Stress and Coping

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Stress and Coping
Josée L. Jarry, Ph.D., C.Psych.
Health Psychology, psy333
Department of Psychology
University of Toronto
October 28, 2002
Definition (1)
Aldwin (1994)
• Quality of experience, produced through a personenvironment transaction, that through over- or under-arousal,
results in psychological or physiological distress
Hans Selye
• The non-specific result of any demand upon the body, be the
effect mental or somatic
• Eustress is a positive stressful experience, a state of physical
and psychological well-being that is associated with increased
motivation and the acceptance of a challenge.
• What is essential to well-being is a balance to produce an
optimal level of arousal
• Too little stress can be as harmful as too much
• Stress can result from being over- or under-stimulated
Definition (2)
Lazarus & Folkman (1984)
• A relationship between a person and the environment that
is appraised by the person as taxing or exceeding his or
her resources and endangering his/her well-being
• This definition introduces the important notion of
subjective appraisal
Walter Canon
• Introduced the concept of homeostasis: body’s attempt at
maintaining a stable internal state
• Stress challenges homeostasis
Fight or Flight response
• Complex ANS reaction in preparation for emergencies
Definition (3)
Rice, P. R. (1999)
Stressors
• External, environmental demands placed on us that cause
us to feel stressed
Subjective response
• Interpretive mental state of the individual
• Allows one to diminish, augment, or distort the impact of
external events
Body’s physical response to stress
• Physiological challenges which, if prolonged, can result in
a negative state, or alternatively, an improved capacity to
cope physiologically
The Physiology of Stress
• 2 major components to the physical
response to stress:
• Nervous system
• Endocrine system
Structure of the Nervous System
Central nervous system is made of:
• Brain
• Spinal cord
Peripheral nervous system is made of:
Somatic nervous system
• Receives information from the sensory organs
• Controls movements of the skeletal muscles
Autonomic nervous system (ANS)
• Primarily serves internal organs
Has 2 divisions:
• Sympathetic
• Parasympathetic
Sympathetic Response to Stress
Hypothalamus causes:
Increases arousal in the sympathetic nervous system
• Increased heart rate & blood pressure
• Constriction of peripheral blood vessels
• Respiration rates increase
• Bronchial tubes dilate
• Pupils dilate
• Digestive processes decrease
Sympathetic activation prepares the body for intense
motor activity
Parasympathetic response to stress
Serves regenerative, growth-promoting, energyconserving functions
Its effects include the opposite of the effect of the
sympathetic nervous system
Functions under normal, non-stressful conditions
Also activated by the hypothalamus
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re-establishes homeostasis in the system
reconstructive process following stressful experience
slows the heart rate & decreases blood pressure
decreases muscle tension
slows respiration
neutralizes fight or flight response
Structure of the Endocrine System
• The endocrine system consists of ductless glands
distributed throughout the body
• The neuroendocrine system is made of those
endocrine glands that are controlled by the
nervous system
• Glands of the endocrine and neuroendocrine
systems secrete chemicals called hormones
• Hormones move into the blood stream to be
carried throughout the body
• Specialized receptors on target tissues or organs
allow hormones to have specific effects even
though they circulate throughout the body
Endocrine Responses to Stress
Hypothalamus causes:
• The pituitary gland to secrete adrenocorticotropic
hormone (ACTH) that stimulates the adrenal cortex
• Sympathetic fibers to directly activate the adrenal
medulla
• The adrenal glands are located on top of each kidney
• Each gland is composed of:
– an outer covering: the adrenal cortex
– an inner part: the adrenal medulla
• Both secrete hormones that are important in the
stress response
Adrenomedullary Response - SAM
Occurs through the activation of the sympatheticadrenal medulla (SAM) complex:
• Perception of stress causes the hypothalamus (via
nervous connection) to activate sympathetic fibers
• Sympathetic fibers activate the adrenal medulla
• Adrenal medulla secretes the catecholamines:
epinephrine & norepinephrine
This causes:
• Increased heart rate, blood pressure, breathing rate &
blood glucose levels
• Shuts down digestive system
• Rapid, short-lived response to stress
Adrenocortical Response - HPA
Occurs through the activation of the hypothalamuspituitary-adrenal (HPA) cortex complex:
• Perception of stress causes the hypothalamus to
release ACTH releasing hormone
• This causes the anterior pituitary to secrete ACTH
• ACTH stimulates the adrenal cortex to secrete
glucocorticoids and mineralocorticoids
Glucocorticoids
• Protein and fat get metabolized into glucose
• Reduce inflammation, suppress immune cells
Mineralocorticoids
• Blood volume and pressure increase
Sympathetic and Endocrine Responses to Stress
• Stress perception causes a chain reaction:
SAM
• rapid, short-term stress reaction
• the sympathetic NS stimulates the adrenal medulla
• the adrenal medulla produces epinephrine and
norepinephrine
HPA
• slower but longer-lasting response
• the pituitary releases ACTH
• ACTH causes the adrenal cortex to release
glucocorticoids and mineralocorticoids
Brain Response to Stress
Limbic System
• Adds an element of emotion to the experience of
stress
• Usually negative emotions: fear, anger, anxiety, pain
Reticular formation
• Communication network that filters messages to the
body
• Receives input from all the sensory systems and
determines which sensory information is processed or
blocked
• This allows us to selectively attend to specific tasks
while ignoring irrelevant information
The General Adaptation Syndrome (1)
Defined by Selye in 1956. Comprises 3 stages:
Stage I: Alarm
• The body’s defences against stressors are mobilized
through activation of the sympathetic nervous
system
• Activation of the SAM complex
• Arousal of the sympathetic nervous system releases
hormones (adrenaline) that help prepare the body to
meet stress and danger
• Highly adaptive short term response to an
emergency situation
The General Adaptation Syndrome (2)
Stage II: Resistance
• The body enters this stage if the stress is prolonged
• Activation of the HPA complex
• Arousal is lower
• But the body continues to draw on internal resources
at an above normal rate
• Outwards appearance seems normal
• Physiologically, the body’s internal functioning is
not normal
• Sets the stage for diseases of adaptation (e.g., peptic
ulcers, ulcerative colitis)
The General Adaptation Syndrome (3)
Stage III: Exhaustion
• Continued exposure to the same stressor
drains the body further
• The capacity to resist is depleted
• Illness results
• This stage is characterized by activation of
the parasympathetic division of the ANS
• But at an abnormally low level
• In severe cases, results in death
Cognitive - Transactional Model
Lazarus & Folkman (1984)
• Propose that the interpretation of stressful events
is more important than the events themselves
• It is neither the environmental event nor the
person’s response that defines stress
• It is the individual’s perception of the
psychological situation that defines stress
• Stress is a function of the person’s feeling of
threat, vulnerability, and ability to cope rather than
a function of the stressor
• Distinguish three kinds of appraisal
Primary appraisal
• Initial evaluation of a situation
3 possible outcomes:
Irrelevant
• the event has no implication for the individual’s
well-being
Benign-positive
• the event may increase well-being
Stressful
• the situation is perceived as harmful, threatening,
or challenging
Primary appraisal (2)
Harm/loss
• involves actual significant physical or psychological
loss
• psychological damage that has already been done
Threat
• the anticipation of harm or loss
• allows to anticipate and prepare for the future
Challenge
• the event is perceived as stressful
• the focus is on positive excitement
• refers to the person’s confidence in overcoming
difficult demands
Secondary Appraisal
Concerned with a person’s evaluation of his/her ability to
cope with the situation
The individual asks 3 questions:
• which coping options are available?
• the likelihood that one can apply the strategy
• the likelihood that any given options will work: will it
reduce stress?
Reappraisal
• continuous reappraisal on the basis of new information
• identical to the initial process
• may lead to more stress
Coping (1)
Lazarus and Folkman (1984)
• Constantly changing cognitive and behavioural efforts to
manage specific internal and/or external demands that are
appraised as taxing or exceeding the resources of the
person
Several important elements of the definition:
• Coping is a process of constant evaluation of the success
of one’s strategies
• Coping is learned as one encounters situations
• Coping requires effort
• Coping is an effort to manage. Success is not contingent
on mastery, just good enough
Coping (2)
Health & energy
Positive belief
• the ability to cope is enhanced when people believe they
can successfully bring about desired consequences
Problem-solving skills
• having specific knowledge or abilities related to specific
problem
Social skill
• ability to get other people to cooperate
Social support
• feeling of being accepted, loved, or prized by others
Material Resources
Coping (3)
Problem Focussed Coping
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consists of changing the situation
redefining the problem
looking at alternative solutions
evaluating the implications of the alternatives
choosing the best one to act on
Emotion-focussed coping
• consists of controlling and possibly changing the emotional
response to an event
• cognitive responses such as avoidance or minimization
• the goal is to decrease emotional distress
• often used when the individual feels that nothing can be done
about the situation
Stress and Control
Stephen Weiss (1968, 1971)
Study 1
• reliable escape response reduces development of ulcers
Study 2
• predictable stressors produced fewer ulcers
• true even in the absence of an escape response option
Study 3
• feedback about effectiveness of response results in fewer ulcers
Conclusion
• the physiological effects of stress can be greatly reduced if the
organism can engage in controlling behaviour
• getting feedback that one’s behaviour is effective can further
reduce the physiological effects of stress
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