This is the Chapter 16 of the book Introduction to Health Psychology (Val Morrison_ Paul Bennett) 4th Edition. Which is content for the exam of the component Health Psychology of Module 5 (Health Psychology & Applied Technology) of the University of Twente, in the Netherlands.

Ch.16: Pain

Functional, unpleasant, and it warns us of potential damage to the body. Reflex action, pull away from its cause or to try and reduce it in some way. May also signal onset of disease

• Congenital universal insensitivity to pain (CUIP): die at a young age because they fail to respond to illnesses of which the main symptom is pain or to avoid situations that risk
• Phantom limb pain: feel pain in non-existent limb, sometimes for many years

Types of pain:

• Acute pain: lasting 3-6 six months, involving some form injury, generally pain disappears once the damaged tissue has healed. However, acute pain may be recurrent -->
  • Migraine (headache associated with changes vascular flow within the brain, with symptoms --> nausea/vomiting/sensitivity to light), headaches or trigeminal neuralgia (inflammation trigeminal nerve that causes sharp and severe facial pain)
• Chronic pain: Lasts more than 6 months. Begins with episode of acute pain that fails to improve over time.
  
  • Pain with an identifiable cause
  • Pain with no identifiable cause

1. Chronic benign pain: pain is experienced to a similar degree over time
2. Chronic progressive pain: pain progressively worse over time

• Nature of Pain:

1. Type of pain: sharp and hot -->  stabbing, shooting
2. Severity of pain: from mild discomfort to excruciating
3. Pattern of pain: brief, continuous and intermittent.

Living with pain:

• Organise day around pain --> prevented from engaging in physical, social and even work activities
  • Physically demanding jobs most likely to lose them as a consequence of any physical limitations caused by pain
  • Reciprocal relationship: depression --> high levels reporting of pain symptoms. In other cases, strain living with pain and the restrictions on life --> depression
• Bokan et al. (1981) ‘gain’ or reward associated with pain:
  
  • Primary (intrapersonal) gain: expressions of pain results in the cessation or reduction of an aversive consequence (e.g. household chore)
  • Secondary (interpersonal) gain: pain behaviour results in a positive outcome (e.g. expressions of sympathy or care)
  • Tertiary gain: pleasure associated with helping an individual with pain
• Brena and Chapman (1983) ‘five Ds’: increasing inactivity

1. Dramatization of complaints
2. Disuse through inactivity
3. Drug misuse in response to pain behaviour
4. Dependency learned helplessness and impaired use of personal coping skills
5. Disability due to inactivity

• Good social support: less pain and better physical functioning
  • Encouraged by friends to take part in activities/more positive coping strategies

Biological models of pain:

• Specificity theory: ‘pain receptors’ when activated transmit information to centre in the brain, which processes pain-related information --> produces the sensory experience of pain
  • Von Frey: added to this theory by suggesting that our skin includes three different types of nerve, each of which responds to touch, warmth or pain
  • Goldscheider: pain sensations occurred only when the degree of nerve stimulation crossed a certain threshold

Challenge simple biological theories of pain:

• Pain in the absence of pain receptors
  • ‘phantom limb pain’
• ‘Pain receptors’ that do not transmit pain
  
  • CUIP, experience painless bone fractures
• Psychological factors on the experience of pain.
  
  • Mood: anxiety and depression reduce pain tolerance
    
    • Influences the perception of pain – and pain influences mood
  • Attention: focusing on pain increases the experience of pain.
    
    • Evidence fewer people experience pain following physical trauma at times of intense stress, such as being on the battlefield
    • Cold pressor test: either concentrate on computer-based task or on pain sensations --> those focused on the pain least able to tolerate it
    • Attentional bias: respond to acute pain with a degree of fear, worry --> begin to check for pain sensations --> pains pass unnoticed in others, they are now labelled as symptomatic of an underlying problem.
      
      • Van Damme et al.’s (2010) motivational account of bias towards pain-related stimuli: evolutionary bias towards automatically attending to pain, individual may consciously elect to prioritise attempts at pain above other goals
        
        • chronic pain resulting in the long-term interruption of attention towards other goals.
      • Eccleston and Crombez (1999): three basic responses to pain

1. Escape behaviours
2. Pain demands and captures attention
3. Ability of pain to capture attention, influenced by a number of characteristics of the pain -->  intensity, novelty, ….
   
   • Cognitions: expectations of increases or reductions in pain can be self-fulfilling.
     
     • Individuals high control beliefs may experience less pain
     • The nocebo response: negative expectations can lead to increases in pain
   • Social context: the influence of others around us.
     
     • Socio-communication in pain, Hadjistavropoulos et al. (2011): expression of pain, but also its experience, can be modified by the presence of others.
       
       • Males are likely to report less pain in the presence of an attractive female
       • Verbal reporting: ability to both express and understand pain --> evolutionary benefit

Psychobiological theory of pain:

• Processes involved experience of pain:
  • Sensory information from the site of the painful stimulation
  • Emotional and cognitive processes
• Gate control theory of pain (Melzack and Wall, 1965): degree pain experienced derived 2 set of processes:

1. Pain receptors transmit information to a series of ‘gates’ in the spinal column. Nerves link to other nerves along the spinal column that transmit information up to pain centres in the brain.
2. As experiencing physical damage, we also experience related cognitions and emotions, results in the activation of nerve fibres taking information brain down the spinal column to the gate at incoming pain signals
   • • Anxious thoughts  ‘open’ the gate and increase our experience of pain
     • Reticulospinal fibres: neural activity are transmitted down the spinal column through these fibres

• Transmission info through nerves known as nociceptors:
  • A delta fibres (types I and II):
    • Respond to light touch, mechanical and thermal stimuli; carry information about brief sharp pain
  • C polymodal fibres:
    
    • Dull, throbbing, pain
    • Experienced for a longer period than that from the A delta fibres.
• Response to injury:
  
  • Mediated by A delta fibres -->  experience of sharp pain.
  • Followed by a more chronic throbbing pain mediated by the C polymodal fibres
• Substantia gelatinosa: A and C fibres transmit information to these areas in the spinal cord
  
  • Information from A fibres is taken to the thalamus --> to the cortex --> initiate action to remove them from the source of the pain.
  • C fibres follows a pathway to the limbic system, hypothalamus and autonomic nervous system --> allows us to respond quickly to remove ourselves from harm.

  • Thalamus: links basic functions of the hindbrain and midbrain with the higher centres of processing --> the cerebral cortex. Regulates attention and contributes to memory functions portion that enters the limbic system --> involved in emotions. Limbic system: role in coordinating emotions. It links sensory information to emotionally relevant behaviour Hypothalamus: regulates appetite, sexual arousal and thirst. Some control over emotions

• Factors influence realsease endorphins:
  • Focusing on the pain: reduces the amount of endorphins released and opens the gate.
  • Emotional and cognitive factors: feeling optimistic and unconcerned --> increases endorphin release and closes the gate
  • Physical factors: relaxation increases endorphin release and lessens the experience of pain.

Neuromatrix:

Network of neurons linking the thalamus, cortex and limbic system in the brain.

• Melzack (2005) model: 3 key assumptions

1. neural processes that are involved in pain in the intact body --> also involved in pain perception in the phantom limb.
2. Pain can be felt in the absence of inputs from the body
3. Body is perceived as a unity, distinct from surrounding world

• Neurosignatures:

1. The body-self matrix: processes and integrates incoming sensory and emotional information
2. The action neuromatrix: develops behavioural responses in response to these networks

• ‘Sentient neural hub’: consciously aware of pain after this integrated network of information --> stream of nerve impulses is converted into a continually changing stream of awareness.
• Phantom limb pain (Melzack’s theory): limbs removed, body still sends signals to try to move them --> when they do not move --> stronger and more frequent messages may be sent to the muscles --> perceived as pain

Cope with pain:

Measuring pain:

• Numerical rating scales: frequently used, patients difficult to consider pain in numerical terms
  • However, it simply measures sensation of pain, and pain is multidimensional
• McGill pain questionnaire 1975: provides a multidimensional understanding of the nature of the pain
  
  • Type of pain: scale from ‘none’ to ‘severe’
  • Emotional response to the pain: tiring, fearful, …
  • Intensity of the pain: ‘no pain’ to ‘worst possible pain’
  • Timing of pain: brief, continuous or intermittent.
• Responses to pain:
  
  • Verbal/vocalisations: complains
  • Motor behaviour: laboured movement, seek help/pain reducing behaviour
  • Treatment behaviours: taking medication
  • Functional limitations: reduced activity

Increasing control:

• Patient-controlled analgesia (PCA): patient controls how much analgesic drug they receive with some controls built into delivery system so they cannot exceed a specified dosage
  • Patients can control the timing of their pain relief --> less anxious --> use less analgesic

Teaching coping skills:

• Relaxation:
  • May act as a form of distraction
  • Promotes endorphin release --> direct impact on pain experience

Hypnosis:

Patient experience changes in sensations, perceptions, thoughts or behaviour

• Reliable and significant effect on acute pain
• Also aid patients’ physical recovery

Chronic pain:

• Transcutaneous electrical nerve stimulation (TENS): small electrical device, method of pain control
  • Electrical stimulation of A beta fibres, to compete with the pain signals of pain-related nerves
  • Stimulate C fibres to result in endorphin release.
• Biofeedback techniques: using monitoring devices to provide information regarding an autonomic bodily function --> attempt to gain some voluntary control over that function.
  
  • Electromyographic (EMG) biofeedback: measures amount of electrical current in the muscles --> higher voltage = higher tension
    
    • Most direct and accurate form of feedback
  • Galvanic skin response (GSR): general tension in the body by measuring subtle changes in the moisture (sweat)
    
    • Increased sweat --> increased general muscle tension
  • Thermal biofeedback: based on a theory that warming the skin can reduce the pain of headaches. Temperature is measured for feedback

Behavioural interventions:

• Aim is to reduce disability by changing environmental contingencies that influence pain behaviour
  • Reinforcement of adaptive behaviour
  • Withdrawal of attention or other rewards to pain behaviour
  • Analgesic medication at set times rather than in response to behaviour
• Operant theory: pain behaviour may be established and controlled not only by the experience of pain but also by how others respond to expressions of pain
  
  • Pain behaviour reinforced by expressions of sympathy

Cognitive-behavioural interventions:

Behavioural programmes may indirectly change pain-related cognition: mediating our emotional and behavioural responses to pain

• Cognitive-behavioural therapy (CBT):
  • Help them to become ‘resourceful problem solvers’ and move away from feeling unable to cope
  • Identify the relationship between their thoughts, emotions and behaviour
  • Strategies to manage pain, emotional distress and psychosocial difficulties --> develop effective and adaptive ways of thinking, feeling and behaving
• Self-instruction training: change the commentary in their head at times of worry or concern to a more positive commentary
• Identify thoughts emotional distress or inhibiting behaviour and challenging them by looking for contrary evidence, treat them as hypotheses
• Strategies for coping intense pain:
  
  • Identify the pain trigger
  • Review my alternatives --> remind myself to keep calm
  • Distracting activities
  • Long, hot shower
  • Relaxation or self-hypnosis tape
  • Positive self-talk
  • Pain-modification imagery

Pain management clinics:

• Doctors: expertise in the pharmacological and even surgical treatment of pain
• Physiotherapists: develop exercise programmes
• Occupational therapists: consider how they can improve their day-to-day activities
• Specialist nurses: develop pain management plans
• Psychologists: also contribute to and develop such programmes