Transcript Slide 1
Chapter 5 The Physical Self Chapter 5: The Physical Self Genetic and environmental forces e.g. height Average: Can be affected by malnutrition Catch-up growth possible After illness or periods of malnutrition More female 5’4” male 5’9” 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 Breathing, eye-blink,sucking/rooting Primitive reflexes: clearly adaptive 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 Late/males: Disadvantageous More positive reactions from others 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 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 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