Neurological question

I am not asking for advice, nor for uninformed speculation, but only from someone who actually knows the answer.

There is a woman who conducts a choir here in Montreal. She has fairly severe palsy, employs a wheelchair, and shakes constantly. Except when she is actually conducting. She gets our of the chair and perches on a high stool. When she is actually conducting, her body is rock solid and she waves her hands to the beat, looking like any other musical conductor. The piece ends and she throws her arms in the air, still rock solid. She holds this pose for maybe 2-3 seconds and then starts to shake. She lowers her shaking arms and then announces the next piece. Repeat until end of concert.

Does anyone here understand what is going on at the neurological level? Is there simply an undamaged musical center that takes over and then releases? It would be interesting to know if she can dance. Could she somehow train this center to take over all the time? Dance through life? 'Tis a mystery to me.

It sounds like the same concept as the stutterer who can sing without problems. My mother had Parkinsons and supposedly one of the aids to concentrating the ability to start moving was following a dot from a laser pointer. (Catnip apparently did not help, though).

Who knows? Rote memory taking over from conscious control?

I believe we’re likely to see several posts here detailing similar anomalies. I’ve read that there are several hypotheses that attempt to explain these situations, some related to behaviors that activate some neurological pathways while tamping down others, but ultimately, it’s a mystery at this point.

And I’ve read similarly about dealing with symptoms of multiple sclerosis. MS patients sometimes have trained assistance animals to help out. If a patient suddenly finds that he can’t lift his foot, for example, the animal will poke at that foot with his paw, and this tends to help the patient get moving again.

The neurophysiology of movement and tremors is horribly complex and confusing. Here’s one attempt to explain the basics:

All clear now? Good. I’m not either. :slight_smile:

The simple answer is that tremors can be very function dependent because the problem can be specific to the connections to and/or from specific parts of the brain. For example there is writer’s tremor that only occurs with writing, a variety of musician dystonias that only occur while attempting to play the instrument, and even a primary bowing tremor.

This seems to be the negative image of those one. In those one area is affected, especially area involved with music; in this woman most areas are affected except ones related to conducting music.

I wonder … does she have a tremor in her voice when speaking? Music production shares much with spoken language production. (That study in jazz musicians engaging in a back and forth but I would imagine that conducting is neurologically not too dissimilar.)

Sorry that this is short of knowing the answer but hopefully it is still a step above an uninformed speculation.

People with Tourette’s are familiar with this phenomenon. Oliver Sachs once wrote about a surgeon who suffered from the disorder. He was virtually tic-free while performing surgeries.

The tremor of Parkinson’s Disease lessens, or disappears with intentional movement. Conversely, it is most prominent when the affected body part is at rest. This phenomenon is used to distinguish PD from so-called Essential Tremor.

It’s not totally relevant to the OP, but I’m reading this fascinating book by David Eagleman called “Incognito”, which talks about the hidden, subconscious aspects of our brains. He briefly talks about experiments done on spinal cats, which are cats that have a transected spinal cord. Put one of these kitties on a treadmill and it will walk as if its brain is in full contact with the limbs, which of course it is not. The take-away is that a lot of information about movement is stored in the spine. We just don’t have (conscious) access to it.

And that essential tremor decreases with alcohol consumption. But, unless I misunderstand, this is not the straightforward decrease with intentional movement: she tremors with other intentional movement; just not while she is conducting music, during which time it completely goes away.

IANAD, but very basically, there are two kinds of tremors, resting tremors, and intention tremors. Whatever the underlying cause is, intention tremor is more common, and some people have both. This woman has resting tremor with no intention tremor.

If I knew more, I could tell you that there were certain underlying causes that were automatically eliminated, with RT but no IT, however, I know about this only from having dealt with a whole lot of disabled people in their day-to-day lives, so I know a lot of terminology-- I can tell you a whole lot about seizures and how to handle them, but I don’t know much about the neurology of epilepsy.

Some people with resting tremors in their hands or face that are very bad do things like squeeze silly putty, and chew gum, but that’s if they either find the tremors annoying, or they have “big” tremors, and might knock something over, or are self-conscious.

Ah, I misunderstood. I thought she lost the tremor with any purposeful activity, with conducting being the extreme example for her. If her tremor disappears only with conducting, then I haven’t got a clue. (If it disappears to some degree with all intentional movements, PD is still a possibility.)

It depends on the definition of “rest”: many movement disorders don’t show any disordered movement when the person is sleeping.

A number of years ago I was in a fairly rigorous (for me) dance number in my chorus’s concert. I was also suffering from an excruciating torn achilles tendon. I remember waiting offstage in agony, and I remember limping offstage after the dance. But during the dance number itself, I was in no pain whatsoever. I take it as meaning that our brains can’t multitask as well as we think; that it prioritizes, and disregards lower-priority functioning, at least on a temporary basis.

Interesting and I even sort of followed your quote. She did not have a speech tremor as I recall.

The only intentional movement I saw, aside from the conducting, was wheeling her chair and I think she still shook. What was amazing was that when a song ended, she threw her hands up in the air and stayed rock solid for a few seconds, then suddenly began to shake. The transition from that rock solid position was sudden and startling. Then she lowered her arms, still shaking.