence
• Myelination continues into adulthood
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Brain Development 4
The Aging Brain
– Gradual and mild degeneration
Elderly adults
– 5-30% fewer neurons than younger adult
– Greater loss in sensory-motor areas
– Plasticity still possible
Main result of age is slower processing
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Principles of Growth
• Procession of growth is orderly
– Cephalocaudal: from head, downward
– Proximodistal: from the center, outwards
– Orthogenic: from global, undifferentiated to
specialized
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Infant
• Typically 7 to 71/2 lbs., 20 inches long
• Period of rapid growth
• Neonatal reflexes (see Table 5.3 in text)
– Survival reflexes: clearly adaptive
• Breathing, eye-blink,sucking/rooting
– Primitive reflexes: less adaptive
• Typically disappear by 4 months
–Babinski: toes fan
–Grasping
• Used diagnostically
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Infant 2
Behavioral States
– Short sleep-wake cycles at first
– Establish more regularity at 3-6 months
– REM sleep
• 50% of the time for newborns
• 25-30% by 6 months
– May be useful for reducing stimulation
– Individuality in infant patterns
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Infant 3
• Strengths and weaknesses
– Sensory system in tact
– Ability to learn from experience and from
consequences
– Limited in capacity to move voluntarily
– Intentionality also limited
– Cannot interpret complex stimuli
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Infant Physical Behavior
• Developmental norms (see Table 5.5 )
•
•
•
•
– Average age of mastery
Gross before fine motor skills
Crawling at 7–10 months
Walking at about 1 year
Study of “walkers” (Siegel & Burton, 1999)
– Infants not using walkers sat up, crawled,
and walked earlier
– Need sensory feedback I.e.,to see feet
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Physical Behavior 2
Manipulating Objects
– Grasping reflex disappears: 2-4 mo
– Pincer grasp by 6 months
Motor Skills
– Rhythmic Stereotypies
• Rocking, bouncing, mouthing objects,
banging arms and legs
• Precede a skill then disappear
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Dynamic Systems Approach
A self-organizing process
– Trying new movements
– Use sensory feedback
– Motor milestones are learned
– Also require maturation
– A nature/nurture position
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Child
Age 2 until puberty
– 2-3 inches in height, 5-6 lbs weight
– Bones grow and harden
– Run faster, jump higher, and throw a ball
farther
– Skills very responsive to practice
– Hand-eye coordination, fine motor, and
reaction time all improve
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Adolescence
Growth spurt triggered by hormones
– Peak in height: age 12/girls, 14/boys
– Menarche: average age 12 1/2
• Earlier in countries with good nutrition, longer
life, and higher literacy rates
– Maturation different by ethnicity
• AA and MA girls earlier than White
– Semenarche: average age 13
• emission of seminal fluid
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Rates of Development
Genes set the process in motion
Hormones responsible for changes
Environment also
– Secular trend: better nutrition
• Earlier maturation,larger body size
– Poorly nourished/mature later
– Heavy & tall/mature earlier
– Regular strenuous exercise/later
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Figure 5.6
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Psychological Implications
Girls become concerned w/appearance
– Individual reactions vary widely
– Negative views about menstruation
– May contribute to poor body images
Boys likely to welcome the changes
Family relations remain important
– Distance & conflict with parents
• Usually about only minor issues
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Early vs. Late Development
Early/males: advantage
– More positive reactions from others
Late/males: disadvantage
– More behavior & adjustment problems
Early/females: disadvantage
– Subject of ridicule,lower self esteem
– Older peer group = problems
Late/ females: academic advantages
Differences tend to fade with time
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Physical Behavior
Dramatic physical growth overall
Boys continue to improve
Girls tend to level off or decline
Not totally explained by biology
– Gender role socialization important
– Gender performance gap has narrowed
– E.g., track, swimming, cycling records
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Adult
Minor changes in the 20s & 30s
Noticeable by the 40s
– Wrinkles, gray hair, weight gain
In the 60s: Weight, muscle, bone loss
– Osteoporosis in older women
• Fair, light frame, smokers
• Calcium, exercise, HRT
– Osteoarthritis: joint deterioration
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Functioning and Health
• Most systems show decline with age
– Heart & lung capacity
– Temperature control
– Immune system and strength
– Reserve capacity
• *On average, older people are less fit than
younger BUT not all
• Physically active remain fit
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
The Reproductive System
Beginning in adolescence
– Sex hormones influence behavior
• Males/testosterone
–Levels fluctuate daily
• Females/ estrogen & progesterone
– monthly cycle
–PMS? Expectations vs. hormones
»Calcium & Vitamin D helpful
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Menopause and Andropause
Menopause: estrogen production declines
– age range 45-54
– Symptoms: hot flashes, vaginal dryness
– Little anxiety, irritability, depression, or
other stereotypes
– Exercise & adequate sleep helpful
Andropause: decreasing testosterone
– Symptoms: Libido, fatigue, erection, and
memory problems
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Slowing Down
Balance difficulty affects the ability to walk,
stand, sit, and turn
Older people with strong muscles and good
cardiovascular capacity can walk briskly
Central change is slowing in the CNS
– Increased RT
– Novel/complex tasks more difficult
*physically fit older people have quicker RT
Life-Span Human Development, Fifth Edition, Carol K. Sigelman and Elizabeth A. Rider
Chapter 5
Disease, Disuse, and Abuse
Birren (1963) study of men aged 65-91
– Healthy older same as younger
– Conclusion: Aging itself has little effect on
physical and psychological functioning
Disuse: “Use it or loose it!”
– Includes mental exercise
Abuse contributes to decline
– Alcohol, high-fat diet, smoking