Frozen stance, tremors and other dementia fun: An Engineers Perspective

Greetings to all eight of my readers; make yourself comfortable because this I think is an important one to get your head wrapped around.

I find myself at surprising intersection between engineering and disease, or at least my own. I have been a software engineer for more than two decades and hardware long before that. I only state that in order to impress upon the reader that after so long I have a pretty good sense of how machines think and how they work, particularly when it comes to computer systems.

Since being diagnosed I have used my own condition as a laboratory of sorts to try and understand what is happening to me. It has always been the case with me that the more I understand a danger or threat, the easier it is to deal with. Others may be that way too, I don't know.

One of the major categories of things I have been trying to sort out is the seemingly random nature of the motor skill problems, a blessing from the Parkinsons side of things: frozen stance (where patient seems locked into a position for long periods of time), tremors, gait issues and general eye-hand coordination issues.

Lewy Body screws with you on two planes:

* The Physical Plane: where the Parkinsons stuff tends to surface: walking, speech, coordination or the opposite of all that, the dreaded frozen stance.

* The Mental Plane: Basically anything that can go functionally wrong mentally does go wrong on a daily basis, in fact your own mind becomes the living example of Murph's Law about anything that can go wrong, will go wrong.  

Todays story concerns the physical plane. When asked to explain the physical side of things, doctors tend to fall back on incomplete explanations like:

Why You Have Tremors/Gait issues/Etc:
1. You have dementia.
2. ???

Now as I have said I was an engineer in life and specifically I ended up specializing in systems engineering or how the parts of a large complex system work together. I have done it so long that it has basically influenced how I think and view the world around me.  And so it was that when these things started happening to me, I saw them in a different way, from the inside.

Things look very differently on the inside; you can see your body doing things, screwing up as if you were watching a movie of someone else's hands, feet, etc doing things not intended by the manufacturer. At first it was horribly frustrating, trying to do the simplest things you have done since an toddler only to see your own body rebel against you and cause a mess of things. We all know this feeling and was the direct cause of many dinner plates converted to projectiles in the beginning. Like I said, understanding is important to defusing this particular bomb.

The Good News:

I was thankfully able to take a step back and look at the larger problem, much as I had for years with computers. Much to my surprise, a pretty obvious and clear pattern jumped out at me from a diagnostic standpoint that I wish to share with others before I am no longer able to. It was one of those "A-Ha" moments that makes the whole issue of physical problems much less demeaning and depressing. They still will happen, they will still get worse, you will still die but you might spend the time between now and then hating it just a little bit less. The other hope is this explanation might trigger something with a neurologist somewhere. The answer matches a problem in computer operating systems design and since the problem is absolutely fixable there, perhaps this might suggest a more systemic approach on the medical side.

But first, some necessary systems training...

A little high-level systems understanding is required but trust me: its actually pretty simple and once you see how this works, the reasons for Dads frozen stance or Moms slow shuffling gait will likely become clear as a bell.

If you look at a typical home computer system you actually have far more than a single computer:
1. Main CPU/computer
2. Monitor
3. Keyboard
4. Mouse
5. Printer

...and perhaps even more but this is enough for this explanation.  Actual computer systems and most other non-trivial systems are generally built around 1-4 Central Processing Units or CPUs (think:Intel, AMD, etc) that control literally everything in the system. Not directly so much but thats getting too low level for this.  The CPU is the "brain" of the system or perhaps more accurately the CPU and Operating System (Windows, Linux, etc). The CPU controls everything (printer, monitor, etc) using the same method that the components themselves use to talk to the CPU: Messages.

Messages are like tweets in a way, brief notes about some extremely minor subject. The best way to explain this is by example.

Say for instance you sat down at your computer to work and wanted some music you had on a CD. You might use the mouse to right-click the CD icon and select "Eject" after which the door opens and you can insert your CD. You then might click on a "Play" icon and the door shuts, the disc spins up and track one begins streaming from your speakers.

As simple as that was, if you broke it down and looked at what was happening inside the computer you might see something like this:

1. Mouse detects that it has been clicked. Collecting the coordinations of the mouse cursor on the screen, the mouse sends the CPU a message like "This is the mouse and I was just clicked. It was my right mouse button and it was at these coordinates on the screen."
2. The CPU receives the message, translates that action to mean "wants to Eject CD" so it then crafts a message something like "Peripheral CD drive: open the door." and sends it to the device.
3. The CD drive gets this message and does as it is asked, the door opens. It is assumed something is inserted.
4. Mouse once again crafts a messages after you click "Play" similar to the first, "I was clicked, this time left mouse button and it was at these coordinates." and sends it to the CPU.
5. The CPU reads the message, understands the click->Play was on the music app and sends the CD the command like "Peripheral CD: close the door."
6. The CPU then starts the CD Player app and sends the message to start with track one: "MyMusicApp: Use CD Player as a source, read and play track one."
7. Once launched, the app MyMusicApp gets the above message and suddenly the user is hearing music.

Operating systems will vary but the core of a message usually is comprised of some fairly basic and unsurprising information:
1. Who the message is for
2. Who the message is from
3. Core message itself (open door, mouse-click, etc)
4. Supplemental information (mouse was clicked HERE, the mouse button was THAT, etc)

With these four things, any message that is needed can be constructed. With these four things, everything works as expected. As designed.

However if you look at the corollary of this, any alteration, any corruption of even a single part of any single message can have disastrous and certainly unexpected results. If you stick a USB stick into your computer and tell it to format it, the format message goes to the proper subsystem and your stick gets formatted. However change the address of that message and suddenly your main system drive is getting plowed over. Depending on the peripheral, the confusing commands might leave it in a form of brain-lock, unable to follow any commands until reset. I am sure you have seen the peripheral that just stops responding until you give it the three-finger salute or simple reboot. So there ya go.

There, that is all the theory. Not that bad. It lays out the general message handling/passing mechanism that drives most systems today.  If you generalize just a little you can see how a simple system like this could be used to manage almost anything, which is why its so widely used. Message to printer: print document X in directory Y. Modem: Dial number 12334567. And so on.

As a sort of segue, I would like to add that when you get good at understanding what a computer is doing as its doing it, you can almost see this message flow in your head. When something stops working you can almost see the message flow interrupted. When it does something unexpected, you can almost see the corruption in the message. When the CPU seems to stop responding, you can almost see the messages going in and out of it blocked by something. See enough of it over enough years and it becomes obvious.

So when my body started screwing up and I got over the "God dammit I could do this yesterday!" anger I took a step back and looked at the slow-to-respond feet or randomly moving hands or trying to will myself to finish straightening up and....nothing happening. Like my brain is screaming at the legs, spine, etc "GET THE F UP!"....and they are all mute. Not paralyzed, not broken or really malfunctioning on their own, simply deaf to messages. Or the brain is not transmitting them. Don't know, doesn't matter, the systemic cause feels obvious, the messages of the brain are getting trapped, corrupted and misrouted. I see that last one often trying to tie shoes or blow my nose (any task that requires left hand/right hand coordination to accomplish some task) and the right hand does what my left hand is expected to.

Classic example of the mis-routing of messages happened a little while ago when bringing two hot mugs of soup to my wife. I spilled the one in the right hand onto the right hand, burning it badly and causing me to yell out. Did I drop the burning soup? Nope, the left hand drops what it has, for no reason, other than what I suspected above. No other explanation. I get stuck getting up or whatever and its like I can feel all the message traffic just die and ....not sure how to put this...its like my brain is whispering the messages and the rest of the body can't hear.  So I can see myself stuck, I can will myself to get up like I have a million times since childhood and nothing happens.

And when I say message traffic dies down to nothing I mean it: I stop blinking, have to remind myself to breath, everything is on manual and if you are not used to manually controlling every little system in your body (who is) then stuff stops operating, plain and simple.

And like a computer a reboot (sleep) can be the fix.

Tremors are the same exact thing on a micro-scale; corrupted (and thus confusing to our appendages) messages can leave part or of all of the body shaking from lack of coherent direction. We have all seen the comical computers in the movies getting confused, shaking, smoking and finally burning up usually....if you have seen a hard drive try to run and it gets crappy and confusing directions, it looks exactly like the spindle arm has tremors!

So when I see things going wrong for others and I see/feel it happening to me, I can see whats going wrong; this has a ring of truth to my engineers soul and I have never had reason to doubt that inner voice. Totally neurological and when you look at it like a normal computer system, totally unsurprising as well. Obvious to the most casual observer as we used to say in the 60's thinking we were being so witty.

One more thing about situations like frozen stance: combating this stuff is hard and believe it or not physically demanding. For most situations that are screwed up and done-with, that's it. for scenarios like frozen stance that can go on for a time, we are not necessarily stuck the whole time...but rather there comes a point where we realize we can't will the limb(s) to move and continuing to try is wiping us out so we just internally go idle until either something about the situation changes or we are "reset" with sleep or something like that. We are not locked in that position for an hour; we are maybe trying for 5 minutes (to us) and the rest of the time we are, well, simply resting. Idling if you will.

You don't keep dancing on the gas pedal of a car with no petrol in it, why on earth would we keep trying over and over to do something that won't happen and seems to have no chance of happening? So getting stuck isn't great but its not like we are locked physically into something normally considered a torture position by most developed countries...its more like the message flow has stopped and we feel no more likely to restart it on our own than you might getting some peripheral to work again w/o rebooting.

From this engineers perspective, the single systemic cause of all this seems extremely obvious and I feel confident is stating that once the medical cause is isolated, who knows what could be improved in the lives of Parkinsons, LBD and patients with other similar disease conditions...

Jeff Cobb
Las Vegas NV