In Anthropology the term emic is used to describe a society from within. By means of participating observation, the researcher tries to understand a group of people from the inside. This brought me to the idea that maybe it would be fruitful to apply this concept to the problems posed by Parkinson’s disease. Medical researchers have a lot of precious tools at their disposal, but these all operate at the outside. Patients can feel the pain or annoyances a disease causes. Of course a doctor or a researcher will pose questions to the patient. This could work well if you know what a disease is like. If however there is a lot that is not known of this disease and a patient is able to wander through his disease, he can add substantially. He should be trained to describe as accurate as possible what the nature of the symptoms of PD is. I’ve tried to do just that and it made me doubt seriously about the current levodopa theory.
The method I use to investigate PD is that I ask the same question, over en over again: “what do I feel when I do something” . This one of a series of articles where I try to describe the feeling of PD. I hope this will bring field professionals to ideas to solve the mystery and conquer Parkinson’s disease.
During the night I don’t take any medication. Early in the morning, when I rise, I often have the impression my Parkinson’s disease is almost gone. I can stand on one leg an put the other foot in my pants. I can turn my head to the left, and immediately after that to the right. I can open my hand an close it again. Sadly enough this favored condition doesn’t last much longer than half an hour.
If I don’t take medication my condition will change fast. It is getting harder and harder to move. The first symptom I usually experience is that my tongue starts to quiver. From the survey “images of parkinson’s disease” I know other patients do not have this as a premier symptom. Soon after that, walking will be difficult, my face will get stiff. I will not be able to stand up from my chair, and if I stand my right leg will suddenly not be able to carry my weight causing me to fall.
I usually avoid this second state by taking medication. About 20 minutes after I have taken levodopa I enter the “on”-state. I can move again hooray! But this kind of movement isn’t quite what I expected. It is so overdone. If I move my head to the left, this will work, but if I want to move my head to the right after that, this seems impossible. The muscles of the original movement won’t give in. The muscles that want to cause the rotation in the other direction, have to use brute force to accomplish this. In fact all the “to and from” kind of movements, except pedaling on my bicycle, don’t work properly. It’s is better than no being able to move at all, but it is not the relief I expected. By the way, the fact that pedaling on my bicycle goes wonderfully well, might be a key to understanding the mechanism. In pedaling you only have to push one leg. This action will return the other leg to the starting position, no antagonist needed!!
I will make an attempt to analyze what is happening to me. The thesis I want to launch, is that Parkinson’s disease has to do with a flaw in friction management. To hold the different bodyparts in a fixed position without using too much energy, friction in our muscles should be high. If, on the other hand, you want to make precise movements, friction should be as low as possible. The concept of friction in mechanics is important and it should be reckoned with when planning movement. Without friction, cars wouldn’t be able to ride or brake. Let’s do an experiment. I have an electric Philips shaving device. The power chord is twisted and curled making it more or less elastic. If you try to drag the shaver by pulling at the power chord, the power chord is stretched say 6 cm before the device starts moving. If the main electric switch is turned on and the shaver starts trembling, the power chord is stretched only 3 cm. It becomes much easier to move the object when this object is vibrating. This makes it much easier to make precise movements.
When you want to move a heavy chest it is easiest to do this with short, powerful pushes. It is hard to control how fast it is moved, but move it usually does.
If I am in the state where it is hard to move, strangely enough, I can run, I can play tennis or box with my son and perform reasonably well.
Vibration can be seen as a series of pushes in opposite directions. By adjusting the frequency and the force (amplitude) friction might be reduced to almost nothing.
Patients with parkinson’s disease often have a tremor that stops when a movement is going on. Could it be that a healthy person, who wants to make a move, trembles too? Possibly his tremor cannot be noticed because it is so quick. Someone with parkinson’s disease cannot make a “to and from”-movement fast enough (Dysdiadochokinese). The amplitude rises and the frequency lowers and the tremor becomes evident. So it is wrong to say that someone with parkinson’s disease has a tremor while in fact his tremor doesn’t function anymore. Could that be true?
If a parkinson’s patient is given levodopa, the friction of his movements is reduced. As this is not the real solution, the ongoing disease will demand that the friction will be lowered even further. The result is however that the movements lose their stability. They become gliding and exorbitant. The least effort will cause exaggerated movements called dyskinesia.
This article doesn’t solve the question why “to and from” movements no longer function properly. Maybe there is an expert in the field who will find some inspiration here. What I wanted to show is that a patient has a source at his disposal that is unique and that might be crucial in solving the parkinson’s mystery.
Van den Bosch, A.P.M.
The Dopamine Theory of Parkinson’s Disease, http://parkinsonhuis.nl/onderzoek/Th...%20Disease.htm
University of Frankfurt.
The effects of random whole-body-vibration on motor symptoms in Parkinson's disease.
Journal NeuroRehabilitation. http://iospress.metapress.com/content/c9gvmedjj1mnk2e9/
Christopher Rickards1 and Frederick W. J. Cody
Proprioceptive control of wrist movements in Parkinson’s disease
Reduced muscle vibration-induced errors
Brain (1997), 120, 977–990http://brain.oxfordjournals.org/cont...6/977.full.pdf