Copernicus rocked the world by declaring that the earth rotated around the sun. Despite the veneer of magnificance of earthly man made organizations which commanded respect, the sun could care less. We are learning that the Wizards of Oz have been spreading falsehoods about pain, as well. Time to go back to Kansas, where people are simple enough to believe pain is pain.
It took a long time for the old ideas to die. After all, they had been around since Ptolemy, who was not even questioned by Aristotle. Predating geocentric astronomy are the old ideas about pain, which persist even today. Since humans no longer live in mud huts, and even carry MP3 players around, perhaps we could take a look at pain chemistry for some better information. We of the Central Pain condition must now tell the world that pain rotates around CaV2.2 ion channels, NOT around our imagination. Can the world endure this idea? Perhaps, since they themselves know perfectly well that pain exists, that it hurts, and that it is mainly physical, NOT psychological. The psychological distress they observe is because we HAVE pain, not the source of it. We aren’t revolving around the pain. The pain is revolving around us.
It often takes one of their own to change a group’s thinking. Copernicus was a priest from Poland who held the position of “canon” at a major chapel. His hobby was translating Greek poetry into Latin, not exactly an MTV type of guy. However, he did have a brain and did have his “eyeball”, which was his instrument. Using his blinding intellect, he noticed that the earth rotated. This astounding information was unwelcome, antireligious, heretical, and completely true.
Now we come to the people who think pain, especially pain which lasts, must originate in the imagination, put there by some misplaced stress or moral weakness, which so pervades the whole apparatus that we THINK we are in pain. The news of the day is that if the brain THINKS it is in pain, it IS in pain! Pain is after all a construct. Cells down in the big toe do not know they are in pain, only the brain knows this. Oddly the brain itself is insensitive to pain. It can only create the sensation with regard to other parts of the body. The one exception to this is Central Pain, wherein the brain gains the power to feel pain within itself, and the axons (long runs) of sensory neurons gain the power to inititate a generator potential (which kicks off action potentials of pain) within themselves, something which normally only nerve ENDINGS can do. CP pain in the brain itself originates with perineural acidosis in the thalamic VPL/VPM nuclei as well as some thalamic intralaminar nuclei, AND from the subthalamic nucleus. There is also pain very close to the brain if the dura (lining of the brain) becomes hyperalgesic through injury to the descending tract of the fifth cranial nerve in the cord, anywhere down to C5, probably due to interneurons with connections higher in the cord (source P.D. Wall).
The experts are still debating whether the failure of the brain to inhibit CP is due to:
1) confusion in processing the signal (ie. the bizarre signal coming up convinces the brain really severe pain is going on, so it refuses to inhibit it),
2) whether the nerves in the body are severed and CANNOT receive inhibitory messages comging down from the brain, or
3) whether the injured neurons cannot manufacture KCC2, the carrier of chloride to the cell membrane, chloride being the inhibitory ion of neurons.
The vermis lights up in an attempt to supress central pain, but this does not settle the question of why the cerebral cortex (frontal, parietal, insular) fails in central pain suppression. There is of course the possibility that the brain is attempting mightily to suppress CP and is in fact doing so to a degree, but that the nerves are so overwhelmed by the abnormal Nav 1.8 ion channels and acidifying pain exciter chemicals that the brain CANNOT inhibit the out of control neurons.
There is, however, unanimity on the fact that pain exciters have occupied the dorsal root ganglia and spinal dorsal horns. The chemicals are positively identified, predictable, known pain exciters, and there is a high concentration of them in the DRG and dorsal horn. Acidifying cytokines have also been identified in the thalamus. The group includes CREB, TNF, arachadonic acids, fatty acids, PKC, GABA metabolites which prevent the normal action of GABA (a pain inhibitor) itself, and a witches brew of other nasty molecules.
It is also known that destruction of the VR-1 aka TRPV-1 channel in neurons by resiniferatoxin stops the burning instantly and permanently, at least in peripheral nerve injury pain. Blocking the related Calcium channel, CaV2.2 with conotoxins also stops nerve injury pain but preserves ordinary pain.
Ron Tasker, the great Canadian pain neurosurgeon who discovered that pain travels in the spinothalamic tract, also noted that in normal people radiostimulation of the cord in the neck caused no sensation, but recreated CENTRAL PAIN in those who already had CP. The sensation was that of dysesthetic burning, dyesthesia meaning unusual. It is appropriate to call dysesthesia bizarre because nerve injury pain involves a MIX of pain sensations which is not exactly like any one of the individual components. (Just as mixed colors don’t end up like any of the contributors). Burning being the most durable of pains, it is also the major component of dysesthesia, but CP is more than a simple burn.
Tasker’s discoveries did not exactly convince the world right off the bat. The Canadians, it seems, did not have instant credibility in the scientific world. This is ironic since the Canadian pain specialists now populate prestigious institutions such as Johns Hopkins. The word “McGill” University in the author’s CV gives credibility for publication today in any pain journal. It wasn’t always so. In the U.S., things were not much better, since John Bonica, the father of American Pain Research, did not receive widespread acceptance of his epidural block for nearly fifty years. After all, what is the hurry when the pain of others is involved. If Patrick Wall had not stepped in, Carl Saab would have been rejected when his early research revealed that the cerebellar roof nuclei attempt to suppress Central Pain. For years, the idea of “One neuron, one neurotransmitter” was seriously believed, while today any given neuron is known to produce many different types of chemicals involved in neurotransmission.
Looking back, it is amazing how accurate Tasker was in his investigations. What could possibly explain this except that he used his brain instead of following what everyone was saying and had been repeating about pain from the time of the Dark Ages, except of course for anyone who actually studied the chemistry of it.
During the Dark Ages, people were convinced that God existed, but there were a lot of things about Him that you wouldn’t like, such as that His favorite activity was inflicting misery on humans, who deserved it, of course, or else why would God “impose” it. There was little doubt in the ascetic mind that God’s indifferent plan was to sit listening to prayers for relief with emphatic silence, spurning the creatures he had formed, a Being who would hear you when you were happy, but slammed the door and bolted it when you were desperate for help. What could anyone do but mirror this indifference by telling people if they had pain, they darn well deserved it.
The psychologists got God off the hook by transferring the blame over to the pain sufferer. THEY were giving themselves the pain because they willed it. No we don’t. I don’t will Central Pain. I will anything BUT central pain. This should be obvious, just as it should have been obvious that the earth was rotating, just as Aristarchus had said it was, and apparently the ancients knew it as well. However, few people will take on a priest, particularly in the Dark Ages. Now we find that those clothed in the robes of the academic priesthood, at least as they receive their diplomas, which not coincidentally are exactly the same robes which clothed the ecclesiastical priesthood in the Dark Ages, feel we should maintain their pre-Copernican ideas about pain. Some of their own are challenging old ideas now, thanks to chemistry and a grasp of the obvious.
Here is a novel idea, God actually wants us to be free from pain, but has placed us in a world where free agency and choice exist, for a purpose and OUR greater good. Among the tasks God wishes to see performed here are to feed the hungry, clothe the naked, comfort those who stand in need of comfort, and to end the pain of those who must endure it. Such an idea would be consistent with a loving God. It is therefore reasonable. Let the dissenters explain their cynical superior attitude toward those in a pain state. You must decide for yourself. Is it God’s work to cure pain, or is it His work to ignore, accuse, or malign those with a pain state?
However much we might want to honor the behaviorist PhD, the chemistry simply will not support it. The dorsal root ganglia of those with nerve injury pain are literally packed with abnormal ion channels and acidifying chemicals known to cause pain. Since everyone we have met with CP desperately wants to be rid of it, we simply don’t know where they get the idea CP is self-flagellation. Perhaps they need to rethink matters, including what they know about themselves, and ask whether they really believe those poor souls going to the pain clinics for CP are crazy or whether they might, just might, actually be in terrible pain. Those of you with CP already know the answer.