class 2 Flashcards
Stress is
a process involving perception, interpretation, response and adaptation to harmful, threatening, or challenging events
Perception of stress:
arises from events that cause stress
Stressors (e.g. excessive noise, pain)
Life events (e.g. new job, moving house, exams)
Interpretation of stress:
Cognitive and affective processes that
evaluate the stress, and the available coping mechanisms
this is a process of appraisal
Response to stress:
Biological responses and adaptations needed to cope with the stressor
Systems: GI, CNS, musculoskeletal, cardiovascular, endocrine, respiratory, other
Acute and chronic responses
Adaptation to stress:
Behavioral and cognitive response to the stressful event
Coping
e.g. changes in sleep patterns, eating habits, thought processes, changing priorities, etc.
So what
definition of stress was coined by Hans Selye, a Canadian endocrinologist
“the body’s non-specific response to any demand made upon it. It is not a disease but can contribute to ill health.” This definition refers to the body’s need to maintain homeostasis at all times.
positive aspects of stress.
Positive stress includes the normal physiological activity needed to maintain homeostasis, and the healthy emotional stress that makes life interesting & exciting. He calls this EUSTRESS.
negative aspects of stress.
Negative stress indicates the harmful effects of physical & emotional stress. An overload of stress from a situation of under or over arousal going on for too long produces first unpleasant feelings, and then physical damage and fatigue and ultimately even death. He calls this DYSTRESS.
Selye’s distinction is a valuable one. It recognizes the
inevitability and desirability of having some stress in your life while guarding against its ill effects. Manageable levels of stress, for reasonable duration, mobilize your resources and get you going on tackling the tasks and problems in your life.
STRESSOR:
potential triggers to the stress response (fight or flight); can be environmental agents/events, within or outside the body eg: physical effort, heat, cold, hunger, fatigue, pain, threats to self-esteem
STRESS REACTIVITY:
the body’s physiological response to the stressor; very individual; responses may be uncontrolled or excessive, not appropriate, or necessary to the trigger
duration of a stressor
a brief, acute event that does not recur:
the body’s response is rapid & efficient eg: jumping out of the way of an oncoming car
duration of a stressor
a series of stressful events that occurs as a result of an initiating event:
repeated stressful events which increase physiological responses; response may escalate over time; eg: job loss, can’t pay rent, car is repossessed, etc
duration of a stressor
chronic intermittent stress:
requires frequent responses to a regularly occurring stressor; eg: school exams, work deadlines
duration of a stressor
chronic & sustained stress:
continued exposure to stress depletes the body’s resources, allowing illness to take hold; eg: single parent trying to balance work, children, finances, etc
General Adaptation Syndrome (GAS)refers to
the 3 stages the body goes through, according to the DURATION of the stressor.
GAS stage 1: ALARM:
the first exposure to a particular stressor; cortisol levels are high
GAS stage 2: RESISTANCE/ADAPTATION:
if stress continues, the body tries to resist the stress & adapt to it; cortisol levels decrease as the initial alarm diminishes; the duration of this phase depends on the intensity of the stressor and the body’s ability to adapt; the ability to adapt will be decreased by lack of sleep, poor diet, working long hours
GAS stage 3: EXHAUSTION:
after long exposure to the stressor, the body’s adaptive energy is exhausted; signs of acute stress (the alarm phase) reappear
autonomic nervous system regulates the internal functions of the body and maintains homeostasis. It has 2 parts -
the parasympathetic system (rest and digest or feed and breed) and the sympathetic system (fight or flight).
Stimulation of the parasympathetic system results in:
reduced heart rate
constriction of pupils
stimulation of salivary & gastric glands
stimulation of peristalsis in the gut
stimulates urination by contracting bladder & relaxing urethral sphincter
Stimulation of the sympathetic system results in:
mental alertness to deal with danger
increased cellular metabolism
release of glucose from fat & liver for a burst of energy
increased heart rate, increased force of heart contractions
vasoconstriction in skin and abdomen to limit bleeding in case of injury
increased blood pressure due to vasoconstriction (above)
dilation of bronchioles to increase oxygen intake
dilation of pupils to increase visual acuity
inhibition of salivary & gastric glands (not essential if life is in danger)
Short term sympathetic stimulation is normal & is needed to deal with daily stressors. However, if the stressor is very intense, or if the stress lasts for long periods, sympathetic stimulation can lead to other health problems:
too much glucose can lead to diabetes
high heart rate & blood pressure can lead to heart attack
inhibited GI system leads to irritable bowel, constipation
The human body has a remarkable system to help us function when we are “under stress”. This is called the Stress Axis, or the
hypothalamic-pituitary-adrenal axis, and it was first described by Hans Selye.
The “first stop” along the stress axis and site of CRH synthesis in response to stress. This region of vertebrate brain is involved in regulation of neural and hormonal functions.
Hypothalamus
a peptide synthesized and secreted by the hypothalamus in the early stages of the stress response along the stress axis.
CRH, Abbreviation for corticotrophin releasing hormone,
A gland located just below the brain, adjacent to the hypothalamus. When CRH reaches the pituitary, this gland synthesizes and secretes a hormone, ACTH.
Pituitary Gland
a peptide from the pituitary that carries the “stress response” message to the adrenal glands.
ACTH
Abbreviation for adrenocorticotrophin hormone,
In response to ACTH, the ———- synthesize and secrete the stress hormone, cortisol, into the blood.
Adrenal Glands
A pair of glands found atop the kidneys.
The stress hormone in humans. This steroid-type hormone can influence the operation of many physiological systems.
Cortisol
Stress Axis Basics - a Feedback Loop
- A physiological stress or psychological trauma hits. The hypothalamus receives input from elsewhere in the brain and other organ systems. It responds by secreting CRH.
- CRH travels to the nearby pituitary gland. The pituitary gland then secretes a hormone, ACTH, into the bloodstream.
- ACTH reaches the adrenal glands, located on top of each kidney. In response, the adrenal glands release the “stress hormone”, cortisol.
- Cortisol acts on many systems to adjust the body physiology, helping it to cope with the stress. And, since too much cortisol causes problems, this hormone completes the loop by signaling the hypothalamus and pituitary to “turn off” the stress response.
Glucose metabolism;
Cortisol promotes gluconeogenesis, a process that causes amino acids (breakdown products of protein) to be converted into glucose. At the same time, it reduces the utilization of glucose by the cells. Both these effects increase the blood glucose levels
Protein metabolism:
Cortisol decreases protein stores in the cells by reducing protein synthesis within the cells and promoting protein breakdown. This causes protein depletion in most tissues. However, the liver cells are stimulated to produce more protein and this also increases the blood proteins. At the same time, the protein that is “recalled” is ultimately used for gluconeogenesis as explained above under carbohydrate metabolism
Immune function & inflammatory response:
Cortisol can block the various stages of inflammation thereby stopping the inflammatory process or even preventing it from starting up. Therefore, it is a natural anti-inflammatory in the body. Cortisol also reduces the concentration of certain white blood cells like eosinophils and lymphocytes which may also reduce inflammation but at the same time, the immunity is partly compromised.
- A physiological stress or psychological trauma hits. The hypothalamus receives input from elsewhere in the brain and other organ systems. It responds by secreting CRH.
- CRH travels to the nearby pituitary gland. The pituitary gland then secretes a hormone, ACTH, into the bloodstream.
- ACTH reaches the adrenal glands, located on top of each kidney. In response, the adrenal glands release the “stress hormone”, cortisol.
- Cortisol acts on many systems to adjust the body physiology, helping it to cope with the stress. And, since too much cortisol causes problems, this hormone completes the loop by signaling the hypothalamus and pituitary to “turn off” the stress response.
Other important Cortisol functions:
BP regulation
Insulin release for blood sugar maintenance
a SMALL amount of cortisol is okay…
quick burst of energy for survival reasons
heightened memory function
decrease in pain sensitivity
helps maintain homeostasis
too much cortisol is bad…
impaired cognitive function decreased thyroid function blood sugar imbalance - hyperglycemia decreased bone density decreased muscle tissue increased BP lowered immunity & inflammatory responses; slow wound healing, increased risk of infection increased abdominal fat heart attack, stroke, metabolic disorder
Anxiety Disorder presents as
a chronic generalized sense of uneasiness & fear. Often, there is no clear cause for the emotions. People with anxiety disorder often have chronic fatigue & headaches. Phobic behavior may also be present, such as fear of heights, flying, or creatures
Panic Attacks are much more
abrupt & intense. Along with severe anxiety, there is a feeling of impending disaster or death. Other symptoms may include heart palpitations, shortness of breath, hot flashes, GI disturbances, insomnia. Those who suffer from panic attacks seem to be more sensitive to lactic acid imbalances. When there is too much lactic acid, the body triggers hyperventilation, to remove the excess CO2 from the blood stream. This hyperventilation can trigger a panic attack
Hyperventilation, or over-breathing, is a widespread disorder closely connected to panic attacks and phobic behavior. It is commonly found in those undergoing stress related to marriage, work, or finances. It results in
a rapid reduction of blood carbon dioxide, which causes:
Increased blood alkalinity (homeostasis)
Increased nociceptor activity (hypersensitivity)
Anxiety
Most cases of hyperventilation exist due to a learned pattern of breathing in response to a real or assumed stressful situation. If this response occurs inappropriately (when even small, daily stressors trigger it) it can lead to
imbalanced blood gas levels, changes in blood alkalinity/acidity, and a host of other symptoms:
Erratic heartbeats and/or chest pain
Breathless “attacks” at rest for no reason
Frequent sighing and/or yawning (average is once every 5-10 minutes)
Irritable coughing and chest tightness
Dizziness and “spaced out” feelings
“pins and needles” or numbness in lips, fingertips and toes
Gut disturbances – indigestion, nausea, wind or irritable bowel
Muscles aches, pains, or tremors
Tiredness, weakness, disturbed sleep, and nightmares
Phobias
Clammy hands, flushed face, feelings of high anxiety
Sexual problems
Normal, easy breathing:
12 regular breaths/minute (10-14 acceptable)
70-80% of the work of respiration is done by the diaphragm
Accessory muscles of respiration are used during or shortly after extreme effort or stress
Inspiration: 2-3 seconds
Expiration: 3-4 seconds
Little or no upper chest movement
Nose breathing
chronic hyperventilators:
18 or more breaths per minute work is being done by accessory muscle of respiration very little work done by the diaphragm inspiration is longer than expiration mouth breathing
Physiological changes related to Hyperventilation
Short term changes:
Adrenalin pours into the bloodstream Heart and breathing rates speed up Muscles become tense Eyesight and hearing sharpen The pain threshold drops and pain is less intense
Physiological changes related to Hyperventilation
Chronic changes:
More carbon dioxide is breathed out; carbon dioxide levels in the blood start to drop
Normal pH becomes more alkaline = respiratory alkalosis
Smooth muscle cells are galvanized into action by lowered carbon dioxide levels, which leads to tightening or constriction of the blood vessels
The heart and pulses start pounding; the hyperventilator may feel panic stricken, with palpitations and chest pain
The brain may have its oxygen supply cut by as much as 50%
Habitual mouth breathers develop irritable upper airways, with the risk of repeated throat infections
A very common sign of hyperventilation is repeated throat clearing – the AAHHRRRRMMMMM bug
Triggers increased histamine levels in the blood – sweaty palms and armpits, clammy skin, flushed face are all signs of this
People with allergies such as hayfever, skin rashes, food intolerances, or asthma find their symptoms much worse
Response to pain is amplified – stiffness in muscles and joints feels rheumatoid-type pain
Heart disease-type symptoms, like tight chest pain or pounding pulses
Mental fuzziness, headaches, or loss of concentration can erode self-confidence, especially if work suffers
Making love can be a nightmare – for both partners – if the “heavy breathing” that precedes orgasm leads to a panic attack
Vivid dreams, nightmares, and disturbed sleep patterns commonly accompany hyperventilation – creates distress 24/7
Treating Hyperventilation
Becoming aware of faulty breathing problems
Learning to nose-diaphragm breathe
Suppressing upper-chest movement during normal breathing
Reducing breathing to a slow, even, rhythmic rate
LUNG HO Salute
Place your dominant hand on your abdomen, between the lower ribs and umbilicus
Other hand on the sternum; just below the clavicles
Take a deep breath
Notice which part of your chest moved first? Which part moved the most? Did you breathe through your nose or your mouth?
If you breathed in through your nose, and your abdomen expanded first, and you felt almost no upper-chest movement, then you are a good breather.
If you breathed in fast through your mouth, and your upper chest heaved first, and you felt little or no movement (or your abdomen drew INWARD), then you are a weak breather. You can change this through breath training.
Pranayama
Pranayama is a traditional practice of yoga breathing. A very simple form of it has been found to be useful in retraining hyperventilators to use a more appropriate pattern of breathing, especially in stressful situations. It calls for an ideal ratio of inhalation to exhalation of 1:4
The focus is for the exhalation to take appreciably longer than the inhalation, and breath must be through the nose
