Download Chapter 14 Stress and Heath

Chapter 14
Stress and Heath
•
•
•
•
•
•
•
•
•
Thursday, March 2
Friday, March 3
Monday, March 6
Tuesday, March 7
Wednesday, March 8
Thursday, March 9
Friday, March 10
Monday, March 13
Tuesday, Mar 14
531-539
1 in-class essay – clean prompt/no cards
chapter 13 Quiz
539 – 546
546 - 555
555 – 565
2 in-class essays – clean prompt/no cards
565 – 573
Quiz/Cards/St Guide
Stress (531)
• Stress - the process by which we perceive and
respond to certain events, called stressors, that we
appraise as threatening or challenging. Stress is
not just a stimulus or a response.
• Stressors can be perceived as challenges that
motive/arouse us or as threats that harm us and
lead to things like PTSD and physical health
problems.
Behavioral medicine (531)
- interdisciplinary
field of
psychology and medicine
Stress Response System (533)
• Walter Cannon - 1920 physiologist - identified the stress
response as part of a unified mind-body system
• stressors trigger the release of stress hormones epinephrine
(adrenaline), norepinephrine (noradrenaline) and cortisol.
• The stress hormones enter the bloodstream from
sympathetic nerve endings in the adrenal glands. The
sympathetic nervous system also increases heart rate and
respiration, diverts blood from digestion to the skeletal
muscles, dulls pain and releases sugar and fat from body
stores -------- all of this prepares the body for FIGHT or
FLIGHT
Fight or Flight AND (533)
There are alternatives to Fight or Flight:
withdraw (freeze)
seek and give support
Failure Turns Into Success (534)
• Hans Selye, a Canadian scientist, was researching
a new sex hormone - he injected rats with the new
hormone and observed enlargement of the adrenal
cortex, shrinking of the thymus gland and bleeding
ulcers. When he injected the rats with another
substance he found the same 3 responses - so he
had to conclude that the new hormone was not
causing the responses.
• So, >>>>>>>>>>>>>>
Failure Becomes Success
• At first Selye was depressed about his
failure - but then he thought that if he
considered the body's nonspecific reaction
to any damage - that he might be on to a
discovery! He experimented with other
stressors and indeed found that the body's
adaptive response to stress was so general
that he called it the General Adaptation
Syndrome
Selye’s General Adaptation
Syndrome (534)
The General Adaptation Syndrome has 3 stages:
1.
Alarm reaction due to the sudden activation of
the sympathetic nervous system
2.
Resistance - your functions remain high as you
fight
3.
Exhaustion - stress depletes your body's
reserves - you are more prone to illness during this
stage
Long-Term Stress (535)
• Human's cope well
with temporary stress,
but, prolonged stress
can cause physical
deterioration. -------MRIs show shrunken
hippocampus (new
memory formation
centre) of patients
with prolonged stress.
Stressful Life Events (535)
1. Catastrophes
2. significant life
changes
3. daily hassles
Catastrophes (535)
• Unpredictable
• large scale
• almost everyone appraises
them as stressors/threats
• significant health
consequences follow
prolonged stress - after
9/11 sleeping pill use rose
28% in New York
• depression and anxiety are
typical after a catastrophe
Significant Life Changes (536)
• see p 332 of Engel text for
Homes and Rahe theory
• Death, job, marriage,
divorce
• young adults are hardest
hit because they
experience most change
• disease often follows a
significant life change - a
widow's risk of death
doubles in the week
following the loss of the
spouse
Daily Hassles (536)
• Our happiness is more
affected by our response
to daily events than from
enduring good fortune
• Everyday hassles are a
significant cause of stress
because they add up and
take a toll on our health --- ie high blood pressure is
higher in congested urban
areas
Perceived Control (537)
• Catastrophes, significant life changes and daily hassles are
more stressful when we appraise them as both negative and
uncontrolled
• Weiss, 1977 - The executive rat can turn off the shock the subordinate rat cannot. The control rat is receiving no
shock. FINDING? The executive rat is no more likely to
develop an ulcer than the control rat.
Perceived Control (537)
• In humans a bacteria
infection plus
uncontrollable stress cause
the most severe
ulcers. Antibiotics will
kill the bacteria but stress
must be reduced to stop
the acid secretions.
• Executives outlive
clerical and labourers
because they perceive
more control.
Poverty and Inequality (537)
• Wealth also often means control ---- leading to a longer
life. Poorer people have a greater risk of premature death.
• People die younger in areas with greater income inequality
(U.S., Britain)
• Japan and Sweden have less inequality and a higher life
expectancy
• Lynch people at every income level (not just the poor) are
at a greater risk of death if they live in communities with
great income inequality.
• Some studies say that income is the key --- others say that
inequality is the key.
Optimism and Pessimism (538)
Optimistic people:
• perceive more control
• cope better with stress - ie
have smaller increases in
blood pressure and
recover more quickly from
bypass surgery
• better health --- live longer
Loosing control
• provokes an outpouring of
stress hormones
• immune responses drop
Stress and Heart (539)
• Since 1950’s coronary
heart disease is the
leading cause of death
• Behavioral and
physiological factors:
– smoking/obesity
– high-fat diets
– physical inactivity
– elevated blood
pressure and
cholesterol
Friedman Fat Wives (539)
• Friedman (1956) wives
consumed as much fat as
their executive husbands
yet the wives were less
susceptible to heart
disease ---WHY --- the
husbands had stressful
jobs - the wives didn't.
• Friedman - study of
accountants -- blood
cholesterol rises in April
and then returns to normal
after tax season
Type A Type B (539)
• Friedman and Rosenman noted the talking style/behavior
of over 3000 male interviewees
• Type A's were more reactive, competitive, hard-driving,
impatient, time-conscious, verbally aggressive and easily
angered
• Type B's were easy going, relaxed
• Type A's were more prone to heart attack - WHY - they
smoked, coffeed more, were more reactive when
challenged, secreted more hormones and had higher blood
pressure. Hormones accelerate the build up of plaque of
heart disease
• Anger, pessimism and depression all contribute to heart
problems.
Susceptibility to Disease (541)
• Historically we spoke of
psychosomatic symptoms
--- psychologically caused
physical symptoms. The
symptoms weren't real.
• Now we use the term
psychophysiological
illness -- mind-body
illness - ie hypertension
• Hypochondriasis --misinterpreting normal
physical sensations as
symptoms of disease.
Immune System (542)
• defends body by isolating
and destroying bacteria
and viruses
• includes 2 types of white
blood cell lymphocytes
• B Lymphocytes -- form in
the bone marrow -- release
antibodies that fight
bacteria infections
• T Lymphocytes -- form in
the thymus and other
lymphatic tissue - attack
cancer cells, viruses and
sometimes "good" cells
like transplants.
Macrophage (542)
Another agent of
the immune
system is the
macrophage
which identifies
and eats harmful
invaders
2 Immune System Errors (542)
1. Responds too
strongly and attacks
the body's own
tissues -- ex. arthritis
or allergies, MS,
lupus.
2. Under-responds and
allows cancer cells to
multiply
Women and Immunity (542)
• Women have
stronger immune
systems than men
so they are less
susceptible to
infections BUT
more susceptible to
self-attacking
diseases like MS
and lupus
Stress and Immunity (542)
• The brain secretes
stress hormones
(cortisol) which in
turn suppress the
immune system's
disease-fighting
lymphocytes.
• wounds heal more
slowly when we are
stressed
Fight/Flight OR Immunity (543)
•
Stress triggers fight/flight
OR immunity
• When we are diseased, our
bodies reduce muscular
energy output by
inactivity and increased
sleep.
•
If stress triggers
fight/flight the immune
system does not get the
energy and we are more
susceptible to disease.
Stress and AIDS (543)
• HIV (human immunodeficiency virus) is followed
by AIDS (acquired immune deficiency syndrome)
• HIV is a slow killer - therefore it kills more
people because they have time to spread it
• people with AIDS die of diseases like pneumonia
because they have no immune system to fight the
disease.
• Stress caused people with HIV to more quickly
develop AIDS
Stress and Cancer (543)
• Stress and negative emotion also speed up the
progression of cancer
• Rats implanted with tumor cells and exposed to
uncontrollable stress are more prone to
cancer. The stress weakens the immune system so
there is less to fight the cancer. (the stress does
not cause the cancer)
• Some studies on humans find a link between
stress and cancer and some studies don't
• Problem - people blaming themselves for getting
cancer or having "wellness macho"
Conditioning the Immune System (544)
Ader and Cohen (1985) discovered that
classical conditioning can affect the body's
immune system. On rats, they paired sweet
water with an immune-suppressing
drug. Eventually the sweet water alone
triggered the immune suppression and
tripled the likelihood of the rat getting
cancer.
Stress
• Stress, especially in
short term amounts,
motivates us ---adaptive.
• Stress, especially in
long term amounts,
depletes our immune
system and we get sick
Promoting Health (546)
Health Psychologists
• health maintenance
• coping with stress
• preventing illness
• promoting wellbeing
Coping With Stress (546)
• Stressors are unavoidable
• We must manage stress by
escaping it, confronting it
and taking steps to prevent
its reoccurrence.
• Stress management
includes aerobic exercise,
biofeedback, relaxation
and social support.
Aerobic Exercise (547)
• McCann and Holmes
(1984) - assigned
depressed subjects to
groups who did:
• 1. aerobics
• 2.
relaxation
• 3.
control group
• The aerobic group had the
greatest drop in
depression.
•
Aerobic Exercise (547)
Why???? Aerobics:
1. strengthens the heart and
lowers blood pressure
2. increases seratonin,
norepinephrine,
endorphins boosting mood
3. enhances cognitive
function
4. grows new brain cells in
mice
Biofeedback and Relaxation (548)
• Biofeedback - a system of recording, amplifying
and feeding back information about subtle
physiological responses. The machines reflect the
results of a person's own efforts so the person can
learn to control physiological responses - like a
heart rate. -- like tension in forehead muscles
(figure 14.13)
• Can we be trained to bring our heart rates and
blood pressure under conscious control?
Biofeedback (548)
• Neal Miller (1960) found that rats could modify
their heartbeat if given pleasurable brain
stimulation when their heartbeat increased or
decreased.
• Miller and Brucker (1979) - paralyzed humans
could learn to control their blood pressures.
• In 1995 research proved that biofeedback works
best on tension headaches but that other relaxation
methods work just as well
• Friedman - Type A heart attack victims - 1/2
treated normally and 1/2 treated normally plus
taught relaxation. The relaxed group had 1/2 the
repeat heart attacks.
Social Support (550)
Happily married people
live longer:
– partners encourage
doctor visits
– eat better/exercise
with prompting/ sleep
better
– drink and smoke less
– overcome stress better
– confide past traumas
rather than suppressing
them
– bolster self esteem
Social Support (550)
• Cohen (1997) - cold virus
volunteers --- those with
the most social ties were
least likely to catch a cold
and they produced the
least mucous
• Social supports also leads
to disclosure - confiding -- rather than a bottling up
of stressful issues.
Spirituality and Faith (553)
• Historically, medicine and
spirituality were
administered by the same
person.
• Later the 2 diverge.
• Now the 2 are reconverging.
• Kark (1996) - studied
religious and secular
Jewish communities. The
religious lived longer.
Spirituality and Faith (553)
• Partrige (1972) - attending
weekly church decreases
mortality rates. Potential
Intervening Variables?
Religious have
• healthier life styles
• social support
• encourages marriage
• stress protection of a religious
world view
• relaxed meditation of prayer
• HOWEVER< studies
controlling for the intervening
variables still concluded a
correlation between religion
and better health.
Complementary and Alternative
Medicine (556)
• acupuncture, massage, homeopathy,
spiritual healing, herbal, chiropractic, Qi
• Critics - alternative med is most effective
for cyclical diseases which would cure
themselves in time
• Pro - many mainstream medical practices
began as alternative med
Modifying Illness-Related
Behaviors (555)
• Smoking - stopping
smoking would increase
life expectancy more than
any other preventative
measure.
• The stats don't impress
smokers.
• Smoking correlates with
higher rates of depression,
chronic disabilities and
divorce.
When/Why People Start Smoking (558)
• usually in early
adolescence
• teens with friends who
smoke
• low-achieving teens
• rebellious and risk taking
teens
• movie models are an
influence
• parents/sibling smokers
Social-Cognitive Theory on Smoking
• We learn behaviors through
models and social rewards.
• Adolescents are self-conscious
and think everyone is
watching. So, they smoke to
imitate cool models and the
social reward of other's
acceptance.
• Tobacco companies - model
smoking through youth-oriented
themes of independence,
adventure, social approval and
sophistication.
Why Do People Not Stop Smoking (559)
•
•
•
•
3 in 4 try
nicotine is as addictive as heroine and cocaine
1 in 3 who try smoking become addicted
smokers become dependent and develop a
tolerance (need larger dose to get the same effect)
• quitting causes withdrawal symptoms of craving,
insomnia, anxiety, irritability, headaches,
constipation. A cigarette relieves your withdrawal
symptoms.
• the acute withdrawal symptoms will gradually
dissipate over 6 months.
Why Do People Not Stop Smoking (559)
Nicotine
• triggers release of epinephrine and norepinephrine
which diminish appetite and boost alertness.
• triggers central nervous system to release
neurotransmitters that calm anxiety and reduce
sensitivity to pain.
• increases release of dopamine (cocaine blocks
reuptake of dopamine)
Genes and Smoking (559)
• Cigarette addiction
---- 60% heritability
• Smokers and
nonsmokers tend to
differ in a gene that
influences
responses to
dopamine.
How Effective Are
Stop Smoking Programs? (560)
• effective in the short run
• all but 20% who quit start
again
• odds are worse if you quit
solo
• Smoking rates are down
(in America) but they are
still high among dropouts
and lower socioeconomic
levels. Smoking has
skyrocketed in Asia and in
developing countries.
How To Prevent Smoking? (561)
• McAlister (1980) - inoculate younger kids against
peer pressure to smoke - have older peers teach
younger kids to recognize and resist peer pressure
• "Chicken" ----"I'd be a real chicken if I smoked
just because you want me too!!!"
• After inoculation, McAlister found that they were
half as likely to start smoking as non-inoculated
kids (even though parents of both groups had the
same smoking rates).
How To Prevent Smoking
Non-smoking curriculum needs to contain:
1.
information about effects of smoking
2.
info about peer, parent and media influences
3.
training in refusal skills through modeling and
role playing
The other way to curb smoking is to raise the
price. Each 10% cost increase nets a 4% reduction
in smoking.
Nutrition (562)
• High-carb foods increase our tryptophan in our
bloodstream --- leading to an increase in seratonin
• High protein improves our concentration and
alertness
• High Blood Pressure ---- diet high in salt and low
in calcium
• Breakfast ---- makes us less fatigued by late
morning
• Depression --- diet low in omega 3 (good fat)
Obesity and Weight Control (563)
• 65% of the U.S. is overweight
• fat = stored energy used by the body when food is
scarce = adaptive in times of feast and famine =
maladaptive in today's world of plentiful food
• Obesity --- increases diabetes, high blood
pressure, heart disease, gallstones, arthritis, cancer
• worse for "apples" than for "pears"
• physical and psychological threat - how you feel
and how others treat you --- (the same actor
wearing 30 more pounds is less likely to get the
job)
Physiology of Obesity (565)
•
•
•
•
BMI = Body Mass Index
should be under 26
obese is a score of 30 or more
BMI = kg weight
squared height in metres
• (inches/39.4) = metre (x metre)
• 1 pound of fat = 3500 calories
• Dieters have been told they will loose a pound for
every 3500 calories reduced in their diet. This is
FALSE because of the physiology of fat.
Physiology of Obesity
• Why??????????????????
• Fat Cells - adults have about 30 billion fat cells
• a fat cell can be empty or inflated. When inflated it can
swell 2 or 3 times a normal size and then it divides. Once
the number of fat cells increases (through genetics, early
child eating, adult eating) it never decreases. Fat cells can
shrink but they never disappear.
• Our bodies maintain our fat - fat tissue has a low
metabolic rate therefore it takes less energy to maintain a
fat cell. Thus, once we become fat we require less food to
maintain our weight then we did to attain our weight.
Set Points and Metabolism (565)
• Obese people have higher set points - weight thermostats
set to maintain body weight within a range.
• when their body weight drops below the set point, their
hunger increases and their metabolism decreases.
• Therefore, after the rapid weight loss of the first 2 or 3
weeks of a diet, any further weight comes off more
slowly. The metabolic rate drops as you lower your food
intake --- the body adapts to starvation by burning fewer
calories.
• Therefore, reducing your food by 3500 calories my not
reduce your weight by one pound!!!!! And, after a diet,
the body is still in conservation mode so the old amount of
food that used to maintain your weight may now actually
increase your weight.
The Genetic Factor (566)
• Adoptee studies - despite the same food the adoptee's
weight is like their biological parents
• Identical twins reared apart have similar weights.
• Genes
– influence when our intestines signal "full"
– influence how efficiently we burn calories or convert
extra calories to fat
– influence how "still" or "fidgety" we are
• Genes determine why one person is heavier than another
but the environment determines why people are heavier
today than they were 50 years ago
• 5 MCDONALD'S FRIES = ONE SERVING!!!!!!!!!!!!!
Losing Weight (568 - 573)
• most who loose weight
eventually gain it back
• better results with
programs that modify lifestyle and ongoing eating
habits
• women and even more so
girls try loosing weight
• sustained exercise is the
best possibility