The Pain Gate and pain processing

Use the Pain Gate worksheet, Peripheral and Central Sensitisation Figure 1.6.

One way to explain the persistent pain problems is by using the Pain Gate theory.

“Acute lesions result in pain signals, which travel from the injured area to the spinal cord. Certain nerve cells interact in the spinal cord where the impulses are relayed to nerve pathways that transport them to the brain. This relay function acts like a ‘gate’ that opens for the signals, which then travel upwards to the brain for further processing.

“Physiological pain sensations after an injury to the head and neck mostly stem from lesions to the scalp, skull, muscles, arteries, some cranial nerves, brain membranes and other tissues, but not from the brain itself. Any of these sensations are also relayed in the spinal cord.

“Pain can only be perceived via the brain’s pain-processing systems. There are many brain systems that are responsible for identifying, analysing and responding to pain signals. The perceived pain signals are converted by the brain’s Action Systems and are then transferred back down through the Pain Gate. If the gate opens, then the site of the lesions receives some feedback. In this way, the body can monitor and influence the natural healing process.

“In persistent or chronic pain, the process of pain sensations, pain monitoring and feedback continues, despite completed healing of the injured area. The pain-brain circuit develops an automatic habit and the pain perception continues.

“This might be because the brain’s signal transmission may be malfunctioning due to micro-changes on the chemical-electrical informationprocessing mechanisms. Additional processes (such as hyper-arousal, inappropriate posture, avoidance of movement, etc.) maintain pain processing and prevent them from calming down after an acute lesion has healed.

“Your body experienced a significant onset event (i.e., the accident), which caused an acute micro-injury to head and neck tissue. The event was encoded as a threat to your well-being or even survival. As a result, vigilance towards external stimuli and internal sensations that could potentially indicate danger was increased. This means that a high quantity of head-related sensations (not necessarily painful sensations) get through the Pain Gate, engage the Action Systems and enter the feedback loop. The brain activates networks that specialise in pain perception, processing and actions to take.

“The redundancy of this process in the form of chronic headaches can be described as a continuously sounding fire siren long after the fire and damage have been cleared up. It is now necessary to employ different methods to turn off the constant alarm signal and to reassure the body that the ‘alarm systems’ can shut down again. They will still be able to function effectively in the case of real danger.

“The constant perception and experience of pain sensations leads to an improved, but unnecessary, ability of certain brain regions to detect and analyse them. That means the brain, which enables us to feel pain, becomes more and more skilled in letting us know about the pain. This is also called Central Sensitisation.

“These processes enable us to detect and remember the pain sensations in great detail. Constant headache syndromes are like an automatic skill or a habit that the brain has become better at doing. Headache management strategies aim to undo these inappropriate habits.

“The brain can help us do many useful things. Purposeful activities can occupy brain systems and divert the focus from pain processing. Such mind-absorbing activities are also coordinated by the Action Systems, which can positively override and distract the pain mechanisms.

“The less the pain stimuli are processed in detail by pain perception systems, the higher the likelihood that, over time, conscious awareness will be diverted and focused on more helpful behaviours, which, at the same time, dampen down and distract pain processing. This results in central reorganisation.”

Central Sensitisation and Central Reorganisation

Use the Peripheral and Central Sensitisation Figure 1.6 and my well-being actions worksheets 1 & 2

“A shift in lifestyle and the use of therapeutic techniques is required to balance the body’s resources and the cognitive capacities for information-processing with the demands that they are exposed to.

“Specific methods are required to redirect brain systems to properly interpret physical sensations and to reduce the unnecessary processing of meaningless pain signals, as well as to generate more helpful habits and behaviours. In this way, the brain is learning new options of responding. “The habitual pain reaction can be dampened by alternative behaviours. These must be learnt patiently and consistently practised. Headaches are powerful signals and spontaneous pain responses are not easily overridden, as they remain vital to one’s survival.

“In addition to that, you experienced an accident. As discussed previously, the automatic ‘alarm systems’ fire in response to a vast range of onset event-related stimuli and images, not only to physical or pain-related ones.

“Initially, it is important to become aware of the sensations associated with headaches in a passive and non-judgemental way in order to eventually reframe their meaning in our life. Coping habits need to be reshaped; for instance, habits to respond to headaches and headache-related worries immediately and with an ‘all or nothing’ approach, e.g., by taking medication or ignoring the pain.

“Applying modified methods of responding to headache sensations, thoughts and behaviours means that you can learn to overcome the intrusive and uncontrolled focus on the pain. This requires an enormous amount of trust that your body will still recognise and respond to real danger, should such a situation ever recur.

“The Pain Gate worksheet illustrates the pathway between the pain stimulus and the brain’s perception of it. Some factors that open and close the Pain Gate are listed. It is useful to find out which of these would work for you.

“The my well-being actions worksheets summarise how important values in life, life goals, purposeful activities and coping strategies can strengthen the brain’s abilities to alter responses to pain perceptions. As a result, such actions close the Pain Gate and fewer sensations can be noticed.”

“What are your well-being actions?

• - What do you value in life (e.g., social relationships, achievements)?
• - What are your life goals (e.g., having good friends, having a good job)?
• - What activities give you a sense of purpose (e.g., helping your friend fix their car, being reliable at work)?
• - What activities do you enjoy that really take your mind off things?
• - How do you achieve a deep sense of relaxation?”