View Full Version : Can we see if chronic pain is all in the mind?

04-11-05, 01:52 PM

IT IS THE hardest thing in the world to get inside somebody else’s pain. Only those who have themselves endured the incubus of chronic pain can begin to engage with sufferers. It is all too easy for the fit person to grow impatient at the obsession, the erosion of personality and the loss of joie de vivre that are the lot of the person in torment. One person in six these days is beset with chronic pain, and half of them do not find a good solution.

Although pain is one of the most common symptoms doctors see, they are in general rather poor at treating it. As with any high-flying professionals they do not like to admit failure, so patients with intractable problems all too easily have them labelled as psychosomatic.

Many patients get extremely upset at the suggestion of a psychological component either in the symptom or in the measures used to address it. They do not relish being told that it is all in the mind. This war of perceptions - which has beset the management of fibromyalgia, myalgic encephalomyelitis (ME) and related conditions - in which patients and psychiatrists are locked in bitter combat does nothing whatsoever to alleviate genuine suffering.

Now, with the improved multidisciplinary approach to treatment that has fostered pain management clinics, and with an improved understanding of symptoms through brain imaging, things should get better. It is vital to appreciate that prolonged exposure to agony is itself physically detrimental. It follows that the last thing patients in pain need are waiting lists. The longer the symptom continues, the worse the resulting brain/emotional/neurological rewiring that goes on. Discomfort thresholds drop, anxiety and depression intrude, and the perception of pain is magnified - the most vicious of circles begins.

New brain-imaging techniques are capable of showing the presence of pain, and are beginning to unravel the secrets of unexplained pain - and why some people feel physical assaults more severely than others. Acute pain serves a biological purpose, causing reflex withdrawal from its cause and encouraging rest of an injured part. With healing, acute pain usually subsides, but sometimes it does not, and a chronic syndrome results. Some of these have long been recognised, such as phantom limbs after amputation, post-herpetic neuralgia, chest pain after thoracic surgery, post-head-injury headache. They all have a common factor: nerve damage.

Spinal cord injury is particularly likely to result in a chronic pain syndrome. Modern brain scanning techniques show that when this happens, damage to spinal nerves and pathways is associated with changes in parts of the brain, especially the cerebral cortex (the "thinking" part) and the thalamus, a more primitive part. Such injuries and their knock-on effects in the brain lead to both: a) sensation of pain where no stimulus is received, and b) excessive pain felt on minor stimuli. The pathology of the central brain in these cases - maintaining and augmenting the sense of pain with all its attendant emotional responses - is directly caused by constant niggling impulses from the damaged spinal nerves. It may be that this mechanism is the basis for chronic debilitating back pain after injury, one of the commonest reasons for people consulting their doctors and being off work.

RESEARCH USING brain imaging techniques measure blood flow and chemical changes that indicate altered activity. These show that pain perception is much more complex than anyone could have imagined. There are no discrete nerve pathways, but instead there is a network of interacting message systems involving sensory, motor, memory, emotional, attention and anticipatory functions, all of which can modify the experience.

This is the basis for the multidisciplinary approach to pain management, which can involve relaxation therapy, yoga, breathing exercises and distraction by TENS machines. People can be shown images of their own pain reception on scans, and can see it responding to such pain relief measures. It is hugely empowering. This meshing may explain the placebo effect as well as the strong emotional content of cardiac pain, the "sense of impending doom" that can accompany a heart attack.

The most useful message seems to be that chronic pain is correlated with, and presumably caused by, nerve damage.

This could provide an explanation for many groups of suffering patients whose genuineness has been called into question in the past: people such as those with ME, fibromyalgia and Gulf War syndrome 3 (chronic pain).

In all these conditions, brain scans have consistently shown lesions, and no-one can be in any doubt that there is a physical basis for their pain as well as an explanation of the severity of it in the apparent absence of local pathology. In Gulf War syndrome, there was a multiplicity of nerve poisons to which the veterans were exposed. In ME the cause of the damage is less clear, but could be either chemical or infective.

The new knowledge opens the way for imaginative forms of treatment, which are best tailored for the individual, and may well incorporate complementary techniques.

01-25-06, 02:20 AM
It is all in the mind. That is where the brain registers pain. :P </smartass>