Module 4: Theories of aging

Genetic Theories

• States that the life span of a human is programmed within the genes, thus for short or long life.

• The genetic theory of aging states that lifespan is largely determined by the genes we inherit. According to the theory, our longevity is primarily determined at the moment of conception and is largely reliant on our parents and their genes.

Random Error Theory

• Also known as The Error Catastrophe (Accumulation) Theory

• Aging results from errors and changes in the genetic information involved in cellular protein formation.

• We produce cells throughout our body using our same correct DNA (or proteins). If over time an error or mistake occurs in our DNA map, it begins to produce cells that are not correct.

• Hutchinson–Gilford progeria syndrome (progeria), premature aging - characterized by age-associated symptoms at an extremely young age.

Gene Regulation Theory

• That one or more harmful genes in the organism become active in later life, causing failure of the organism to survive

• That there are two types of genes:

  1. Juvenescent genes

  2. Senescent genes

Juvenescent genes

• those that mediate youthful vigor & mature adult well-being; function in early life

Senescent genes

• those that promote functional decline & structural deterioration; activated in middle age

Somatic Mutation Theory

• Mutation – a change in the copy of your DNA contained by the new cells.

• All of the cells in our body are considered somatic cells, except our reproductive cells (sperm and eggs)

• Mutations occurring in cells other than the reproductive cells are referred to as somatic mutations

• The body can correct or destroy most of the mutations, but not all of them. Eventually the mutated cells accumulate copy themselves and accumulate with increasing age, causing cells to deteriorate and malfunction. As people live beyond 90 and 100 years, more of them die from multiple organ failure due to aging. The lungs, heart, liver, kidneys, muscles, and every other organ suffers from the effects of long-term somatic mutation.

DNA Damage Theory

• DNA is involved in the mapping or identification of the human genome

• the lifespan is programmed in DNA molecule before birth.

• aging is a result of unrepaired DNA damage accumulation

• Irreparable DNA damage is caused by: Environmental pollutants, Low dose ionizing radiation, Food additives, particularly nitrites & nitrates

• DNA damage can have two main results: -Mutation - alter the function of the cell & cell death or apoptosis (prevent the cell from doing its function)

Non-Genetic Cellular Theory

• - Suggests that changes occur in the cellular proteins after their formation

• Attribute aging to progressive cell damage caused by the internal and external environment, rather than to an innate genetic program

• With the passage of time, changes occur in the cells that impair their effectiveness.

Free Radical Theory

• Oxidative Stress theory

•  Free radicals - byproducts of metabolism

• charged molecules with unpaired electrons

• chemicals that contained oxygen in high activated state react and interact with other molecules during normal metabolism and as they interact with our tissues, they “steal” electrons from other molecules and cause “oxidation.” When these byproducts accumulate, it prevents proteins and other essential molecules to function as they should, they damage the cell membrane which decreases its efficiency.

• The body produces antioxidants that scavenge the free radical

Antioxidants

• chemicals that prevent the formation of free radicals thus, it is called “the Free Radical Sponge”

• neutralize free radicals, which damage cells, clog arteries and contribute to chronic illness and aging

• Sources: Whole, organic foods (avoiding processed foods and artificial chemicals used for preservation, coloring and flavoring), leafy vegetables, fruits, wine, and chocolate, exercise, a clean environment avoid excessive exposures to toxic air pollution, chemicals such as solvents and industrial waste that leak into water supplies, harsh cleaning and cosmetic chemicals, heavy metals, unnecessary medications, and pesticides), Stress free lifestyle 

Cross-Linking Theory (Glycosylation Theory )

• bonds or cross- linkages develop between molecules

• As the cells age, reactions create strong bonds especially collagen tissues

• The process of occurs because exposure to certain types of sugar lead to the process known as glycation which in turn lead to the formation of Advance Glycation-End products (AGE).

• The AGEs induce cross linking of collagen which in turn increases, for example, stiffness of skeletal muscle and cartilage. (arteriosclerosis)

• can be found in: Unsaturated fats, Polyvalent metal ions (e.g. Aluminium, Zinc and magnesium) & excessive radiation exposure

Accumulation Theory / Waste Accumulation Theory

• When cells produce more waste (toxins) than they can properly eliminate, this waste when accumulated to a certain level, can interfere with normal cell function, ultimately killing the cell.

• Substances such as waste materials and lipofuscin accumulate in the cells of living organisms until they interfere with cellular functioning.

• The key to fight against lipofuscin accumulation:

• avoid oxidative damage, avoid direct exposure to sunlight (wear sunglasses, to prevent buildup of lipofuscin (druzen) that can cause macular degeneration), avoid contact with x-rays and microwaves, remain cautious while dealing with toxic substances, proper diet (menu may consist of sardines, broccoli, blueberries, Green Tea and olive oil)

Lipofuscin

• a product of oxidation of unsaturated fatty acids and described as “the ashes of our dwindling metabolic fires”

• a small granular yellow-brown pigment that can appear in nerve cells, heart, muscle, kidney, liver, ganglion cells and adrenals.

• Accumulate in the cells as small granules and increases in size as a person ages.

Deprivation Theory

• Aging is caused by vascular changes that deprive cells of essential nutrients & Oxygen

• Caloric Restriction

• An individual on this program would lose weight gradually until a point of metabolic efficiency was reached for maximum health & life span.

• Reducing calories, while continuing to provide adequate nutrients, results in extension of the lifespan.

• Absolute Deprivation- Physical abuse, starvation, poverty

• Relative Deprivation- Discrepancy between what one expects in life, and one gets

Wear-and-Tear Theory (Hans Selye)

• Suggest that years of damage to cells, tissues and organs eventually wears them out.

• Once they wear out, they can no longer function correctly, killing them and then the body.

• Cells are continually dying and being replaced in order for the body to maintain itself.

• As we age, the ability to replace the worn out and discarded cells is lessened by the experience over a lifetime

• Stress - Is a non-specific response of the body to any demands made upon it.

• These stresses and their effects vary on: Individual’s personality, Coping mechanisms, Occupation & Lifestyle

Metabolic Theory of Aging (MTA) 

• proposes that aging is driven by the accumulation of cellular damage and dysfunction due to metabolic processes. 

• Metabolic rate and longevity: The theory suggests that organisms with higher metabolic rates tend to have shorter lifespans.

• Oxidative stress and damage: Metabolic processes generate reactive oxygen species (ROS), which can damage cellular components, contributing to aging.

• Energy allocation and trade-offs: The theory proposes that energy allocation to growth, reproduction, and maintenance affects aging, with trade-offs between these processes influencing lifespan.

Physiologic Theories

Explains aging on the basis of a breakdown of an organ system or impairment in neuroendocrine or physiologic control mechanism

Biological Clock Theory

• - Aging is programmed

• This is based on the idea that from conception to death, human development is governed by a biological "clock." This clock sets the appropriate time for various changes to take place.

• Changes in vision, loss of calcium in the bones, decreasing hearing acuity and lowered vital capacity of the lungs are all examples of programmed aging.

• states that cells are pre-determined to continue through a finite number of divisions before dying off.

• This theory was divided into three subcategories:

  1. Endocrine Theory

  2. Programmed Senescence Theory

  3. Immunological Theory

Endocrine Theory

• states that biological clocks act through hormones, secreted by the endocrine glands, to control the pace of ageing.

• Production of some hormones declines with age

Programmed Senescence Theory

• Senescence is the age when an organism’s viability is reduced dramatically due to impaired physiology

Immunological Theory

• Programmed decline in the functioning of the immune system leads to increased vulnerability to infectious diseases thus causing ageing and death.

Immune Theory

• - Immune System

• Network of specialized cells, tissues and organs that provide the body with protection against invading organisms.

• Protect us against viruses and bacteria

• Immune system acts in 2 ways: - by generating antibodies that react with the proteins of foreign organisms (B lymphocytes – humoral) & produces antibody molecules in response to an antigen by forming cells that engulf           and digest foreign cells (T lymphocytes – cell mediated immunity) T lymphocytes defend the body from infectious disease, cancer, and foreign substances

• that the rate of aging is largely controlled by the immune system

• Before age 20, the thymus (which produced certain immune cells) begins to shrink. Thus, as we age, the numbers of critical cells in the immune system decrease and become less functional.

• Immunosenescence- age related decrease in the function of the immune system

Glycation Theory or Maillard reaction / non-enzymatic glycosylation

• is the nonenzymatic reaction between glucose and tissue protein, therefore glucose acts as mediator of aging

• The hypothesis of aging suggests that modification of proteins by glucose and associated browning or Maillard reactions leads to: gradual cross-linking, polymerization, development of brown-color products, &              linked to protein clumps in Alzheimer’s patients

• Glycation causes: connective tissue to lose elasticity, reduced kidney function, slowed wound healing, reduced vital capacity of the lung, contributes to cataracts

• Prevention of Glycation: Lifestyle, food cooked at high temperatures and other diets that cause high blood glucose levels be avoided

• Diet composed of fruits, fish, lean protein, whole-grain pasta, vegetables, olive oil and even a little toast of red wine

• Avoid direct exposure to sun

Continuity Theory

• States that older adults will usually maintain the same activities, behaviors, personalities, and relationships as they did in their earlier years of life.

• Old age is not seen as a separate period of life, but as a continuation of some patterns set earlier, especially coping strategies of acting, thinking, and feeling.

• is positively related to successful aging

     Elements:

1. Internal structure

2. External structure

Internal structure

• personality, ideas, and beliefs

• provides the individual a way to make future decisions based on their internal foundation of the past.

External structure

• relationships & social roles

• provides a support for maintaining a stable self- concept and lifestyle

Disengagement Theory

• States that "aging is an inevitable, mutual withdrawal or disengagement, resulting in decreased interaction between the aging person and others in the social system he belongs to".

• Withdrawal may be initiated by the aging person or by society and may be partial or total.

• Four basic concepts on this theory:
  1) The aging person and the society mutually withdraw from each other
  2) Disengagement (withdrawal) is biologically and psychologically intrinsic
  3) Disengagement is considered necessary for successful aging
  4) Disengagement is beneficial for both elderly and society

Postulate 1 : Everyone expects death, and one's abilities will likely deteriorate over time. As a result, every person will lose ties to others in his or her society

Postulate 2 : Because individual interactions between people strengthen norms, an individual who has fewer varieties of interactions has greater freedom from the norms imposed by interaction.

Postulate 3 : Because men have a centrally instrumental role, and women a socio-emotional one, disengagement differs between men and women.

Postulate 4 : The individual's life is punctuated by ego changes. his is affected by the individual, prompted by either ego changes or the organization—which is bound to organizational imperatives—or both.

Postulate 5 : When both the individual and society are ready for disengagement, complete disengagement results. When neither is ready, continuing engagement results. When the individual is ready and society is not, a disjunction between the expectations of the individual and of the members of this social systems results, but engagement usually continues. When society is ready and the individual is not, the result of the disjunction is usually disengagement.
Postulate 6 : Man's central role is work, and woman's is marriage and family. If individuals abandon their central roles, they drastically lose social life space, and so suffer crisis and demoralization unless they assume the different roles required by the disengaged state.

Postulate 7: Readiness for disengagement. Each level of society grants individuals permission to disengage

Postulate 8: Fewer interactions and disengagement from central roles lead to the relationships in the remaining roles changing. In turn, relational rewards become more diverse, and vertical solidarities are transformed to horizontal ones.

Postulate 9: Disengagement theory is independent of culture, but the form it takes is bound by culture.

Activity Theory

• Implicit Theory of Aging

• Normal Theory of Aging

• Lay Theory of Aging

• States that continuing activities from middle age promotes well-being and satisfaction in Aging

• Older adult must compensate for the loss of roles experienced in the later maturity and the need to maintain moderate active lifestyle

  What are the problems with activity theory?
        - Differences in Personality
        - Differences in physical function
        - Control over social situation
        - Socioeconomic effects
        - Cultural effects

• Assumptions in the Theory:

  • There is an abrupt beginning of old age.

  • The process of aging leaves people alone & cut-off.

  • People should be encouraged to remain active & develop own-age friends.

  • Standards & expectations of middle age should be projected to older age.

  • Aging persons should be encouraged to expand & be involved.

Symbolic Interaction Theory

• is the way we learn to interpret and give meaning to the world through our interactions with others.

• It focuses attention on the way people interact through symbols: words, gestures, rules and roles

• Major Premises of Theory:

  • Human beings act toward things on the basis of the meaning they have

  • The meaning attributed to those things arises out of social interaction with others

  • These meanings are modified through an interpretative process

Sigmund Freud Psychosexual Development

• believed that early experiences play a large role in personality development and continue to influence behavior later in life.

• Personality develops through a series of childhood stages during which the pleasure-seeking energies of the id become focused on certain erogenous areas.

• This psychosexual energy, or libido, was described as the driving force behind behavior

• If these psychosexual stages are completed successfully, the result is a healthy personality.

• If certain issues are not resolved at the appropriate stage, fixation can occur

Freud’s Stages of Psychosexual Development

• The Oral Stage (Birth to 1 Year) Erogenous Zone: Mouth

• The Anal Stage (1 to 3 years) Erogenous Zone: Bowel and Bladder Control

• The Phallic Stage (3 to 6 Years) Erogenous Zone: Genitals

• Latency Period (6 to Puberty)

• The Genital Stage (Puberty to Death) Erogenous Zone: Maturing Sexual Interests

Erik Erikson- Psychosocial Development

• Life is a series of lessons and challenges which help us to grow

• theory refers to 'psychosocial crisis' which represents internal emotional conflict or an internal struggle or challenge which a person must negotiate and deal with in order to grow and develop.

• If the balance is toward the positive, will help him to meet later crises with a better chance for unimpaired total development

• Where a person passes unsuccessfully through a psychosocial crisis stage, they develop a tendency towards one or other of the opposing forces, which becomes a behavioral tendency, or even a mental problem. In crude terms we might call this 'baggage' or a 'hang-up'

Erikson’s Psychosocial Developmental Theories

0 – 1 yr - Trust vs. Mistrust
1 - 3 yrs - Autonomy vs. Shame and Doubt

3 - 6 yrs - Initiative vs. Guilt
6 - 11 yrs - Industry vs. Inferiority
11 - 18 yrs - Identity vs. Role Confusion
19 - 40 yrs - Intimacy vs. Isolation

Jean Piaget – Cognitive Development

• A comprehensive theory about the nature and development of human intelligence.

• children are driven by heredity and environment

• They construct knowledge actively as they manipulate and explore their worlds

Cognitive development theory

Sensorimotor Stage – Birth to 2 yrs
Preoperative stage – 2 to 7 yrs
Concrete operational stage – 7 to 11 yrs
Formal operational stage – 11 yrs to adulthood

Moral Development

• Moral reasoning, the basis for ethical behavior, has six identifiable developmental stages.

• He claimed that logic and morality develop through constructive stages.

• He theorized that the process of moral development was principally concerned with justice and that its development continued throughout the lifespan.

• Men use the “ethic of justice” (according to rules and rights)

• Women use the ethic of care (obligation to care and not to hurt)

Stages of Moral Development

Level I. Preconventional Morality

Stage 1. Obedience and Punishment Orientation: Obedience and Punishment

Stage 2. Individualism and Exchange : Individualism, instrumentalism and exchange

Level II. Conventional Morality

Stage 3. Social Conformity: “Good boy or good girl”

Stage 4. Maintaining the Social Order : Law and Order

Level III. Postconventional Morality

Stage 5. Social Contract and Individual Rights : Right action pertains to general individual rights

Stage 6: Universal Principles : Principled conscience

Stage 7: Transcendental Morality or Morality of Cosmic Orientation : Linked religion with moral reasoning

James Fowlers – Religious Development

It focuses on the meaning and purpose of one's life. It points to a way of “making sense of one's existence”

Stages of Faith Development

Level: Pre-Stage – Primal or Undifferentiated Faith

• Ages: 0 – 2

• Characteristics:

• Have the potential for faith but lack the ability to act on that potential.

• Through loving care from parents and other adults in their life young children start to build a lived experience of trust, courage, hope and love.

• At this stage, children experience faith as a connection between themselves and their caregiver.

Level: Stage 1: Intuitive-projective Faith

• Ages: 3 – 7 (Pre-School Age)

• Characteristics:

• The cognitive development of children of this age is such that they are unable to think abstractly and are generally unable to see the world from anyone else's perspective. As Robert Keeley writes: "These children cannot think like a scientist, consider logical arguments, or think through complex ideas."

Level: Stage 2: Mythic-literal Faith

• Ages: 6 – 12 (School Age)

• Characteristics:

• Children at this age are able to start to work out the difference between verified facts and things that might be more fantasy or speculation.

• At this age children's source of religious authority starts to expand past parents and trusted adults to others in their community like teachers and friends.

• Like the previous stage, faith is something to be experienced. At this stage it is because children think in concrete and literal ways. Faith becomes the stories told and the rituals practiced. Later in this stage children begin to have the capacity to understand that others might have different beliefs than them.

Level: Stage 3: Synthetic-conventional Faith

• Ages: 13 to adulthood (Teenagers)

• Characteristics:

• Unlike previous stages, people at this stage are able to think abstractly. What were once simple unrelated stories and rituals can now be seen as a more cohesive narrative about values and morals. With abstract thinking comes the ability to see layers of meaning in the stories, rituals and symbols of their faith. At this stage people start to have the ability to see things from someone else's perspective.

Level: Stage 4: Individuative-reflective Faith

• Ages: Mid 20s to Late 30s

• Characteristics:

• People in this stage start to question their own assumptions around the faith tradition.

• Along with questioning their own assumptions about their faith, people at this stage start to question the authority structures of their faith.

• This is often the time that someone will leave their religious community if the answers to the questions they are asking are not to their liking.

Level: Stage 5: Conjunctive Faith

• Ages: Midlife Adult

• Characteristics:

• People do not usually get to this stage until their early thirties.

• This stage is when the struggles and questioning of stage four give way to a more comfortable place. Some answers have been found and the person at this stage is comfortable knowing that all the answers might not be easily found.

• In this stage, the strong need for individual self-reflection gives way to a sense of the importance of community in faith development.

Level: Stage 6: Universalizing Faith

• Ages: Late Adulthood

• Characteristics:

• It is a rare person who reaches this stage of faith.

• People at this stage can become important religious teachers because they have the ability to relate to anyone at any stage and from any faith. They are able to relate without condescension but at the same time are able to challenge the assumptions that those of other stages might have. People at this stage cherish life but also do not hold on to life too tightly.

• I.e. Gandhi and Mother Teresa

Developmental Tasks

• The Havighurst theory was age dependent, and all served logical functions depending on their age.

• He recognized that each human has three sources for developmental tasks. They are:

• Tasks that arise from physical maturation: (Learning to walk, talk, control of bowel & urine, behaving in acceptable manner to opposite sex, adjusting to menopause)

• Tasks that arise from personal values: (Choosing an occupation, figuring out one’s philosophical outlook)

• Tasks that arise due to pressures of society: (Learning to read, learning to be responsible citizen)

Daniel Levinson - Four Eras of Life

• Childhood and adolescence: birth to 20

• Early adulthood: 17- 45
  establishes a distinction between the “me” and “not-me”; beginning of a more independent, responsible adult life that includes sexual maturity

• Early adult transition: 17- 22
  seeks independence by separating from family

• Entering the adult world: 22 - 28
  experiments with different careers & lifestyles

• Age thirty transition: 28 –33
  makes lifestyle adjustments

• Settling down: 33 - 40
  experiences greater stability

• Middle adulthood: 40 - 65

• Entering middle adulthood: 45 – 50

  neglected parts of self-seek expression, aware of death
   choices are made; commit to new tasks

• Age fifty transition: 50 –55

  evaluate the entire life structure

• Culmination of middle adulthood: 55 – 60
  opportunity to prepare self in order to carry out main objectives for the coming era.

• Late adulthood: 60+
  spends time reflecting on past achievements & regrets; makes peace with self and others

• Late adult transition: 60 – 65
  need to reduce the level of responsibility, less authority and power which needs getting used

Stephen Jay Gould - Seven Stages of Adult Development

• Believes that transformation is a central theme during adulthood

  1) 16 to 18 - want to separate from their family
  2) 18 to 22 - feel they could be pulled back into their family
  3) 22 to 28 - autonomous but still feel the need to prove themselves to their parents
  4) 28 to 35 - marriage & careers are well established; no longer feel necessary to prove self
  5) 35 to 43 - period of self-reflection; see time as finite, with little time left to shape lives of children
  6) 43 to 50 - interested in social activities with friends & spouse & desire both sympathy & affection from spouse
  7) 50 to 60 - period of transformation, with a realization of mortality & a concern for health; increase in warmth and decrease in negativism

Robert Peck Tasks of Ego’s Integrity

• Believes that although physical capabilities & functions decrease with old age, mental & social capacities tend to increase in the latter part of life.

1. Stage 1 Ego Differentiation vs. Work-role preoccupation
        o “Ego Differentiation” - A person finds new meaning and value in his or her life.
        o “Work Role Preoccupation” - defining oneself through work or an occupation
        - Upon retirement: - One role should replace the work role as a source of self-esteem on retirement
        - Establish new activities so that loss of accustomed roles is less keenly felt

2. Stage 2 Body transcendence vs. Body preoccupation
        o Body Transcendence - A person accepts the limitations that accompanies the aging process
        o Body Pre-occupation - dwells on diminishing abilities
          Therefore:
            - Individual should adjust to decreasing physical capacities & at the same time maintain feelings of well being

         - Select activities compatible with the physical limitations of old age.

3. Stage 3 Ego transcendence vs. Ego preoccupation
         o “Ego Transcendence”- person believes his or her life has worth and “life contributions” will live on after death
         o “Ego Preoccupation” - person feels that he or she has lived a useless life
            Thus:
            - Make contributions that extend beyond your own lifetimes, thereby providing a meaning for life.
            - Acceptance without fear of one’s death as inevitable and not to hold on to life because he lived a useless life; Self-examination occurs.