Friday, July 24, 2015

Neuroscience in Focus - An Introduction to Neuroplasticity



Neuroscience in Focus:
An Introduction to Neuroplasticity




I cannot tell you what a dark and hopeless state I was in at the end of 2012 and I won't describe here the full extent of that state and why.

But I started the year of 2013 full of fresh hope in looking for answers to what would turn out to be the symptoms and resultant life changes of chronic traumatic encephalopathy and the several years of hell it/they had put me through. As regular readers know, I took up studying neuroscience and it was not long into that study that I came across the concept of neuroplasticity.

Probably because I was able to approach the study of the brain with such a "blank slate", and thus did not have to trouble myself with "unlearning" a lot of decades and centuries old outdated (and flat out wrong) notions that clog up the brains of so many older generation scientists and doctors (and, ahem, psychiatrists and psychologists), I immediately grasped the enormity of the possibilities for healing brains (and thus psychiatric disorders) using the principals of neuroplasticity.

I can honestly say that no other event in my long and eventful life gave me such a tectonic shift in life perspective than did the discovery of and grasping of neuroplasticity (okay, I'd better make it Number Two and put the birth of my daughter at Number One).

Even though it was discovered nearly forty years ago, the term neuroplasticity is still kind of a sexy new kid on the block term that's become quite trendy to throw around in the "brain biz" (especially by those flogging brain training games - though I introduce in this post my own very popular Brad's Brain Training Exercises that are more specifically designed for what us mental health peeps must work on). The problem is that few people really understand what it means and the full implications of what neuroplastic activity means in the brain and for human behaviour.

There are numerous aspects to neuroplasticity and how it works in the brain and what this means but I'm just going to introduce a few of the basics for our purposes today.

Very briefly for today, what it means to you and whatever condition you currently find yourself in is that however your brain is right now - and I don't care how "messed up" you think it is - it does NOT have to stay that way. Yes, your brain - and thus your habits, your reactions, your intelligence, your memory capacity and yes, your "zombie programs" - can be changed. The very wiring and programming of it can be changed. And thus YOU can change.

Everything I teach in this blog is based on this principle.

So what is it? Very, very basically and briefly for now it is:

Neuroplasticity is how your brain responds and changes to adapt to its (and your) environment, which is a great deal of what I was introducing in Genetics and Environmental Factors in Brain Development.

Neuroplasticity is how your brain responds to your own thoughts.

Neuroplasticity is how your brain learns new tasks.

Neuroplasticity is how your brain responds to catastrophic injury and heals itself (like a stroke in which entire brain regions will cease to exist because of full neuronal death due to oxygen starvation).

And neuroplasticity is the key to how you're going to change your brain and thus your behaviour(s), thoughts, responses, emotions and and many (if not all) of the symptoms related to whatever it is you may be suffering from. It is - or at least could be - the key to how you can change everything about your life (and no, this is not a feel good corny phrase to blow smoke up your ass and make you feel like you're dancing on sunshine (as we'll see as we go along)).

However, we're also going to see how the same principles of neuroplasticity are responsible for a good deal of the things you don't like about yourself. This is what some call the "the dark side of neuroplasticity" or maladaptive plasticity. I touch on this in many posts but will at some point get to a specific post on it.

Understanding the basics of neuroplasticity and how the brain adapts itself to conditions within you and around you is, I'll argue, one of the most important fundamentals in understanding human behaviour and most psychiatric and mood disorders.

It is the basis for both how we improve and learn and for how we "go downhill" when we experience mental health problems. Solidly establishing my argument is going to take far, far more than we can get to today so for now we're just going to have a very brief look at what the term means and what's going on in your brain. 


I have to state this absolutely unequivocally, there is absolutely nothing controversial about the principles of neuroplasticity, the hard evidence unquestionable. It is true that all its mechanisms may not be completely understood and it is also true that it many not work in the same way in two different people with similar cases but that the brain constantly undergoes changes that are "plastic" for a wide variety of reasons is beyond question. (1)

Okay, so lets have a little bit of a (very) basic look at how it works and why.

At its most fundamental level, it is really just basic cellular biology. All cells are capable of various structural and functional change in order to adapt to environmental conditions. This is literally how evolution works. This is how all life on earth works. So what brain researchers refer to as "neuroplasticity" is simply how cells in the brain and the connections between them - hence "neuro" - can change and adapt; hence "plasticity", which simply means to be "malleable" which simply means "changeable" in the same fundamental sense that all living cells can change and adapt.

Of course, as I fervently hope regular readers are beginning to understand, in the human brain this is a rather more complex process, to say the least. In fact, much recent research has found that human brains have mechanisms for neuroplastic change either not found in any other species or which function at higher and more important levels. It has been argued that these unique forms of neuroplastic change in the human brain are chiefly responsible for our soaring rate of evolution over the past several tens of thousands of years (no other species has ever evolved and adapted so rapidly as home sapiens).

All that ho-hum tedium aside, let's now take a better look at what all this means in our human noggins and what it means for you and turning your life around.

Firstly, back to some basic neuroanatomy. Remember Neuroanatomy 101? Okay, probably not (I'd suggest rereading it for the fun of it but it's okay if you don't).

First of all, you have in the neighbourhood of eighty-six billion of these:



Those are neurons and as we saw in Neuroanatomy 101, neurons "store stuff"; all the tiny little fragments of details of everything you are seeing, thinking, remembering, hearing, feeling and so on are stored in neurons. Now, those tiny little details in each neuron are of no use if a given neuron's particular set of details cannot pass its information off to neighbouring or task related neurons (to contribute to making bigger pictures, thoughts, words, images, ideas and all that stuff and getting it into broader networks). That happens through the axon (the longer branch you see coloured in yellow and sheathed in myelin and the axon terminals which are connected at neighbouring neurons' dendrites (those shorter spiky looking branches). The actual "hand off" of information happens in the synapses via a nifty little neurochemical transactions.

So our thoughts and various kinds of memories, being able to place names to faces, to be able to assemble pictures in our minds and countless so on are the results of billions of tiny packets of information in neurons being connected through wiring and synaptic connections working together in localized and brain wide networks to make up the bigger "pictures" or thoughts, ideas, concepts, etc.

Follow so far? So those synaptic connections between neighbouring neurons (and even far flung neurons, some of their axons are very long) are, to state the obvious, critical for all brain functions. And while the neurons are permanent (for the most part), the connections are not. The connections and dendrites can be and will be "pruned back" - or perhaps rebuilt and rearranged all throughout our lives depending on various internal and external experiences.




This is a very, very crude diagram but it serves well enough for us to get the basic idea. See that on the left? The more connections there are, the more networked communication there is between neurons, the fewer the connections there are, the less communication between neurons.

Now, obviously the one on the left is better and the one on the right worse, right?

No, not necessarily. It depends on what brain function we're talking about for that particular group of neurons. If that more densely connected group on the left happens to be in a region of your brain that's integral for "processing" math equations (which is not actually a single region, but a network of regions), then it's a good thing. If it happens to be in a region of your brain (again, as part of a network) creating really negative self-appraisal and really beating yourself up self-dialog, then it's decidedly not such a good thing.

Groups and networks of neurons all well interconnected might be responsible for a good memory, or it might be responsible for a bad memory. It might be responsible for a positive aspect of your life or an negative aspect. It might be for an area that helps regulate emotions or areas and networks for generating negative or inappropriate emotions. And much, much so on.

And see where it says "stimulated" and "unstimulated"? Neither of those are necessarily good or bad either. There can be "good" stimulation or "bad or unwanted" stimulation. And the stimulation can come from your external environment or from your own inner thoughts and perceptions.

And how these connections grow or prune back is based on one of the great fundamentals of neuroplasticity - "neurons that fire together, wire together". In other words, the more that particular group of neurons is "stimulated" - and thus stimulating neurons firing - the more they'll seek out those connected axons and dendrites and synaptic connections and "wire together". And again, this can be for good or bad. If it's a good skill we're learning (a new piano piece for example), that's a great thing. If it happens to be in parts of our fear or emotional pain circuitry that's going to create negative behaviours or reactions to life events, then it could well be a bad thing.

And just to remind you, at any one time in your brain you'll have as many as one hundred and fifty to two hundred trillion connections like that. And they are never, ever static. They are breaking down, reforming and "reaching out" all the time and can happen in split second time frames as you're thinking. Yes, a single thought can cause connections to re-organize themselves. This is really, really important to bear in mind.

Okay, that's at the "neighbour to neighbour" level of neuroplastic connection building.

As we saw in Neuroanatomy 101, we also have "long distance wiring" and a "wiring harnesses" that look like this:




These are "high traffic" and "long distance" axon bundles that carry major "communication" loads between major regions (the "connectome" that I first introduced in Neuroanatomy 101).

Many perform relatively mundane tasks like whisking data from your eyes to your various "image processing" centres in the brain (mostly at the back in the occitipital lobe) and all kinds of other boring tasks involved in getting your body and self through life. But a good deal of them are involved in our emotional responses and regulation, the connections that make up our higher human intelligence and all the really important stuff involved in making us human and in our behaviours in the world. These are the "trunk lines" that are chiefly of interest to us.

The "connectome" has been the subject of some breathtaking research in the past several years and some very exciting discoveries have been made. And some of these findings are strongly indicating that many of these "trunk lines" appear to be heavily implicated in all the major disorders from schizophrenia to major depressive disorder to ADD.

These major communication channels as well are subject to neuroplasticity albeit under somewhat different principles than what we saw with "local" wiring at the synaptic level. The major wiring can change and adapt as well but at a much slower pace, something referred to as axonal plasticity. When we hear some sort of behaviour or reaction is "hard wired" in, it is more in these major trunk lines that we are talking about. But that does not mean that certain key "highways" cannot be changed, it just means that there are different processes involved and longer time lines. 


However, the axons of the connectome are absolutely critical for the speed of communication between regions and just as importantly the timing and coordination of brain activity, both mental and physical. This is greatly regulated by the distinctive white "insulation" known as myelin (this is what gives "white matter" its name). Fantastic bodies of recent research, beautifully summarized here, shows that myelin is subject to neuroplastic change and excitingly, very rapid change in response to practice and training in which marked improvement the speed of mental and physical tasks can be noted.

Now, to further understand the implications and meaning of this to change who you are and all those reactions, emotions and habits you want to rid yourself of, we'll have to look more at brain regions and what they do and how they work together.

But for now I hope you have at least a bit of an idea of what neuroplasticity is and what's going on in that noggin of yours. There will be several other pieces in a series on neuroplasticity so we can learn better how to use this amazing brain function to heal our selves and our minds, but in time. 


(1) Added May, 2019. There are, I have found, legions of semi-educated "followers" of neuroscience who seem to take delight in disparaging the field and any claims made about our knowledge of the human brain. These are invariably people who, for reasons I won't speculate, enjoy being "critics" and "skeptics". While it is true that poor science (compounded by often atrociously bad science reporting) abounds and often outlandish claim are made, many of these people go beyond honest constructive criticism and healthy skepticism to denouncing anything that is known about the brain and how it functions.


Brief Overview of Sources:


I've many sources for my studies of neuroplasticity, but none more important than the book that introduced me to it, the literally life changing The Brain that Changes Itself.


The works and writings of neuroplasticity pioneer and expert Dr Jeffrey Schwartz.


And many posts by Yale University's Dr Jon Lieff such as this excellent primer on neuroplasticity. Dr Lieff's blog is considered one of the top sources for neuroscience on the Internet.

Plus the dozens and dozens of research papers I come across or am introduced to by one of my trusted personal sources.











9 comments:

  1. A very nice piece of work. You are certainly doing you homework and honing your skills.

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  2. I really wonder if your attempting the impossible, I have found myself becoming increasingly critical to the point of irritation at the quality of much of the output of neuroscience and I'm not alone. A search for neurotwaddle, neurobollocks, neurotrash, etc will point you to lots of highly critical reviews of the current state of neuroscience, some from neuroscientists themselves. Huge sums of money have been invested in researching the biological basis of human thoughts feelings and behaviour yet if you look at how much of this has lead to anything of use it should ring warning bells. Neuroplasticity is interesting, it is one of the ways in which the brain responds to its environment, and yes we see synapses being changes, but not everything happens at the synapses a nerve is covered with chemo-receptors and can interconnect with 10,000 others each one of these attempting to alter the nerves action potential. When it fires, that's all it does, they don't really operate as wires, each ones a switch the only information each nerve transmits is the fact its fired. Currently we don't even have a clear idea of all the chemicals that impact on nerve function even a single synapse may use several neurotransmitters and have a range of different types of receptors. I have yet to see any well reasoned attempt to try to convert the biology we are aware of into an understanding of though, feeling and behaviour. Clearly mind is a product of our biology but making sense of how this works is beyond us.
    I don't want to put you off, I'm actually interested in how you will approach this issue, I just hope you realise what your taking on and I don't think you'll get much help from neuroscience. Your a brave man/woman, I wouldn't attempt this but maybe this will be your opus, it would be a grand work indeed.

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  3. Well if nothing else Brad, you've got my interest and I will be following your discussions. I really wish you good luck with what I think is a very big project. Best wishes George

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  4. I found this helpful. Most discussions on nsuroplasticity I've read are more difficult to grasp. And I agree nsuroplasticity is the most important - and very doable- factor in healing. Not nearly as discussed in popular in media as chemical cures, yet much more effective and healthy in the long run. Thank you for sharing this information in a digestible way!

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    1. Thank you for reading and for your feedback, Lilac!

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    2. Err,*neuroplasticity I meant to say. I'd written that comment via phone.

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  5. The concept of neuroplasticity has been used in terms of strokes for a long time to provide hope and drive for the patient and practitioner. In Occupational Therapy we desire to develop normal movement and function by triggering responses from another part of the brain. Unfortunately insurances do not allow time for this to happen, and we begin to teach compensatory strategies. The speed of plasticity becomes a very important factor, as well as the skills and knowledge of the practitioner.

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    1. Yes, quite so. I am quite familiar with its principles being applied to stroke and other brain injury patients. It is a slow process requiring dedicated work and methods over time. As you point out, however, our myopic medical industry - and most people, frankly - cannot see or think in longer terms so such an elementary and essential principle in brain injury recovery is sadly overlooked by most.

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