Developing and Aging
ACROSS THE LIFESPAN


Biology 266     —     Life Span part 4a

SENIOR YEARS--  OLDER ADULTS:
  • Late adulthood: Demographics
    • More elderly adults (living longer) and fewer young in all developed countries.
    • In Japan & much of Europe: population already older than in U.S.
    • Families having fewer children-- approaching "Zero Population Growth"
      (This is world-wide, but in U.S. immigration slows this trend a bit)
    • Social consequences: More resources needed for elder care (hospitals, nursing care);
          fewer resources needed for schools, etc.
    Aging Populations
  • Longevity:
    • Avg. longevity increasing everywhere (more retired people, fewer wage earners)
    • Maximum longevity increasing-- more nursing and elder care facilities needed
    • Also: Healthier elderly-- more cruise ships, golf, etc.
    • If you have long-lived parents and grandparents, your chances of living longer are increased.
    • Women generally live longer than men (~5 yrs on average); ethnic groups vary
    • Internationally: Abkhazia*, Switzerland: older adults stay active, so they live longer!
          *Autonomous, mountainous region in western Republic of Georgia, east of Black Sea
          Staying active >60 is important; mountainous terrain helps (Tibet, parts of Peru, too)
        Japan, Spain, Italy, etc.: older adults more respected, encouraged to stay
              socially engaged and healthy, so they live longer!
    • Age 60-80 sometimes called "Third age"-- healthier physically, help families, emotional well-being valued, also cognitive wisdom
    • Age 80+ called "Fourth age"-- more frail, more dependent (burden on many families), more cancer, more Alzheimer's disease
      Notable people professionally active past age 80
      Name Dates Active until-- Lived until..
      Frank Sinatra, singer 1915-1998 Performed until age 80 83
      Maurice Chevalier actor, singer 1888-1972 Performed until age 82 84
      Irving Berlin, song writer 1888-1989 Composed untoil age 83 101
      Georgia O'Keefe, painter 1887-1986 Painted until age 85 99
      Julie Andrews, actress, singer 1935-now Still performing85+
      Bea Arthur, actress1922-2009 Performed until age 86 87
      Jane Goodall, primatologist 1934-now Still lecturing86+
      Arturo Toscanini, conductor 1867-1957 Conducted until age 87 90
      Arthur Rubinstein, pianist 1887-1982 Performed until age 89 95
      Pablo Casals, cellist 1876-1973 Composed and
      performed until age 94
      97
      Betty White, actress 1922-now Still acting 98+
      Sewall Wright, geneticist 1889-1988 Published until age 99 99
      Interviewer: "How do you feel about growing old?
      Maurice Chevalier: "It's very nice, when you consider the alternative."
  • Biological theories of aging:
    • Telomeres on ends of chromosomes shorten with each cell division; this eventually limits cell repair (unless "telomerase" is present, as in embryonic cells or in cancer)
    • "Free radicals" (molecules with unpaired electrons) cause genetic damage. Diet rich in antioxidants lowers cancer risks & prolongs life.
  • Physiological changes:
    • Brain and nervous system:
      • Neurons with less sprouting
      • Buildup of beta-Amyloid protein leads to Alzheimer's disease; also neurofibrillary tangles inside nerve cells causes them to die
      • Cell damage leads to loss of some neurotransmitters (e.g., Parkinsonism)
      • Neuroimaging shows: Brain tissue shrinks, brain cavities (vesicles) may enlarge.
    • Cardiovascular system:
      • Atherosclerosis (fat deposits, which may calcify): higher risk of strokes, heart disease
      • Arteriosclerosis: lining of arteries harden and become less elastic
      • Transient Ischemic Attacks ("mini-strokes"): interrupted blood flow; early sign of impending larger stroke
      • Vascular dementia: many small strokes in brain
      • Heart attacks (myocardial infarction =death of heart muscle tissue)
    • Respiratory system: COPD (Emphysema & Chronic bronchitis)-- much more in former smokers or those exposed to air pollution
    • Vision loss:
      • Presbyopia (near-sightedness): need reading glasses, don't see as well at night
      • Cataracts-- opaque spots in lens tissue
      • Glaucoma-- lens gets stiffer, less ability to focus
      • Macular degeneration-- loss of retinal cells, often leads to blindness
      • Diabetic retinopathy-- death of cells from blood vessel damage in retina
    • Hearing loss: Sensitivity to high-pitched tones declines the most (presbycusis)
  • Chronic diseases:
    • Diabetes (especially type 2)
    • More cancers
    • Frequent declines in sleep
    • Nutritional deficiencies from eating less
      Advice: Eat less, but keep up vitamins, fiber (fruits, vegetables, whole grains), & fish
      Mediterranean and DASH diets emphasize low-fat proteins (like fish, yogurt, cottage cheese), healthy fats*, lots of fruits, grains, and vegetables
            *includes omega-3 fatty acids (fish, nuts) and monounsaturated
            fatty acids (olive oil), but avoid saturated fats (red meats)
  • Attitudes of others is important; important to remain socially engaged
          (if no longer employed, then volunteer, get active in church or community group, etc.)
  • Cognitive decline (proceeds faster if poor cardiovascular health):
    • Slower reaction time (driving can become a problem)
    • Multitasking skill declines (more easily distracted, which causes forgetting)
    • Memory loss:
      • Working (short-term) memory-- remembering a phone number long enough to dial
        Test with random words; "digit span"-- Can you repeat a list of 5 digits? 8 digits?
      • Implicit memory = unconscious (often kinesthetic): tying a bow, using a can-opener
      • Explicit memory = deliberate, conscious (often verbal)
      • Episodic memory = memory or past events
      • Semantic memory = meanings of words
      • Autobiographical memory = memory of events from one's distant past
      • Some memory loss in normal, but abnormal if it impairs daily functioning
  • Memory aids-- "E I E I O":
        E=Explicit memory     I=Implicit memory
        E=External aid     I=Internal aid       O="Oh, now I remember!"
    • Explicit, external-- grocery list, appointment book, pill organizer (with compartments)
    • Implicit, external-- color-coded maps, doors, signs
    • Explicit, internal-- mental imagery, rote rehearsal, mnemonics, tunes
    • Implicit, internal-- learned associations (conditioning): I live in the yellow house; turn left at the brown door; go just past the fire extinguisher
  • Creativity (of artists, composers) peaks in 30s and 40s; it declines with age (but not always)
  • Wisdom-- not always age-related but more more revered
    Older people remember more examples;   Tell more stories to young;   Have more patience
  • Mental health:
    • Loneliness-- living with family is best; even pets; keeping in touch often
    • Depression (dysphoria) is less common in elderly
      • Treatment in elderly (when needed):
        • Behavior therapy (encourage more social contacts), or
        • Cognitive therapy (learn to recognize negative thoughts, substitute positive ones)
    • Anxiety disorders MORE common in elderly:
      Treatments include psychotherapy; benzodiazepine drugs like Valium, Librium, Paxil (but beware of overdoses)
    • Dementia incl. Alzheimer's: Hard to treat; some drugs can slow progress but not reverse
      • Brain changes: APO-ϵ4 allele; β-amyloid (especially small 'oligomers', then clumps or 'plaques'); then phosphorylation of tau protein, causing neurofibrillary tangles
      • Symptoms include forgetting names of loved ones, losing sense of place (lost in places once familiar), etc.
      • Progressive disease: can slow but never reverse
      • Diagnosis p. 494-- many other causes to rule out
    • Incontinence (loss of bladder control): adult diapers used
    • Parkinson disease: loss of cells in basal ganglia of brain; loss of dopamine that they secrete
        --starts with tremors; shuffling gait; hard to initiate movement or lift feet
    • Chronic Traumatic Encephalopathy (CTE): from repeated brain injuries (often in football, boxing)



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Syllabus
rev. Apr. 2021