Chapter 2 - Introduction to Physical Changes
What are the physical changes in adulthood of those 18-24 years?
-Weight and body mass are optimal for most with 17% being obese. -Facial features and skin tone are youthful; hair is full. -Vision at its peak acuity; hearing may start to decline due to loud sports/music/leisure activities. -Bone mass is still building. -Neuronal development is completed. -Hormones are fully functioning; fertility is at optimal level. -Sexual response is at optimal level.
What are the physical changes in adulthood of those 65-74 years?
-Weight and girth begin to decrease in 70s. 1/3 are obese. -Wrinkles and loss of skin elasticity increase. -Vision loss continues, cataracts are common. Loss of tase and smell becomes noticeable, especially sweet and salty tastes. -Bone mass continues to decline. Risk for fractures increases esp. for women. -Neuronal loss continues. Some decrease of myelin and slowing of reaction time. Some decline in cognitive processes become apparent. -Hormones continue to decline. -Sexual responses continue to decline, through lack of partner is top reason for not having sexual relations.
What are the physical changes in adulthood of those 25-39 years?
-Weight and girth begin to increase around 30. 1/3 are obese. -Facial features remain youthful for most; some men begin hair loss. -Beginning of vision and hearing losses, declines in taste and smell, but not generally noticeable. -Peak bone mass reached at 30. -Some neuronal loss, but not noticeable. -Production of major hormones begins to decline but not noticeable. -Sexual responses begin to slow.
What are the physical changes in adulthood of those 40-64 years?
-Weight continues to increase until 50s, remains stable till 60; girth continues to increase and fat moves from extremities to abdomen. Over 1/3 are obese. -Skin begins to wrinkles and lose elasticity. Thinning of hair for men and women, more extreme for men. This is the largest age group for plastic/cosmetic surgery. -Near vision loss in 40s. Dark adaptation becomes apparent in 60s. Cataracts begin in 40s. Slight loss of taste and smell. Hearing loss is more noticeable. -Neuronal loss continues, especially in brain centres related to memory. Myelination and reaction times are peak. -Hormones continue to decline, fertility declines gradually for men; sharply for women after menopause. -Sexual responses become slower and less intense.
What are the physical changes in adulthood of those 75+ years?
-Weight gain and girth remain stable. About 15% are obese. -Wrinkles and loss of skin elasticity increase. -Visual and hearing losses continue. -Bone mass continues to decline. Risk for fractures increases sharply, especially for women. -Neuronal loss continues. Myeline decreases and cognitive processes show definite decline. -Continued low levels of major hormones. -Sexual responses continue to deline, though many continue to enjoy sexual relations throughout adulthood.
Modern Maturity Sexuality Survey
1,300 men and women from the ages of 45-94 were asked about sexual activity such as kissing and touching, sexual touching, oral sex, masturbation and intercourse. Besides sexual activity pertaining to age, physical ability, sexual desire, social surroundings and environmental aspects at different points in adulthood were examined.
What is the safe exposure time to loud noises?
1/4 hour or less to 115 decibels.
How many men make up plastic surgery patients?
10%
How much of the variation in total body weight is influenced by genetics?
60%
What are the hair loss statistics in the USA for men?
67% of men lose hair by the age of 35. 85% show significantly thinning hair by 50 years. 15,000 have had hair transplant surgery with 70% being over 55 years old.
How much sleep does the average adult get each night?
7 hours; 1/2 of all adults report sleep problems and 70% of emerging adults report not getting the recommended amount of sleep on school nights.
What is the most used hormone replacement regime?
A combination of estrogen and progesterone for women at menopause.
What promotes neurogenesis in aging animals?
A combination of physical exercise and cognitive stimulation.
Osteoarthritis
A condition caused by loss of soft cartilage that protects the bones of joints; can involve pain, swelling and loss of motion. Soft cartilage wears away with age and use. It allows bones to rub together causing pain, swelling and loss of motion at the joint. 27 million people in the USA have it, and most are over 65. Its more prevalent in females, and younger male adults are more apt to get it from work or sports injuries. Athletes are more likely to be at risk with prevalence depending on the sport played. It can lead to depression, anxiety, and feelings of helplessness, lifestyle limitations and loss of independence. Pain and stiffness can be relieved by medication and appropriate balance of rest and exercise/range of motion. Weight management also helps. Acupuncture, massage therapy, vitamins, and nutritional supplements. Injections of hyaluranic acid. Joint replacement is another option.
Obesity
A condition in which one's weight to height ration increases to a point that hans an adverse effect on health; usually measured in terms of body mass index (BMI). Almost 2/3rds of people in the USA are above optimal weight but over 1/3 are considered obese. 1/2 of the overweight people in the USA have a total body weight that puts them at risk for numerous health disorders.
What is primary aging due to?
A decline in hormone production.
Progeria
A extremely rare genetic disorder in which symptoms resembling aspects of aging are manifested at a very early age. Progeria is one of several progeroid syndromes. There are approximately 144 cases in the entire world. These people have the physical ability of the elderly yet cognition of a child. Progeria = advanced geriatrics A single genetic mutation which produces a toxic protein called progerin which accumulates in cells. Rapamycin (immune suppressant) is show to reduce progerin damage. Ex: Hutchinson-Gilford (Type of Progeria) Characterized by the dramatic, rapid appearance of aging beginning in childhood. Affected children typically look normal at birth and in early infancy, but then grow more slowly than other children and do not gain weight at the expected rate (failure to thrive). They develop a characteristic facial appearance including prominent eyes, a thin nose with a beaked tip, thin lips, a small chin, and protruding ears. Hutchinson-Gilford progeria syndrome also causes hair loss (alopecia), aged-looking skin, joint abnormalities, and a loss of fat under the skin (subcutaneous fat). This condition does not affect intellectual development or the development of motor skills such as sitting, standing, and walking. Physical symptoms include growth failure, loss of body fat and hair, stiffness of joints, atherosclerosis, skeletal abnormalities, "aged" skin. Death occurs from CVD on average at 13 years.
Middle Age Sleep Cycle
A lack of sleep due to health problems becomes a factor especially if weight has increased and activity level has decreased. Stress contributes to sleep problems at this age in addition to menopause which affects sleep with hot flashes. There is also an increase in sleep apnea.
Hyaluranic Acid
A natural component of cartilage and joint fluid.
Sleep Apnea
A pause in breathing during sleep due to constriction of the airway.
What to all the physical changes associated with aging combine to produce in addition to the loss of speed?
A reduction in stamina, dexterity and balance.
What are some factors that can contribute to primary aging?
A sedentary lifestyle, diet, alcohol, tobacco, and sun exposure.
What is the lid of the eye?
A sphincter muscle.
Aldosterone
A steroid hormone secreted by the adrenal glands. It serves as the principal regulator of the salt and water balance of the body and thus is categorized as a mineralocorticoid. It also has a small effect on the metabolism of fats, carbohydrates, and proteins. It decreases with age, leaving some older adults prone to dehydration and heatstroke when summer temperatures soar.
Is it possible to slow down the loss of telomere length in one's cells?
A study found that people who exercise will have significantly longer telomeres than those who don't. Heavy exercisers' telomeres could be compared to those 10 years younger who don't exercise. It suggested that exercise is beneficial.
Skin Aging From Twin Pairs
A study looking at skin aging found that for 130 pairs of twins ranging up to 77 years of age, they found that identical twin pairs were more alike in their facial skin aging patterns than fraternal twins and that genetic contribution to facial skin aging is about 60%. This means that 40% of our facial skin aging is due to other causes such as smoking or UV radiation.
Perceived aging
A study on twins having 20 nurses looking at photos and then estimating the ages of the twins found that the perceived ages of identical twins were significantly more alike than perceived ages of fraternal twins with 60% of perceived age being genetic and 40% to other factors.
Resveratrol
A substance found in red wine that extended the life spans of yeast, worms, and flies.
How many older men and women have oral sex?
A substantial number of men and women over 50 report oral sex, with 25% of men and 8% of women over 70 - 2012.
Presbyopia
A visual condition caused by loss of elasticity in the lens resulting in the inability to focus sharply on nearby objects. Reduced visual acuity or loss of near vision. Can be helped by prescription glasses or contact lenses.
Accomodate
Ability of the lens of the eye to change shape to focus on near or far objects, or small print. Around age 45, the lens of the eye, which has been accumulating layer of cells since childhood gradually loses elasticity, showing a sharp decrease in its ability to accommodate (change shape to focus). The loss further reduces overall visual acuity in middle aged/older adults.
Visual Acuity
Ability to perceive detail in a visual pattern.
Pruning
Ability to shut down neurones that are not needed in order to "fine tune" they system and improve functioning of the remaining neurons. Most pruning takes place in early infancy, but there is evidence that some neutron loss in old age may reflect this process. While there is a loss in the total number of neurons with age, not all the loss translates into functional decline.
Stamina
Ability to sustain moderate or strenuous activity.
What can chronic sleep deprivation lead to?
Accidents, heart disease, obesity, diabetes, cancer, mental disorders, and decrease in immune function.
Which portion of the population is slightly more likely to be considered obese?
Adults 60 and older. 1/3 of all adults and 17% of children have a total body weight that is considered a serious medical condition.
Senile Miosis
Affects the iris. Reduction in pupillary diameter with age. Much less light reaches the retina (60 year old receives 1/3 the light of a 20 year old). The pupil can't dilate in old age. Less light to the back of eye. Lessen/shortened response time. Changes from light to dark take longer to adjust (like going inside and out of a tunnel or dark to a light room)
DNA Damage - Genetic Cellular Theory
Aging results from damage to the genetic information involved in the formulation of cellular proteins (e.g. from mutations). Environmental toxins, etc. The rate of mutations too low to really be worrisome.
Error Theory - Genetic Cellular Theory
Aging results from errors involved in the transmission of information from DNA to the final protein via mRNA (faulty selection of amino acids such as thymine, guanine, adenine and cytosine); which are called transcription errors. Error occurring in a genuine. They replicate then replicate in error.
Accumulation - Non-Genetic Cellular Theory
Aging results from the accumulation of deleterious substances within the cell which interfere with cellular metabolism and ultimately may lead to cell death. (lipofuscin). Some evidence for this. Ex: garbage from cells doesn't get removed and then collects and builds up. Such as waste/hair etc going down a drain pipe. Human evidence example are cataracts.
What do studies show about sexual activity throughout adulthood?
Among people with regular partners the number is high with as much as 10 times or more per month. It drops to 3 times per month in 60s and 70s.
When is peak bone mass reached?
Around age 30, followed by a gradual decline in both men and women. But bone loss is greater in women.
Why is it likely that the immune system becomes weakened with age?
As chronic diseases become more prevalent and exercise and nutrition decline.
Iris
Because the iris is a muscular sphincter tissue dependent upon a risk but fragile vascular supply, it is especially susceptible to systemic senile changes. Ex: Senile Miosis
Why are so many visual impairments going without screening or treatment?
Because there is a lack of information about diagnosis and treatment, many people think that the eye exam during driving renewal tests screens for eye conditions (which it does not) and many people in the USA and around the world live in areas without access to eye-care specialists. Finally, many think that failing eyesight is an unavoidable part of growing older.
At what age does the ability to taste and smell begin to decline?
Beginning around age 30 and more noticeable around age 65-70. Over 2 million people in the USA have disorders of taste and smell and most are older adults. The risk factors are older age, males experience it more often, smoking, living in urban areas, and working in industries such as chemical or paper manufacturing.
Skin
Beginning around age 45 the wrinkles of the skin become evident, resulting in part from the redistribution of body fat. It also occurs because of a loss of elasticity, part of a pervasive loss of elasticity that affects muscles, tendons, blood vessels, and internal organs as well as skin. The loss of elasticity is especially notable in skin that has been continually exposed to the sun.
Historical Attempts to Deny Aging
Blood transfusions from young men - Pope Innocent VIII dies almost immediately. Monkey testicle tissue is graded on to young men who mostly develop syphilis - Russian surgeon Serge Voronoff. Cryogenics, freezing body in liquid nitrogen immediately after death so that you can be thawed at a later date. Frozen cells burst when thawed. Gerokomy, elderly males are encouraged to sleep between two female virgins which is supposed to restore the man's vigour but the consequences for female virgins remains unclear.
What is the major change involved in primary aging of the bones?
Calcium loss. It causes the bones to become less dense.
Hookups
Casual sex without commitment.
Eye Diseases
Cataracts: Affects 5-7% of adults over 65. Glaucoma: Intraoccular pressure.
Neurons
Cells in the brain and nervous system.
B Cells
Cells of the immune system produced in the bone marrow that manufacture antibodies. B cells show abnormalities with age, and have been implicated in the increase of autoimmune disorders in older adults.
T Cells
Cells of the immune system produced in the thymus gland that reject and consume harmful or foreign cells. With age, T cells show reduced ability to fight new infections.
Theory Of Genetic Limits
Centres on the observation that every species has a characteristic maximum life span. Appx maximum life span for humans is 110-120 years, longer and shorter for other mammals. These observations have led cellular biologist Hayflick to propose that there is a genetic program setting the upper age limit of each species. He showed that when human embryo cells are placed in nutrient solutions and observed over a period of time, the cells divide only about 50 times, after which they stop dividing and enter a state known as replicative senescence. Cells from the embryos of longer-lived creatures such as the Galápagos tortoise double perhaps 100 times, whereas child embryo cells double only about 25 times. The number of divisions a species will undergo before reaching replicative senescence is known as Hayflick Limit and that there is a positive correlation between that number and the species' longevity. According to the therapy, primary aging results when we approach the Hayflick Limit for the human species, exhausting our cells' ability to replicate themselves. The suggested mechanism behind the theory comes from the discover that chromosomes in many human body cells (and those of other species) have at their tips lengths of repeating DNA called telomeres which are necessary for DNA replication and appear to serve as timekeepers for the cells. Once telomeres are used up, the cell stops dividing.
Menopause
Cessation of a women's menstrual periods, occurring 12 months after the final menstrual period; climacteric.
Progeriod Disorders - Werner's Syndrome
Characterized by the dramatic, rapid appearance of features associated with normal aging. Type of Progeria. Individuals with this disorder typically grow and develop normally until they reach puberty. Affected teenagers usually do not have a growth spurt, resulting in short stature. The characteristic aged appearance of individuals with Werner syndrome typically begins to develop when they are in their twenties and includes graying and loss of hair; a hoarse voice; and thin, hardened skin. They may also have a facial appearance described as "bird-like." Many people with Werner syndrome have thin arms and legs and a thick trunk due to abnormal fat deposition. Physical symptoms include diabetes, cataracts, osteoporosis, atherosclerosis. Onset in early adulthood.
What does the loss in stamina result from?
Clearly arises in large part from the changes in the cardiovascular and respiratory systems.
Cross-Linkage - Non-Genetic Cellular Theory
Cross linkages, or bonds, develop between components of the same molecule or between molecules (ex: proteins such as elastin and collagen cross link with age). May be due to the effects of highly unusable chemical compounds called free radicals. Free radicals are highly unstable. Antioxidants combat free radicals.
What two hormones have been documented as having age related declines?
DHEA and GH. Animal studies suggest that replacing these hormones reverses aging and provides protection against disease. Results in humans have been mixed. Meta-analysis has shown small decreases in body fat and small increases in lean body mass but increased rates of adverse effects.
What are declining hormone levels in men associated with?
Decreases in muscle mass, bone density, sexual desire and cognitive functions and with increases in body fat and depressive symptoms.
DHEA
Dehydroepiandrosterone. Hormone involved in the production of sex hormones for both males and females. Widely used by adults of all ages in the USA as its considered a nutritional supplement.
Caloric Restriction (CR)
Diet in which calories are severely reduced, but containing essential nutrients; found to slow down aging in animal studies.
Does caloric restriction lead to longevity in life?
Early researchers found that animals put on restrictive diets that are 60-70% of normal diets but included all the normal nutrients, stayed youthful longer, suffered fewer late life diseases and lived significantly longer than normally fed counterparts. Animals on caloric restriction show a lower incidence of age related disease including type 2 diabetes, cancer, heart disease and brain atrophy. To receive maximum benefits we'd have to decrease our intake by 30% which is difficult to sustain. There are some positive health benefits such as protection against type 2 diabetes and heart disease and a reduction in cancer/cancer deaths. The downfalls are cold intolerance, increases in stress hormones, decreases in sex hormones, and physiological effects of extreme hunger - obsessive thoughts about food, social withdrawal, irritability and loss of interest in sex.
Sexual Partner
Emerging adults have more hookups/casual sex without commitment. Middle aged and older adults want more commitment with sex.
Myelin
Fatty substance that insulates and protects the neuronal axons and is a major component of the white matter of the brain. Aides in the processing speed of information along the neuron, and its formation begins shortly after birth. Myelin increases with age throughout childhood and early adulthood, peaks in middle age, and then rapidly decreases in old age.
Estrogen
Female sex hormone.
Progesterone
Female sex hormone.
What has research over the last few decades given us regarding primary aging?
First, that it can be differentiated from dispatch, and second, that there are many different "normal" timelines for primary aging.
GH
Growth Hormone. Synthetic version of human growth hormone that is prescribed for a limited number of conditions but widely used as an anti-aging drug. Widely available in the USA but it needs to be prescribed by a doctor and the FDA hasn't approved it as an anti-aging drug.
Neurogenesis
Growth of new neurons. It involves the production of stem cells, which are immature undifferentiated cells that can multiply easily and mature into many different kinds of cells.
What is some of the evidence for primary aging?
Hayflick Limit: Number of cell divisions @ 50. Telemeres: Telomerase - enzyme which replenishes telemeres. (Like the plastic cap on the end of a shoelace). Telemeres shorten and eventually cell division stops. Negative Pleiotropy: Genes which trade off early life benefits (high fecundity rates) with late life disadvantages (increase in cancer rates). There are pros and cons. The same gene can give you ability early in life such as a survival advantage, but later on be a detriment. Monozygotic Mortality Concordance Rates: Identical twins die closer together in time than fraternal twins. There is genetic evidence for this. Daf-2 Mutation: Encodes a hormone receptor. If you make a mutation in the daf-2 gene cell, that you get a receptor that doesn't work as well; the animal lives longer. So that means that the normal function of this hormone receptor is to speed up aging. Daf-2 gene codes for other hormones that are important - encodes a hormone receptor. Gene for aging. C.elegans. If Daf-2 is damaged worms were living twice as long. Foxo3A protein turns on genes that extend life span, cell protection and repair.
What can one do if hearing loss becomes a problem?
Hearing aids that feature digital technology, directional microphones, feedback control devices, and programs for listening to music or conversations. They amplify and direct sound to better its chance of being picked up by the impaired hearing system. When severe, cochlear implants can be used which are a surgical procedure that allows sound waves to bypass the hair cells and go directly to the acoustic nerve.
What is the most frequent sensory disability?
Hearing loss.
Stem Cells
Immature undifferentiated cells that can multiply easily and mature into many different kinds of cells.
What changes in oxygen uptake as we age?
In a study of male athletes, the athletes trained for endurance sports had significantly higher levels of oxygen uptake than those trained for speed-power sports. Both types of athletes have significant higher oxygen uptake levels than nonalthletes at all age levels. While oxygen uptake declines in all men with age, the differences continue between the studied 3 groups, with some trained athletes in their late 80s still testing higher than some non athletes in their 20s. We slow down as we age, but when one exercises and is in better shape, they stay ahead of those who have never trained/exercised.
Insomnia
In ability to have normal sleep patterns. Increases with age and affects more women than men. There are 3 major causes: 1) Predisposition. 2) Outside factors such as disease, medication, depression, anxiety, and stress. 3) Lifestyle factors such as alcohol use, caffeine, lack of exercise, daily napping and blue-screen electronic devices before bed and during the night.
Plasticity
In neurons, the ability to form new connections or grow new extensions. Neurons are capable of making changes with age. Neurons form new connections with other neutrons, change thresholds and response rates, and take over the functions of nearby neutrons that have been damaged.
How does the immune system protect the body?
In two ways: 1) Through B Cells which is produced in bone marrow make proteins called antibodies which react to foreign organisms such as viruses and other infectious agents. 2) T Cells which is produced in the thymus gland and rejects and consumes harmful or foreign cells such as bacteria and transplanted organs.
Sensorineural Hearing Loss
Inability to discriminate between loud and soft sounds caused by damage to the receptors in the inner ear. Caused by damage to the tiny hairs inside the cochlea.
Presbyopia
Inability to focus near objects.
Immunological Theory - Physiological
Infectious microorganisms (ex: fungi, bacteria, viruses) have unique proteins on their surfaces called antigens - the immune system produces antibodies which recognize specific antigens and help destroy them. Autoimmunity increases with age. Ex: Multiple Sclerosis and autoimmune disorders.
Resistance Training
Involves contracting muscles by lifting or pushing and holding the contraction for up to 6 seconds.
Macular Degeneration
Irreversible loss of nerve cells in retina. There are two forms: wet and dry. Dry is gradual. Dry is 90% of cases and is proliferation of new blood vessels or seeping blood. It is different than tunnel vision, its the opposite. its irreversible, can be caused by nutritional deficits or exposure to UV rays.
Postmenopause
Is the time after a women has not had a period for 12 months and extends until the end of her life.
How many men and women over the age of 70 masturbate?
It is estimated that 1/3 of women and 1/2 of men between the ages of 70 to 94 masturbate - 2008.
What is speculated to be the slowdown of cognitive speed found in old age?
It may be caused more by the breakdown of myelin - white matter of the brain, than the loss of neurons - the grey matter. The gradual breakdown of myelin seems to be a part of primary aging, but it can also be exacerbated by brain trauma, hypertension, diabetes, high cholesterol, and substance abuse.
Vitreous Humor
Largest part of the eye; gives the eye its spherical shape due to its mostly gel like nature (jelly like). It can shrink, become more fluid, and pull away from retina possibly producing blurred vision. Ex: It is associated with truck drivers who do long distance driving. "Floaters" (suspended waste material) are mostly annoying rather than functional decline (little black dot floating in vision).
Stretching
Lengthens muscles and increases flexibility. Stretching should be held for 5 seconds initially and up to 30 seconds with increased practice. Stretching in water is easier as it supports body weight and provides more resistance than stretching on land.
Telomeres
Lengths of repeating DNA that chromosomes have at their tips. Necessary for DNA replication and appear to see as timekeepers for cells. On average, telomeres in cells of middle-aged adults are shorter than those of young adults. The telomeres of older adults are shorter still. Once telomeres are used up, the cell stops dividing. Telomere lengths for males and females are the same at birth, but by adulthood, they are longer in females than males. Length has been related to both primary and secondary aging. People who are at high risk for heart disease or type 2 diabetes have shorter telomere lengths than healthy adults their age. It has also been related to chronic stress conditions.
Why do people lose the ability to taste and smell?
Less salvia is found in older people which reduces the release of molecules in food to be sensed by taste buds. There are fewer taste buds - appx 1/2 as many at age 70 as there is at age 20. Those that detect sweet and salty decline more rapidly making people salt their food or sweeten their coffee at greater extents which has its own set of issues surrounding that. There is also a decrease in the number of odour receptors in the nose as we age.
Heyflick Limit
Maximum number of times cells are programmed to divide for a species.
Bone Mass Density (BMD)
Measurement of bone density used to diagnose osteoporosis.
Who makes up the largest population of people who get plastic surgery and minimally invasive procedures?
Minimally Invasive: 40-54 year olds at 48% Cosmetic Surgery: 40-54 year olds at 33% Mean
Free Radicals
Molecules or atoms that possess an unpaired electron; by-products of cell metabolism.
Hearing
Most adults begin to experience some hearing loss in their 30s. Mainly of the higher tones. There is also a shortening of the "loudness scale" which is confusion between loud tones that are not being heard as well as before and softer tones that are still being heard accurately. Without the loud-soft discrimination, its difficult to perceive which sounds are coming from nearby or far away. By age 65 about 1/3 of adults have some significant hearing impairment and the numbers rise sharply thereafter. The best prevention for loss is to limit exposure to loud noise. There has been a 20% increase in the last decade in the prevalence of hearing loss among people 18-19 year olds. Likely due to MP3 players.
Does aging mean deterioration of the brain?
No. New technology shows that the loss of neurons (brain cells) in primary aging is much less severe than once thought. The nervous system is plastic - neurons are capable of making changes with age. In addition, pruning which is the ability to shut down neurons that are not needed in order to fine tune the system and improve functioning of remaining neurons. Neurogenesis also occurs throughout adult years - primarily in the dentate gyrus which is a small area of the hippocampus and crucial for forming memories. Neurogenesis continues well into older adulthood, but the rate at which neurons are produced slows down as we age, presumably leading to age-related cognitive loss.
Body Mass Index (BMI)
Number derived from a person's weight and height; a standard indicator of body composition. BMIs under 19 are considered underweight, 19-24 is considered normal, 25-29 is overweight and 30+ is obese. Its not a perfect system because people who are very muscular would be considered overweight based on their overall body weight and height.
Oxidative Damage
One theory of primary aging is based on random damage that takes place on the cellular level. Identified by biogerontologist Denham Harmon in 1956, involves the release of free radicals, molecules or atoms that possess an unpaired electron and are by products of normal body metabolism as well as a response to diet, sunlight, x-rays, and air pollution. The molecules enter into many potentially damaging chemical reactions, most of which the healthy body can resist or repair, but as we age our resistance and repair functions decline. the oxidative damage increases and the result is primary aging. But we still can't say that it causes aging. Its a factor involved in primary aging.
How many men have lower than normal testosterone levels?
Only about 20% of men over 60.
Pupil
Opening in the eye that changes in diameter in response to available light. They lose their ability to open efficiently in response to reduced light. The result is the older we get, the less light that gets from the pupil to the retina.
Rapamycin
Originally found in soil collected on Easter Island, it inhibits cell growth and was first used as an anti-rejection medication for organ transplant patients. Studies show it extended the maximum life span of mice by some 12% including mice who were the equivalent of 60 years of age in humans. It works to block the effects of a protein called TOR, which scientists believe is implicated in many age related diseases and perhaps primary aging itself. TOR has the effect of sensing the availability of food in the organism, and in time of abundance, it becomes active and directs cell metabolism and division. One result seems to be increased longevity. The side effects have made it ruled out for human consumption.
Osteoblast vs. Osteoclast
Osteoblast is a cell which takes extra calcium from bloodstream and puts it in bones. Osteoclasts extract from bones when low in calcium. Can cause osteoporosis.
Ear Structure
Outer ear - Pinna: Like an antenna for sound collection. Fleshy part of ear and continues to grow with age. Indentations in ear also flatten as we age. Middle ear - contains the Tympanic Membrane (eardrum) and Ossicles (3). Ossicles are like mechanical gears and are the 3 smallest bones in the body. Inner ear - contains the Cochlea (organ of Corti). As we age there is hair cell loss in the Basilar membrane. There are high frequency constraints (z, g, s, f and t) become more difficult to discriminate. Ex: loud sound on Granville strip. 20-20,000 Hertz/second (wavelengths). Loss of it is like osteoporosis. Calcium loss in the bones.
What is the main cause of menopause?
Ovarian failure leading to a drop in estrogen and complex changes in progesterone - both important in women's reproductive health.
Primary Aging
Physical changes that are gradual, shared, and largely inevitable as people grow older. Changes in the major systems of the body that most adults experience as they age.
Secondary Aging
Physical changes that are sudden, not shared, and often caused by diseases, poor health habits, and environmental events as people grow older.
What does fovea mean?
Pit
Testosterone Replacement Therapy
Popular among middle-aged and older men in the form of injections, skin patches, and gels applied to the underarms. The benefits and risks of long term testosterone replacement therapy (over 3 years) is unknown at this time. However, 20% of men have taken the therapy and have had some increased bone mineral density and improved sexual function without adverse effects.
What does the loss in dexterity result from?
Primarily as a result of arthritic changes in the joints.
Primary vs. Secondary Aging
Primary aging includes changes over which we have little or no control. Which includes universal, gradual and endogenous (within/internal cause) changes. Primary Aging is also called Senescing. -Universal changes are those that happen cross culturally such as wrinkles (however wrinkles can also be secondary aging if a person laid outside in the sun a lot). -Gradual changes are those that are not sudden, you don't typically notice them. They are different from diseases. -Endogenous changes are those which are internal/within one's own biological system. Secondary aging is neither universal nor inevitable. These changes are due to disease, disuse and abuse. -Diseases such as cancer (but this isn't inevitable as not everyone gets cancer). -Disuse meaning atrophy. When one does not use a skillset such as not exercising or stopping eating healthy. Not keeping one's mind stimulated is also disuse. -Abuse consists of things such as smoking, alcohol abuse, drug use, going to loud parties or concerts, or taking part in extreme sports which are tough on the body.
What are the two processes of aging?
Primary and secondary aging.
Aqueous Humor
Principle means of transport for nutrients and metabolic waste to and from the lens (which is a sphincter muscle and avascular). As we age (primary aging), changes in the dynamics of aqueous production and drainage may be important factor in the genesis of glaucoma. Pressure builds up if waste isn't removed; will push against lens, cornea, and can become glaucoma (secondary aging).
Antibodies
Proteins that react to foreign organisms such as viruses and other infectious agents.
How does race, ethnicity and socioeconomic groups contribute to primary aging?
Race and ethnicity are risk factors for many conditions with primary aging such as obesity, glaucoma, macular degeneration and osteoporosis but when you as SES factors more differences emerge. Many factors that determine the rate of primary aging depend on education and income levels. Healthy eating requires nutrition information, exercise takes time, and screening and treatment are difficult to afford. Low income neighbourhoods are food deserts and the residents have limited access to fresh fruits and vegetables. Food is expensive, and residents have limited access to transportation to shop elsewhere. Lower levels of education and lower income equates to limited access to medical and dental care and prescription drugs. Black and Hispanic Americans are more likely to be shut out than Caucasians from forms of health care.
Taste Buds
Receptor cells for taste found on the tongue, mouth and throat. They specialize, responding to sweet or salty tastes (front of tongue), sour (sides), or bitter (back).
Replication of DNA
Replaces the nucleotide cytosine with the nucleotide thymine at position 1824.
What two types of exercise help rebuild muscle mass and strength?
Resistance training and stretching.
Caloric Restriction Theory of Primary Aging
Says our longevity is controlled by the number of calories we metabolize in our lifetime.
Oxidative Damage Theory Of Primary Aging
Says we age as a result of damage from free radicals that are released during normal cell metabolism.
Genetic Limits Theory Of Primary Aging
Says we age because our cells are programmed to stop dividing once we've reached a certain age.
Glaucoma
Second most common age-related condition. A visual disorder characterized by a buildup of pressure inside the eye that can lead to blindness if not treated. It can eventually destroy the optic nerve and lead to blindness. It is the second leading cause of blindness in the USA the first leading cause of blindness for people with African descent. It can be treated with eye drops, laser treatment or surgery, but it first needs to be detected. Its estimated 2 million people in the USA have the condition but only 1/2 are aware they have it. It can be detected as part of an eye routine examination and recommended that people in high-risk groups be screened at age 40. Everyone should be screened at 60. Risk factors are increased age, family history or African or Mexican ancestry.
Osteoporosis
Severe loss of bone mass. Makes the bones more likely to break than those of a younger person. It is based on a measure of bone mass density (BMD) which is easily determined by a test called a DXA scan (dual-energy X-ray absorptionmetry scan) of the hips and spine. The results are compared to those of a young healthy person. BMD measures at either the hip or spine which are more than 2.5 standard deviations below normal is considered osteoporosis. It affects 16% of women and 4% of men over 50. The biggest problem caused by osteoporosis is the increased risk of injury after a fall. It can result in serious injury, disability, loss of independence, and death. Typical breaks are wrist, spine, and hip. Risk factors are increased age, family history, female gender, European, Asian or Latin ancestry, history of earlier bone fracture, sedentary lifestyle, smoking, excessive alcohol consumption and underweight BMI. Treatments are routine examinations, vitamin D, estrogen and drugs that increase the effects of estrogen and restore lost bone integrity such as Fosomax, and patient adherence to their treatment.
When do most people notice a downturn in athletic ability?
Shortly after high school years.
Dexterity
Skill and grace in physical movement, especially in the use of the hands.
Cochlea
Small shell-shaped structure in the inner ear containing auditory receptor cells. This mechanisms is responsible for picking up sound vibrations and turning them into nerve impulses that will be transmitted to the hearing centres in the brain.
Olfactory Membrane
Specialized part of the nasal membrane that contains olfactory receptor cells. The sense of smell takes place here, and consists of millions of receptors and thousands of different kinds of cells. The variety allows people to experience subtle and complex flavours.
Enhanced Auditory Processing
Speech is supported by context. As we age we can have difficulty understanding conversations and we have to make inferences - fill in gaps of what we don't hear. To eliminate we need to remove background noise, don't jump from topic to topic, talk slower and not patronizing, and raise voice volume.
Replicative Senescence
State in which older cells stop dividing.
Retina
Structure at the back of the eye that contains receptor cells. Photosensitive layer at back of eyeball. Rods (dark and details) which are located in periphery and Cones (light) are located in fovea are the photoreceptors. There is a loss of photoreceptors (especially Cones from 40-60 years old) and atrophy of retinal capillaries as we age. Less light gets to this area as we age. By age 60, 1/3 of the light reaches this area than it did during the 20s.
Marriages and Sex
Studies have found those who married out of love report stronger sexual desire and more frequent sex. Having a happier marriage is related to more frequent sex.
How many people seek treatment for sexual problems as they grow older?
Studies have shown somewhere between 10% to 40% of middle aged and older adults have sought treatment and over half from their primary care physician. A wide range.
Changes in Body Weight
Studies of adults in the USA show that changes in total body weight follow a pattern over adulthood. It rises in 20s to 40s, saying level into the 50s and 60s and then declines in the 70s. The upward swing in weight during adulthood and middle age can be attributed to the human tendency to become more sedentary during that time without changing eating habits to compensate. The downward turn that takes place later is due to loss of bone density and muscle tissue.
Cyclic GMP
Substance released by the brain during sexual arousal. Part of its job is to close down the veins of the penis that normally drain blood so that the blood supply increases and tissues become engorged and erect. When in short supply, the result is erectile dysfunction. Drugs have been developed which magnify the effects of cyclic GMP such as Viagra (sildenafil citrate), Levitra (vardenafil) and Cialis (tatalafil). All give a wider window of opportunity in the timing of sexual activity.
Antioxidants
Substances that protect against oxidative damage from free radicals. A number of vitamin and vitamin like substances. Some are Vitamin E, C, Coenzyme Q10, beta-carotene, and creatine. There is no evidence they can delay primary aging or extend the life span.
What did researchers find out about nutritional supplements and their psychological effect?
That they can have an ironic effect. People who take supplements were more apt to express favourable opinions about hedonic actives such as casual sex, excessive drinking and partying instead of healthy activities such as yoga and exercise. They also scored higher on a test of perceived invulnerability. These supplements can make people indulge in unhealthy behaviours.
How many visual impairments can be prevented or cured?
The WHO estimates over 80%.
Dark Adaptation
The ability of the pupil of the eye to adjust to changes in the amount of available light. This process begins around age 30, but most people experience a marked decline after age 60. It causes minor inconveniences such as difficulty reading menus in dimly lit restaurants or finding seats in a dark movie theatre. There can be issues with driving at night. This is one of the reasons older people prefer attending matinee performances or making early dinner reservations.
Balance
The ability to adapt one's body position to change. Has practical ramifications when it declines. Older adults have greater difficulty handling uneven sidewalks or snowy streets, or a swaying bus. These situations require flexibility and muscle strength which both decline with age. There is a greater incidence of falls among the elderly due to the loss of steady balance.
Neuroendocrine Theory - Physiological
The coordination and regulation of the hormonal system by the brain degrades over time (production and release of testosterone, estrogen, growth hormone) decline with age. Involves the HPA axis (ex: secretion of glucocorticoids) under stress. HPA: hypothalamus pituitary adrenal
What do neuron bodies comprise?
The gray matter of the brain.
Erectile Dysfunction (ED)
The inability to have an erection adequate for satisfactory sexual performance. A common sexual problem in men and occurs in appx 30 million men in the USA with over 1/2 over 65 years old. It is associated with age, occurring in 5% of men between 40 and 65, and 25% of men over 65. It occurs for many reasons; heart disease, diabetes, excessive alcohol consumption, medication and smoking. The underlying mechanism seems to be similar in most cases - a shortage of cyclic GMP.
Vision
The last sense to develop in infants and the first to show signs of decline in middle age. It is also the sensory system that has the most complex structure and function, and has the most that could go wrong. Declining vision can be limiting to older adults with a loss of freedom, independence and status. Its associated with many other problems in adults such as falls, trips, stress and depression.
What is the problem with cellular phones and tablets during the evening?
The light mimics daylight and confuses circadian rhythms similar to jet lag. Adolescents and emerging adults are extremely sensitive to this resulting in insomnia.
What is the respiratory system made up of?
The lungs and the muscles involved in breathing. This system weakens with age, but in deathly people who don't smoke, it functions well enough to support daily activities. A difference in functioning is noticed when presented with vigorous exercise or high altitudes.
How do most adults experience a gradual decrease in muscle mass and strength?
The number of muscle fibres decreases probably as a result of reduced levels of growth hormones and testosterone. Another normal age related change is muscles slowly lose their ability to contract as quickly as they did at younger ages. Older people don't regain muscle mass as quickly as younger people after periods of inactivity such as when recovering from illness or injury. Many have adequate muscle strength to attend to the tasks they need to do and some stay at high levels of functioning as master athletes.
What are the proportion of people in the USA with high blood pressure?
The proportion increases with age for both men and women. The proportion is lower for women until around age 45, then becomes equal to men around 45-64, then higher than men after the age of 64.
What is an obvious change in the neuroendocrine system that is more obvious during aging?
The reduction of hormones that results in loss of reproductive ability, a time of life known as the climacteric.
Why do women experience greater bone loss/calcium loss?
Their bones are smaller and contain less calcium. The decline isn't equal between men and women - women's bone loss rate shows a marked acceleration between the ages of 50 and 65 and men's is more gradual.
Hormone Replacement Therapy
Therapy in which women take estrogen and progestin and menopause to replace hormones once produced by the ovaries; relives menopause symptoms. It provides perimenopausal and postmenopausal women with alleviations in hot flashes, vaginal dryness, and bone fractures. But its also been related to an increased risk of breast cancer, heart attacks, stroke and blood clots in certain high-risk groups.
Weight and Aging
There are changes in where weight is distributed starting in middle age where fat slowly leaves the face and extremities and begins to accumulate around the abdomen. There is a loss of plump cheeks and lips, a loss of protective padding on the soles of the feet, and a gain in waistline circumference.
Emerging Adult Sleep Cycle
They have sleep/wake cycles that are about 2-3 hours behind that of older adults, making them night owls who don't get sleepy until late at night and then don't feel wakeful until midmorning. Researchers say this is a normal developmental phenomenon.
Older Adult Sleep Cycle
They sleep about 1 hour less than younger adults, waking an hour earlier on average. But they are slo more apt to take naps during the day. Sleep problems can be the effect of physical and mental disorders and medication. Sleep patterns change in old age but it doesn't man that insomnia is the problem, its the health problems and medications which increase with age and the time spent exercising decreases.
Climacteric
Time of life for men and women that involves the reduction of sex hormone production resulting in the loss of reproductive ability. Takes place gradually for men over middle and late adulthood and more abruptly for women around the late 40s early 50s. In men the quantity of viable sperm produced begins to decline during their 40s but its not a rapid decline. The testes shrink gradually and after about age 60 the volume of seminal fluid begins to decline. It is associated in part with testicular failure and resulting gradual decline in testosterone. In women, menstrual periods become irregular, then further apart, then stop altogether. Menopause, peremenopause, perimenopause and post menopause are significant markers for women during this time.
Cornea
Tough transparent outer surface of eyeball; refraction of @ 2/3 of light rays. As we age, there is some flattening, some yellowing (certain light rays/bandwidths are filtered out), and there is a decrease in phasic lacrimal output (tearing). The cornea bends light rays/refracts. The outer area of the eye bulges to refract rays. It is like a microscope, the fine and strong knobs, the strong knob adjusts light rays.
Lens
Transparent structure in the eye that focuses light rays on receptors in the retina. Composed of clear, crystalline protein which encapsulates the lens. It provides fine tuning for focusing. It is avascular which means no blood vessels. It grows at a constant rate throughout life; dead cells become compacted at centre of lens. This can cause cataracts. As we age there are losses in transparency, yellowing and decrease in accommodative power (it can't change its shape as well.) During normal aging, the lens of the eye gradually thickens and yellows.
Retin-A
Tretinoin
When do changes begin in the hormonal system begin?
Usually around age 30. Growth hormone decreases with age, reducing muscle mass.
What is the second most feared disability?
Vision Loss
Cataracts
Visual disorder characterized by gradual clouding of the lens in the eye. Images are no longer transmitted sharply or in accurate colour to the retina. The most common eye disorder found in adulthood. More than 1/2 of adults over 80 have cataracts or have had them surgically removed. It is a major cause of vision loss in the USA and the leading cause of blindness in the world. The procedure involves removing the cloudy part of the lens and implanting an artificial lens that can be designed to correct visual acuity. Cataract surgery is the most common surgical procedure in the USA with 1.5 done each year. Risk factors are increased age, family history, female gender, diabetes, sunlight exposure and smoking.
Macular Degeneration
Visual disorder of the retina, causing central vision loss. The cause of the disorder is not fully clear, but its prevalence is. Symptoms of macular degeneration appear in appx 10% of people 66-74 years of age and 30% of people 75-85 of age. Vitamin therapy and laser treatment have shown promising results and rehab interventions have helped people with low vision to function. Risk factors are increased age, family history, European ancestry and smoking.
What are some age-related changes within the cardiovascular system?
When challenged such as during heavy exercise, the older heart is slow to respond to challenged and can't increase its function. Another change is that the walls of the arteries become thicker and less supple, so they don't adjust to changes in blood flow as well as younger adults. The loss of elasticity can cause hypertension (high blood pressure) which is more prevalent in older people.
White Matter vs. Gray Matter
White matter is found in the deeper tissues of the brain (subcortical). It contains nerve fibers (axons), which are extensions of nerve cells (neurons). Many of these nerve fibers are surrounded by a type of sheath or covering called myelin. Myelin gives the white matter its color. It also protects the nerve fibers from injury. Also, it improves the speed and transmission of electrical nerve signals. By comparison, gray matter is tissue found on the surface of the brain (cortical). It contains the cell bodies of neurons, which give gray matter its color. White matter - myelin; Gray matter - neurons. White matter may be as important to development as gray matter. The developmental timing of white matter more closely fits the changes we experience in our cognitive, behavioural and emotional abilities over the life span than the developmental timing of gray matter. White matter makes the major difference between human brains and those of other primates. This leads scientists to suggest that myelin underlies our human thinking processes such as consciousness, language, memory and inhibitory control.
Premenopause
Woman has regular periods, but hormone levels have begun to change.
Perimenopause
Women begins to have irregular periods but has had a period in the last 12 months.
Physical Changes (Sexuality)
Women: Decreased blood flow to genitals. Lower levels of estrogen and testosterone. Thinning of vaginal lining. Loss of vaginal elasticity and muscle tone. Men: Decreased blood flow to genitals. Lower levels of testosterone. Less penis sensitivity.
Changes in Sexual Desire
Women: Decreased libido. Fewer sexual thoughts and fantasies. Men: Decreased libido. Fewer sexual thoughts and fantasies. Young adults report loss of desire due to career pressure and parental responsibilities are at their peak. Middle aged adults report increased sexual desire when the day to day responsibilities of parenting end. Older adults report loss of desire because they believe sex is only for young people. Sex is highest in emerging adulthood and declines with age as part of primary aging. Lack of physical ability is the major sex-related complaint of men, lack of desire for women. Desire is driven by testosterone in both men and women. Reduced desire can lead to less interest, briefer sex, and less pleasure orgasms for women. Testosterone replacement therapy helps.
Changes in Orgasm
Women: Less intense. Vagina contracts and expands in 4 to 5 smooth rhythmic waves occurring at 0.8 second intervals when compared to 8-10 waves at 0.8 second intervals in younger women. Uterus contracts and is sometimes more painful. Men: Less intense. Urethra contracts in 1 to 2 waves at 0.8 second intervals instead of 3 to 4 waves at 0.8 second intervals in younger men. The semen can travel 3 to 5 inches after expulsion when compared to younger men. Smaller volume of semen.
Changes in Sexual Resolution
Women: Return to prearousal stage is more rapid when compared to younger women. Men: Return to prearousal stages takes only a few seconds over younger men which can take minutes to hours. More time between erections.
Changes in Sexual Excitement
Women: Slower arousal. Vaginal lubrication takes 1-5 minutes when compared to 15-30 seconds in younger women. Men: Greater difficulty achieving an erection. Erection after stimulation takes 10 seconds to several minutes when compared to younger men where it takes 3-5 seconds. Erections not as rigid.
Changes in Sexual Plateau
Women: Vagina doesn't expand as much. Less blood congestion in the clitoris and lower vagina. Diminished clitoral sensitivity when compared to response of younger women. Men: Pressure for ejaculation is not felt as quickly (compared to younger men).
How many hours of sleep do people need?
Younger adults - 8.5 hours. Older adults - 7.5 hours.
