CHAPTER SEVENTEEN PHYSICAL AND COGNITIVE DEVELOPMENT IN LATE ADULTHOOD

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  • CHAPTER SEVENTEENPHYSICAL AND COGNITIVE DEVELOPMENT IN LATE ADULTHOOD

    Copyright 2009 Pearson Education Canada

  • I. VARIABILITY IN LATE ADULTHOODThe scientific study of aging is known as gerontologyLate adulthood is now thought of as a period of tremendous individual variability rather than one of universal decline

    Copyright 2009 Pearson Education Canada

  • A. Characteristics of the Elderly PopulationLife expectancy:Increases as adults get olderA 65 year old man is likely to live to be 82An 80 year man old is likely to live to be 90A 65 year old woman is likely to live to be 87A woman in her mid 80s can expect to live to over 92There are more elderly women than men, but the gender gap has been narrowing in Canada since 1981(continued)

    Copyright 2009 Pearson Education Canada

  • Characteristics of the Elderly Population (continued)Subgroups:Young-old (60 to 75)Old-old (75 to 85)Oldest-old (85 and up) (fastest growing group)From 1981 to 2000, the over-65 population in Canada increased by about two-thirds, and the over-85 population almost tripledFrail elderly: older adults whose physical and/or mental impairments are so extensive that they cannot care for themselvesIn the future, there may not be enough young and middle aged adults to care for the elderly(continued)

    Copyright 2009 Pearson Education Canada

  • Characteristics of the Elderly Population (continued)HealthThe majority of older Canadian adults across all three age subgroups regard their health as good or excellentPoor health is proportionately higher than in younger groups Fair or poor health is self-reported by 32 % of those over 75 years of ageHealth is the single largest factor determining the trajectory of an adult's physical or mental status over the years beyond 65An optimistic view helps seniors recover better from illnesses such as strokeChronic illness at age 65 is predictive of more rapid declines in later life(continued)

    Copyright 2009 Pearson Education Canada

  • Self-Ratings of Elders Health

    Copyright 2009 Pearson Education Canada

  • Characteristics of the Elderly Population (continued)Cognitive FunctioningAlzheimers disease, an irreversible degenerative condition, is the most common cause of dementiaOther sources of mental confusion include intercurrent illnesses, infections, metabolic disturbances and drug intoxicationsLittle of the cognitive impairment is reversibleEven among those over 85, the majority do not have cognitive impairments

    (continued)

    Copyright 2009 Pearson Education Canada

  • Percentage of Adults with Cognitive Impairments (USA)

    Copyright 2009 Pearson Education Canada

  • Characteristics of the Elderly Population (continued)Cognitive Functioning (continued)Variations in hormones are related to variations in cognitive performance in men and womenThe relationship between hormones and cognition is not understoodGiving women hormone replacement therapy does not improve their cognitive functioningHormone replacement therapy may increase the chance of serious cognitive dysfunction(continued)

    Copyright 2009 Pearson Education Canada

  • Characteristics of the Elderly Population (continued)Mental ExerciseHumans who challenge themselves with complex mental activities can delay or even reverse the normal decline in brain mass that is part of primary agingSome enhancement or better maintenance of intellectual skills results from an "engaged" and intellectually active lifestyle

    (continued)

    Copyright 2009 Pearson Education Canada

  • Characteristics of the Elderly Population (continued)Limitations on Activities:Functional status: a measure of an individuals ability to perform certain roles and tasks, particularly self-help tasks and other chores of daily livingActivities of Daily Living (ADLs): self-help tasks such as bathing, dressing, and using the toiletInstrumental Activities of Daily Living (IADLs): more complex daily living tasks such as doing housework, cooking, and managing moneyThe proportion of older adults with disabilities increases with ageThe physical problems or diseases that are most likely to contribute to some functional disability in late adulthood are arthritis and hypertension

    Copyright 2009 Pearson Education Canada

  • Proportions of Canadian Seniors with Chronic Health Conditions

    Copyright 2009 Pearson Education Canada

  • B. LongevityLongevity appears to result from interactions among heredity, environment, and behavioural choicesThe maximum life spanThose over 100 represent the fastest growing population groupMaximum lifespan seems to be ~ 110 or 120 yearsHayflick limit: the theoretical proposal that each species is subject to a genetically programmed time limit after which cells no longer have any capacity to replicate themselves accurately(continued)

    Copyright 2009 Pearson Education Canada

  • Longevity (continued)The maximum life span (continued)Telomere: string of repetitive DNA at the tip of each chromosome in the body that appears to serve as a kind of timekeeping mechanismThe number of telomeres decreases each time a cell dividesIf there is a crucial number of telomeres, disease or death may come quickly once that number is passed

    (continued)

    Copyright 2009 Pearson Education Canada

  • Longevity (continued)Individual HeredityThere is a large range of individual differences in how long people liveSome general tendency toward longevity is clearly inheritedIdentical twins are more similar in length of life than are fraternal twinsAdults whose parents and grandparents were long-lived are also more likely to live longer

    (continued)

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  • Longevity (continued)Health HabitsThe same health habits are important now as in earlier yearsSmoking, low levels of physical activity, significant under- or over-weight predict increased death riskSmoking limits longevity: 65-year-old male smoker can expect to live six years less than a non-smoker and a female smoker will live 8.5 years lessSmokers are also more likely to suffer disease related disabilitiesby age 65 more than half of all smokers will have a disability (compared to one-third of non-smokers)

    (continued)

    Copyright 2009 Pearson Education Canada

  • Longevity (continued)Health Habits (continued):Physical exercise is clearly linked to greater longevity and lower rates of diseases such as heart disease, cancer, osteoporosis, diabetes, gastrointestinal problems, and arthritisDelays admission to nursing homesImproves strength and motor skills after only 12 weeks of exercisehelps maintain higher levels of cognitive performance among the elderly

    (continued)

    Copyright 2009 Pearson Education Canada

  • Longevity (continued)Health Habits (continued):Physical exercise is even more important in later years than in youthAs much as half of the decline in physical (and perhaps cognitive) function can be prevented through improved lifestyle, especially exerciseStill, only 27% of older adults are active enough to see these benefitsCanadas Physical Activity Guide recommends 30 to 60 minutes of exercise daily, that can be accumulated in segments of 10 minutes or longerObesity in this age group is rising (19% for men, 27% for women)

    Copyright 2009 Pearson Education Canada

  • II. PHYSICAL CHANGESDespite variability in health and functioning among the elderly, there are several changes in physical functioning that characterize the late adult years for almost everyone

    Copyright 2009 Pearson Education Canada

  • A. The Brain & Nervous SystemFour main changes occur in the brain: a reduction of brain weighta loss of grey mattera loss of density in the dendritesslower synaptic speedLoss of dendrites is not only primary aging, but is linked to education: less cerebral cortex atrophy occurs in those with more educationLoss of dendrites results in slowing synaptic speed, and therefore slowing in reaction timeSynaptic plasticity can not make up for the loss of dendrites

    (continued)

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  • The Brain & Nervous System (continued)There is an insignificant loss of neurons themselves, and there are so many redundancies in the nervous system that there is little impactWhen significant interconnectivity is lost, which occurs as dendrites shrink in number, "computational power" declines and symptoms of old age appearAlthough new neurons continue to be produced in adulthood, the effects of this regeneration are not known

    Copyright 2009 Pearson Education Canada

  • B. The Senses & Other Body SystemsVisionPresbyopia (farsightedness) increasesAn enlarged "blind spot" on the retina reduces field of vision The pupil does not widen or narrow as much or as quickly resulting in more difficulty seeing at night and responding to rapid changes in brightnessDiseases of the eye (in a minority of people) such as cataracts or glaucoma, further diminish visual acuity and adaptabilityYounger people cope better with changes in visionVision loss has a greater impact on an elderly persons sense of well-being(continued)

    Copyright 2009 Pearson Education Canada

  • The Senses & Other Body Systems (continued)Hearing:Presbycusis isnt usually functionally limiting until late adulthoodMen lose more hearing than women do, likely due to more occupational exposureThe ability to hear high-frequency sounds (part of human speech) is diminishedWord discrimination becomes problematic, especially under noisy conditionsTinnitus, a persistent ringing in the ears, increasesSevere hearing loss is associated with social and psychological problemsPhysical changes in the ear contribute to problems(contin