Pain is not just pain
To feel pain is a natural alarm signal given by our body to show that something goes wrong. Without pain sensation we would not know that we are hurting and we might die from infections. Pain is therefore vital.
Pathological pain is the result of an injury or malfunctioning of the sensory nervous system. This can become chronic (> 6 months).
There are various forms of pathological pain. The most well-known are neuropathic pain and phantom pain.
How does pain occur?
There are 3 pain systems in our brains, two of whichare ‘pain-feeding' systems. The first system (lateral system) gives us information about the location and the intensity of the pain. The pain stimulus runs through neural pathways in the periphery to the spinal cord and is transported from there to the sensory cortex in the brain.
The second pain system (medial system) determines the emotional and motivational value of the pain. Not the sensory cortex but the anterior cingulate cortex, the amygdala and the insula play an important role in this.
However, there is also a pain-suppressing system that moves anteriorly from the pregenual anterior cingulate cortexes to the reticular nucleus of the thalamus, the periaqueductal gray, and from there to the spinal cord to block incoming painful stimuli.
Whether or not pain is perceived depends on the balance between pain delivery and pain suppression.
In pathological (neuropathic) pain there is an increased activity of the pain-feeding nerve pathways and a paradoxically increased activity of the pain-suppressing pathways. However, the increase in pain delivery is greater than the pain-suppressing effect, so that the patient still continues to perceive pain.
Fibromyalgia is characterized by poor functioning of the pain-suppressing pathways. Without a clear increase in pain delivery.
How is chronic pain treated?
First, the cause of pain must be checked and possibly treated. There is no point in applying neuromodulation when the pain is caused by a cut wound. If the cause of the pain cannot be found or treated, the treatment will focus on the symptom itself: the pain.
Symptomatic pain treatment usually consists of administering medication such as painkillers and anti-inflammatory drugs. With more severe pain symptoms, medication is given that affects the brain, such as anti-epileptics and antidepressants. The disadvantage of medications is that they can have unpleasant side effects. On the other hand, habituation can occur whereby the dose of the active product must be increased.
Non-drug treatments can consist of different forms of neuromodulation (tDCS, TMS, HD-tDCS, sLORETA-Neurofeedback, etc.).
Neuromodulation focuses on restoring the balance between pain delivery and pain suppression. On the one hand, the pain relief can be treated at the level of the dorsal anterior cingulate cortex and / or the sensory cortex. On the other hand, the pain suppression can also be enhanced at the level of the pregenual anterior cingulate cortexes.
A qEEG can help us determine which neuromodulation technique could have the most effect.