Tuesday, October 4, 2011

Fearfully Made . . . Celebrating the Gift of Terror Part VI

THE ANXIOUS BRAIN

I wanted to create a post that clearly explained how the brain creates the feelings of anxiety and panic.  However, I can not do the job justice in a simple posting.  I've spent the majority of my 30 year career in neurology and I think I understand the brain much better than most people. However, the complexities of the brain, especially when it comes to things like anxiety, are far too much even for me to understand, not to mention trying put it in laymen's terms here.  Part of the problem too is that even the scientists, who study such things, know only about 25% of the story.  So I will cover some basics.

First of all, I must continue my philosophical argument from last time that the brain is real, its circuits and chemistry determine how we think and how we feel.  This would sound like a no-brainer (pun intended) however, Christians, and in some ways the general public, don't really believe that.  They see the head as an empty tank holding this vapor (as Plato would see it) which we might call the soul.  The soul isn't based in electrical circuitry or chemistry, but purely on moral choices.

But the brain is real, physical and created by God as a masterpiece. Like I said last time, by the influence of the fall (and an atheists would say from genetic mutations) the brain isn't perfect but has flaws. The flaws can be in perception, processing and in emotional response.  There are two levels of perception, the physical and the cognitive.  The physical is made up of the senses; vision, hearing, touch and etc. The cognitive perceptions is how our brain interprets the physical perceptions or incoming data.  I honestly believe that most mental illness occurs in the cognitive perceptions of the incoming physical perceptions. A paranoid schizophrenic would see your eyes glancing somewhere else while they are talking to you as a deliberate insult in exactly the same way as if you had slapped them and walked away.  They mis-interpret reality in a way that can be so off that eventually they can loose all touch with reality.

So the way that God created the brain to work, when it comes to anxiety, is that we see, hear, touch and that information comes into the brain. The fundamental processing of that raw data occurs in the parts of the brain, which are responsible for the senses such as the occipital lobes process vision in-put.

That sensory input is then sent to the cognitive processing areas (for example the frontal lobe)  where the data is interpreted. Next, that re-packaged data is then reacted to via emotion, autonomic nervous system and integrated with memory. I know, all basic stuff.

I will add one more caveat.  The brain does have similarities to a computer but it is not identical.  For one, the brain is many times more complex than a supercomputer. They both use memory (the brain many times more) but there is a difference in how this memory is stored. In the brain, memory is store in a dynamic process of living tissue.  Neurons actually grow dendrites and axons to create bridges of memory in the brain while a computer (form what I know) it is a static process of electrical charge, huge numbers of 1s an 0s. The charge is present or not. I won't even mention quantum memory because that is totally different.

So if the brain's memory is biological and dynamic, what does that mean?  It means that the structure of a brain can change based on incoming data.  A computer's structure does not change.  I will come back to this when we talk about anxiety. The brain, like a PC, comes pre-loaded (at birth) with software.  But that software is fluid and will change with input.

Now back to anxiety.  So when data comes into the brain via the senses, then it is processed in the cognitive part and interpreted, it is sent to the proper part of the brain.  One complex system is the emotional one often represented by the limbic system. The Limbic System includes more familiar names of brain structure such as the thalamus, hypothalamus, hippocampus and amygala. These are responsible for how you feel on a very visceral and even subconsciousness level.

So if the cognitive part of the brain perceives the incoming data as threatening, it will send the signal to the limbic system in a way to initiate a fear response. Then fear or anxiety is preceived as an emotion. If that emotion is great enough, then the next step, the hypothalamus releases chemicals that go to the pituitary gland. The pituitary gland in response releases chemicals which tell the adrenal glands to release epinephrine and cortisol.  This part of the system is what gives us superman type powers to either go catatonic, to put up a big fight or to run like the devil.

So, in the case of a lion approaching you, the senses bring into the brain that information.  The brain then cognitively processes the data and determines the threat level (think Homeland Security here).  If the lion rushes towards you, the brain kicks it to the next level.  The fear becomes acute. The hypothalamus-pituitary-adrenal glands (it is called the "axis") kicks in. The epinephrine (also know in laymen's terms as adrenalin).  When epinephrine enters the blood stream, it is like a bucket full of keys looking for the right locks. The locks are scattered throughout the body, in the airways, blood vessels, heart, eyes, skin, muscles and etc.  When the epinephrine keys hit those locks they do things such as; dilate blood vessels to the muscles and lungs and constrict those in the digestive tract, they cause the airways to dilate to allow in more oxygen, they open the pupils so you can see better and they make the muscles more jumpy and ready to act.  So all of these things turns you into a type of "Incredible Hulk" where you are transformed into a super version of yourself.  When this happens and you are in front of a crowd speaking, or like B on a school bus, it is called a "panic attack."

So nothing I've said should amaze anyone as they've heard this since middle school biology.  But you can see the gift of this system.  God designed it to keep us safe.  The anxiety causes us to avoid the places where the lion sleeps. The ramped up systems allows us to either fall down and play possum, fight back or run for escape. It is truly a wonderful gift.

But I want to next talk about how errors in different parts of this system causes us to suffer from over anxiety or panic attacks. I want to look deeply at why these things happen, why it is a good thing and why the sufferer should not be ashamed.  Those Christians who have never suffered from anxiety love to use the lack of anxiety as proof of someone's faith or spirituality.  It puffs them up. But Satan's work in this world is to accuse, tell you that you are unclean.  That's how he ruins our lives.

More later.  Is anyone still out there?  Should I continue?







3 comments:

Anonymous said...

yep - we're out here...continue

Anonymous said...

ditto!

Anna A said...

Please continue, and I'm glad that you are talking about the basic stuff. If I ever learned it, it was in the Dark Ages, and long forgotten.