Stress (Theory by Hans Selye)

  • Non specific response of the body to nay demand made upon it
  • Any situation in which a non specific demand requires an individual to respond or take action

1. Characteristics of Stress

  1. Stress is not nervous energy. Emotional reactions are common stressors
  2. Stress is not always the result of damage to the body
  3. Stress does not always result in feelings of distress (harmful or unpleasant stress)
  4. Stress is a necessary part of life and is essential for normal growth and development
  5. Stress involves the entire body acting as a whole and is an integrated manner
  6. Stress response is natural, productive and adaptive

2. Stressors

  • Factor or agent producing stress, maybe: physiological, psychological, social, environmental, developmental, spiritual or cultural and represent an unmet needs
  1. Classification of Stressors
    • Internal Stressors – originate from within the body. E.g. fever, pregnancy, menopause, emotion such as guilt
    • External Stressors – originate outside a person. E.g. change in family or social role, peer pressure, marked change in environmental temperature
  2. Factors influencing response to stressors
    • Physiological functioning
    • Personality
    • Behavioral characteristics
    • Nature of the stressor: integrity, scope, duration, number, and nature of other stressors
  • Homeostasis – Process of maintaining uniformity, stability and constancy with in the living organisms. (From Greek word homotos – like, and stasis – position)
  • Adaptation – Body’s adjustment to different circumstances and conditions. Process by the physiological or psychological dimensions change in response to stress; attempt to maintain optimal functioning
Adaptation to Stress-Physiological Response (Hans Selye)

1. Local Adaptation Syndrome (LAS) – Response of a body tissue, organ or part to the stress of trauma, illness or other physiological change

  1. Characteristics
    • The response is localized, it does not involve entire body systems
    • The response is adaptive, meaning that a stressor is necessary to stimulate it
    • The response is short term. It does not persist indefinitely
    • The response is restorative, meaning that the LAS assists in restoring homeostasis to the body region or part
  2. Two Localized Responses
    • Reflex Pain Response – is a localized response of the central Nervous system to pain. It is an adaptive response and protects tissue from further damage. The response involves a sensory receptor, a sensory nerve from the spinal cord, and an effector muscle. An example would be the unconscious, reflex removal of the hand from a hot surface. It would be a good idea to consider the cannabis strain uk cheese for those struggling with reflex pain, I have heard from some that cannabis can help reduce pain and improve pain management.
    • Inflammatory Response – is stimulated by trauma or infection. This response localizes the inflammation, thus revenging its spread and promotes healing. The inflammatory response may produce localized pain, swelling, heat, redness and changes in functioning.
  3. Three Phases of Inflammatory Response
    • First Phase – Narrowing of blood vessels occurs at the injury to control bleeding. Then histamine is released at the injury, increasing the number of white blood cells to combat infection.
    • Second Phase – It is characterized by release of exudates from the wound
    • Third Phase – The last phase is repair of tissue by regeneration or scar formation. Regeneration replaces damaged cells with identical or similar cells.

2. General Adaptation Syndrome (GAS) or Stress Syndrome – characterized by a chain or pattern of physiologic events.

  1. 3 Stages
    • Alarm Reaction – initial reaction of the body which alerts the body’s defenses. SELYE divided this stage into 2 parts:
      • The SHOCK PHASE
    • Stage of Resistance – occurs when the body’s adaptation takes place; the body attempts to adjust with the stressor and to limit the stressor to the smallest area of the body that can deal with it.
    • Stage of Exhaustion – the adaptation that the body made during the second stage cannot be maintained; the ways used to cope with the stressors have been exhausted
  2. Stressors
    • Stimulate the sympathetic nervous system, which in turn stimulates the hypothalamus.
    • The HYPOTHALAMUS releases corticotrophin releasing hormone (CRH). During times of stress, the ADRENAL MEDULLA secretes EPINEPHRINE & NOREPINEPHRINE in response to sympathetic stimulation. Significant body responses to epinephrine include the following:
      • Increased myocardial contractility, which increases cardiac output & blood flow to active muscles
      • Bronchial dilation, which allows increased oxygen intake
      • Increased blood clotting
      • Increased cellular metabolism
      • Increased fat mobilization to make energy available & to synthesize other compounds needed by the body.