What's happening in the brain?
 

I'm wondering what is (or isn't) happening in the brain that causes it not to heal.

Example: A person had an accident a year ago. There's obviously physical damage to the brain. Then for a week he overdoes it. This causes a setback. Is the setback a result of chemical damage in the brain or what? I get the physical trauma causing symptoms.

I've heard that excessive stress kills the brain. Is this kind of what is happening in the brain during a setback? Is there too much stimulus that it causes stress chemicals to flood the brain?

Thanks!

That's a good question...I wonder the mechanics of setbacks as well.

Bud

Yes, it is a cascade of bad chemistry that messes up the brain. The physical damage makes the brain less able to properly metabolize energy and use nutrients to make neurotransmitters and such. The waste flushing system called the glymph system, similar to the lymph system in the rest of the body, is extremely delicate. It is so fine that it was not even discovered until a few years ago. This clogged or damaged glymph system may be why DTI MRI's can recognize abnormal flows of fluid in the white matter in areas affected by injury.

https://www.urmc.rochester.edu/news/...-in-brain.aspx

Is it known how definitively DTI can show damage from mTBI? That is, if you've had a concussion that results in brain damage, would DTI always pick it up? I guess I'm asking because this seems like a possible way to distinguish between PCS that's primarily anxiety driven, and PCS that's from damage in the brain resulting in abnormal drainage, axonal shearing, etc.

A DTI MRI will not differentiate between anxiety driven symptoms and physiological driven symptoms. It just shows the brain is struggling to work properly.

A DTI does not show damage. It is like seeing an ink spot on the driveway. It shows that there is a oil leak but does not show where that oil leak is and what caused it. It can give a general location but no specific location. Keep in mind that an MRI can only see clusters of 10,000 neurons at a time.

If anxiety exists, it should be resolved. Once it is resolved, then, you can determine if there are residual PCS symptoms. For some, their anxiety is never resolved fully so they have to learn to live with the conglomeration of physical and psychological symptoms.

It can be like working in the rain. If you are constantly annoyed by the rain, it will interrupt your work. But, use work-arounds (rain coat, etc) and one can continue to work even though it is raining. You may still be getting wet (hands, face).

An even better rain analogy is Hawaii. The locals can easily recognize the tourists. When it rains unexpectedly, they react and run for cover. The locals know the rain is usually short lived and don't even break a stride. They know that it will likely stop soon and their clothes will dry off.

The second analogy is primarily how I live my life. I can perform at a high level besides the many deep potholes in my functional abilities. I just step around them. Sometimes, I get frustrated in the short term but I can usually take a breath, step back and start again. Restarts are much better/easier than trying to fix the failure.

From what I've read so far, brain metabolism of glucose is altered, blood flow is reduced the first four weeks or so, and damage need not show up on imaging, except DTI can pick up axonal/dendritic damage that's too small to show up on other imaging. I've got a lot of links put away but it might take a while to find stuff.

I'm baffled by the kinds of setbacks, including my own, often reported, where things seem to work fine for a while then out of nowhere symptoms return.

Presumably the neural processes that break down from anxiety and that break down from physiological damage are different, and that difference at least might, in principle, show up in a DTI. That's just my intuition, could be totally wrong. I guess I'm just generally curious whether, if you took everyone on neurotalk for example and gave them a DTI, if it would indicate damage for everyone. Part of me thinks that this could be a more definitive test of the actual level of brain dysfunction, and that could provide information that might relieve anxiety about damage.

I like the Hawaii analogy, but speaking from having done quite a bit of field work in Hawaii, in some places the rain rarely lets up. The same might be said for some PCS brains.

If you are watching fluid flow down a sewer and you cannot see color, you'll never know if the flow is grey water (wash water) or yellow water (pee). A DTI just sees abnormal flow of water, not the content of the water flowing. The water flowing through the white matter could be from damage to the axons and neurons or from stress related chemical imbalances. But, the research suggests that a physiological cause is the greatest likelihood, at least that is the focus of the research.

Current DTI MRI resolution is 2 to 2.5 mm. Research DTI MRI's using higher Tesla fields can image at 1 mm resolution. 1 mm is still not fine enough to define axon and dendrite damage. That requires very expensive and rare 6-7 or even 11 Tesla MRI's. They are reserved for research. An 11.7 Tesla MRI is being build at a cost of 200 million dollars. Normal clinical use 1.25 to 3 T MRI's cost $350,000 to a million dollars. Highly utilized high field research MRI's cost $100 per hour just for operating costs, electricity, helium, etc.

If we compared an MRI image of axonal fiber bundles to a bundle of electrical wires, it can see bundles of 10,000 down to 1000 wires as one bundle but not individual wires. There would be variations in intensity but not finer imaging.

A look at an MRI/MRA or MRI w/ contrast in 3D shows what is imageable. The smallest image is larger than a piece of spaghetti. Anything smaller is an indistinguishable haze that they filter out.

I tend toward the physical damage theory too. I notice much of my emotions remind me of when I was a child; I've suddenly lost the ability to discipline myself, possibly my amygdala. That's years and years of learning. . I read in a recent book ('15) The Traumatized Brain by two Johns Hopkins MDs offering a straightforward explantion. Your frontal lobe feeds back into your lower (limbic:emotional) brain. I was hit on my right frontal lobe (possibly a portion called the dorsolateral cortex.) This kind of damage is very common and can result in personality change.

I don't think it's practical to try to image on the cellular level. But macro MRI (fMRI?) studies have yielded a growing body of knowledge (visualizing blood flow, I think) on how different areas of our brains get involved with various activities. I'll bet you my dynamic MRIs would be different from what I had before and likely would show an over-active amygdala.