Chapter 5 The Physical Self

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

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

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

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

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

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

Principles of Growth Procession of growth is orderly  Cephalocaudal: from head, downward  Proximodistal: from the center, outwards  Orthogenic: from global, undifferentiated to specialized

A Life-Span Developmental Model of Health Health: A life-long process Determined by both genetic and environmental factors Is multi-dimensional: well-being, illness Changes involve both gains and losses Sociohistorical context: SES

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

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

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

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

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

Dynamic Systems Approach A self-organizing process  Trying new movements  Use sensory feedback  Motor milestones are learned  Also require maturation  A nature/nurture position

Adolescence Growth spurt triggered by hormones  Peak in height: Age 12/girls, 14/boys Menarche: Average age 12½ Earlier in countries with good nutrition Maturation different by ethnicity AA and MA girls earlier than White Semenarche: Average age 13 Emission of seminal fluid

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

Psychological Implications Girls become concerned w/appearance  Individual reactions vary widely  Negative views about menstruation Boys likely to welcome the changes Family relations remain important  Distance and conflict with parents Usually about only minor issues

Early versus Late Development Early males: Advantageous  More positive reactions from others Late/males: Disadvantageous  More behavior and adjustment problems Early/females: Disadvantageous  Subject of ridicule, lower self esteem  Older peer group = problems Late/ females: Academic advantages Differences tend to fade with time

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

Health and Wellness in Adolescence Obesity a continuing problem  Higher risk: Diabetes, heart, BP problems  Poor eating habits, sedentary lifestyle Leading causes of death  Motor vehicles and violence Alcohol and drug use, cigarette smoking  Also result in risky choices

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

Functioning and Health Most systems show decline with age  Heart and 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

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 Major change is slowing of the CNS  Increased RT  Novel/complex tasks more difficult Physically-fit older people have quicker RT

Disease, Disuse, or Abuse? Birren (1963) study of men aged  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

Health and Wellness in Old Age Acute illnesses less common Chronic disease more common Most 70-yr-olds: At least 1 chronic impairment Tremendous variability Exercise, nutrition: Lifelong benefits  Improves cardio, respiratory functioning  Slows bone loss, strengthens muscles  Less depression, delays disability

Diseases Common in Old Age Osteoporosis: Smokers, light frame, at risk  Increase calcium  Weight-bearing exercise Osteoarthritis: deterioration of cartilage Successful aging  Both physical and mental functioning  Positive attitude