[imark3000]

Tremor is mostly not responsive to dopamin enhancement therapy. I only complain from tremor, so why my neurologist perscribed a massive dose of Sinemet which did not improve my tremor at all after one month of use?
Imad

The following research offers insight in tremor causes which are not related to dopmine!
New Discovery On Cause Of Tremor
In a new discovery, UK scientists have found a mechanism in the spine that counteracts the brain waves that produce tremor: they suggest the discovery could help around 1 million people in the UK who suffer from shakes and tremors.

A paper on the research that led to the discovery, which was funded by the Wellcome Trust, and conducted by scientists at the Institute of Neuroscience at Newcastle University, Newcastle upon Tyne, was published online ahead of print in the 1 June issue of the Proceedings of the National Academy of Sciences.

Most healthy individuals have experienced mild tremor, it is not uncommon when we feel tired, hungry or nervous, but more severe forms can be a symptom of neurological disease, including Parkinson's, Multiple Sclerosis and also Essential Tremor which is usually a disease of old age but it can also affect young people and it often leaves patients unable to walk unaided.

Dr Stuart Baker, professor of movement neuroscience at Newcastle, told the media that:

"We don't fully understand the brain systems causing these tremors but they can really have a massive impact on someone's quality of life. They lose their independence and can't do something as simple as make a cup of tea."

Baker explained the approach they took in their research: instead of looking at why people have tremors, they decided to investigate why most people don't have them.

He said that the part of the brain that controls movement produces brain waves the work at 10 cycles per second, so in theory everyone should have tremors that have that frequency.

In fact we do, said Baker, but the tremor is so smal that we don't notice it. So he and his team wondered if there was another process at work, one that countered the effect of the 10 cycles per second.

For their study, Baker and colleagues used macaque monkeys: they taught them how to move their index finger backwards and forwards very slowly, which exacerbated the natural minor tremor that we humans and our primate relatives have in common.

They then recorded nerve cell activity in the brain and spinal cord as the animals performed their slow finger movements.

The results showed that not only was the rhythm of nerve cell activity in the brain and spinal cord oscillating at around the same frequency as the tremor, but that the spinal cord was exactly out of phase with the brain, effectively cancelling out its oscillations and thus reducing the size of the tremor.

The researchers wrote that:

Convergence of antiphase oscillations from the SC [spinal cord] with cortical and subcortical descending inputs will lead to cancellation of approximately 10 Hz oscillations at the motoneuronal level."

They concluded that:

"This could appreciably limit drive to muscle at this frequency, thereby reducing tremor and improving movement precision. "

Baker said there are many types of disease associated with tremor, and perhaps in some of these the controller in the spine malfunctions and that is what actually leads to tremor.

In other diseases, he said, we already know the cause of tremor is a problem in brain regions that produce abnormally high oscillations.

"But even then, the spinal system we have discovered will reduce tremors, making the symptoms much less severe than they would otherwise be," he added.

The researchers suggested that the more we understand about how the spinal controller works, the better chance we have of developing treatments that adjust it to work better and thereby reduce the levels of tremor that patients experience and improve their quality of life.

"Spinal interneuron circuits reduce approximately 10-Hz movement discontinuities by phase cancellation."
Elizabeth R Williams, Demetris S Soteropoulos, and Stuart N Baker.
PNAS, published ahead of print June 1, 2010.
DOI:10.1073/pnas.0913373107

Additional

[reverett123]

I have dabbled with brainwave entrainment for several years and have in the past few weeks gotten more serious about it. There is ample evidence of widespread disruption of different areas of the brain in PD. Music, dance, tremor, motor function all are tied together by this. If it turns out that wave disruption inhibits dopamine production in the SN I am going to get excited.

Remember that sense of smell you used to have?
"PITTSBURGH—Timing is everything. For a mouse trying to discriminate between the scent of a tasty treat and the scent of the neighborhood cat, timing could mean life or death. In a striking discovery, Carnegie Mellon University scientists have linked the timing of inhibitory neuron activity to the generation of odor-specific patterns in the brain's olfactory bulb, the area of the brain responsible for distinguishing odors. "

Got your mojo working?
"In a finding that contradicts current theories behind Parkinson's disease, neuroscientists at Duke University Medical Center have discovered in mice that critical nerve cells fire all at the same time and thus overwhelm the brain's ability to control the body's movements."

Wanna' get a move on?
"The most significant finding is that in Parkinson's disease synchronized oscillatory activity in the 10- to 35-Hz band (often termed "beta-band") is prevalent in the basal ganglia-thalamocortical circuits, and that such activity can be reduced by dopaminergic treatments. The entrainment of large portions of these circuits may disrupt information processing in them and may lead to parkinsonian akinesia (and perhaps tremor). "

Bang a gong?
"One of the most exciting findings in this research, however, may be the evidence that the interaction between auditory rhythm and physical response can be effectively harnessed for specific therapeutic purposes in the rehabilitation of persons with movement disorders."

[reverett123]

In reading about some of these new ideas. the picture of PD as some result of inner conflict keeps recurring in my mind. This conflict takes many forms. A cramped muscle is a type of conflict. So is a pair of muscles that no longer work together. Freezing is a conflict that is an inability to decide, in this view. Tremor is an attempt to do two things that are mutually exclusive.

There are widespread disruptions of brainwaves in PWP. Widely separated areas of the brain depend on synchronized watches to function together, but "the center cannot hold" and disharmony results. DBS attempts to restore the balance with limited success.

What is the impact of DBS on the substantia nigra, anyway? Does it begin to make dopamine again? If not, then what IS going on? Is the SN essential for the clock to function? Or is the clock essential for the SN?

This disharmony is widespread in the PD brain. So is PD damage. There is so much more at work than dopamine and the SN.

PD is a disharmony of the entire system. Conflict breeds stress and vice versa. Where is the origin? Is it in the mind of the child attempting to resolve love and fear emanating from the same individual? Is it in the brain of the young woman sacrificing Self for Family one time too many? Or in the horrors the young man brings back from War?

There is much to ponder here.