This is actually the 3rd part in a series of articles that kicked off with Lucy Corradi writing a short piece titled – “Is Your Brain Healthy”? Which was followed up by “You can teach an old dog new tricks”. If you haven’t yet read that article, click the links and read those 2 articles before coming back to this one.
So why has this discovery of the plastic brain only recently come about?
400 years ago, Descartes declared that the mind (specifically the thoughts) belongs to the church and the body belongs to science. This lead to a workable, if uneasy truce between the scientists and the church. The scientists were able to get on with unlocking the secrets of material world and the church could still be responsible for our thoughts and ideas.
As the industrial revolution took place, science viewed our bodies like machines where the bits could be broken down and examined, with one bit doing this and another doing that. The brain was caught in between. The “thoughts” were not really considered to be part of the brain. Rather the brain was considered to be involved in regulating the body but had no role in free thought. At best the brain was considered as the junction point between thought and the body. Because the brain had no role in thoughts, it was considered a fixed unchanging organ and treated in a mechanistic way like the rest of the body.
The truth is that there have been scientists throughout the centuries who have argued that the brain must have some plastic properties. However until modern times, there have been no machines capable of actually measuring what is going on when the brain is at work. Thankfully there is now very solid research that proves that this “fixed” brain concept is totally wrong. We owe an awful lot to the clever boffins that invented the MRI machine – and not just for diagnosing brain tumours. These MRI machines allow us to see which parts of the brain light up during different activities.
The current view of the “regular” brain is that each section of the brain processes the information for which it is most suited – in other words, its all about which part of the brain can get the job done with maximum efficiency. The same goes for the pathways that connect different sections of the brain to one another. However if a section of the brain that usually processes information is damaged (or even missing), another pathway is created and a different section of the brain can find a way to carry out the same function!
In the first part of this article, we talked about a scene from the DVD, “The Brain That Changes Itself”. In this scene a blind man with a camera on his head and a sensor on his tongue was able to navigate his way around a maze taped on the ground and throw balls into a bin.
So how does a man who supposedly cannot see actually do this?
First we have to consider what the eyes actually do. The role of the eyes is to pick up signals from light hitting the retina at the back of the eyeball. That’s all the eye does, it doesn’t actually “see”. Messages are then sent from the eye to the occipital lobe. This is the section of the brain that processes what we see (it’s located at the back of the brain right in front of the knobbly bit that you can feel at the back of your head). The occipital lobe constructs an image from this information. So it’s the brain that actually “sees”, not the eyes.
So what happens with the blind man shown on the DVD with the tongue sensor in his mouth? The camera picks up an image and this is sent to the tongue sensor in the form of vibrations. Rather than information being sent by the usual route from the eye to the occipital lobe, the information is received directly by the tongue. A new connection is formed that gets the message from the part of the brain that processes what the tongue feels to the occipital lobe. An image is then created within the occipital lobe that allows the man to “see”. But it is not the camera that does the “seeing”, its not the tongue either, it’s still the occipital lobe, exactly the same as in a person with normal sight. The plastic brain has merely created an alternative pathway to get information about the light received by the camera to the occipital lobe. When I say “merely”, I am pushing the boundaries of understatement considerably!
It gets even more interesting. The occipital lobe is the part of the brain that is most suited to interpreting information and allowing us to build a vivid picture of what’s “out there”. However in the absence of visual stimuli – in blind or severely sight-impaired people, the occipital lobe doesn’t just sit around and do nothing. It gets recruited by other parts of the brain to assist with other functions. It’s well known that people who are sight impaired have a much better sense of touch. This is because their brains have far more neurones available for interpreting touch. More neurones gives the brain more available processing power. To an outside observer it appears that more information is being received from the fingers but that’s actually not the case – better discernment of that information is actually what takes place. This is the exact reason why Lucy is such a talented massage therapist. In this occupation, she has turned a relative “weakness” into a substantial “strength”.
Does all this make brain plasticity inherently “good”? Unfortunately no. So far I have painted a rosy picture. Brain plasticity does have a dark side. The one we see most often in clinic is the chronic pain syndrome.
In this case, there is tissue aggravation present but the brain over-reacts so that the perception of pain is far greater than the actual level of tissue injury. An example that is easy to understand is the repetitive strain injuries – commonly known as RSI.
At some earlier point in time, there was an actual tissue injury related to some activity performed regularly in daily life. Usually we associate repetitive strain injuries with occupational activities but really it can be anything at all. Usually rest from the activity and a little treatment will sort this out. However for some reason you can’t stop (or won’t where it’s related to recreational activities mostly revolving around golf it seems) the activity so the irritation never really goes away.
In this case your brain decides that it needs to be hyper-vigilant about preventing further injury so it produces a stronger and stronger pain message. Eventually this message will be out of proportion to the actual tissue irritation caused by the activity. What happens here is that the nervous system builds a stronger and more “efficient” system of circuits to provoke a pain reaction. The idea being that the pain reaction will prevent you from engaging in the activity or at least limit the time spent on it. This leads to further guarding by the body – most commonly in the form of soft tissue spasm.
It gets worse though because the hyper-vigilant system starts to look for other activities that also might cause a problem and associates a pain message with those activities too. So over time, the chronic pain patient is able to do less and less in their daily lives. Thus in this case, the plastic brain does not serve us well.
This is why we constantly focus on improved function when you visit us in clinic. You say “my shoulder still hurts” and we respond with “yes but look how much further your shoulder moves before the pain kicks in”. We don’t say this to be annoying (even if it is), rather we are trying to help you short circuit the chronic pain message that the plastic brain has produced.
The idea is that you replace the thought “this hurts, so its not getting better” with “I can do more, therefore it MUST be getting better”. This thought pattern engages the frontal lobe of the brain. When we engage our frontal lobe we are more able to objectively observe our “automatic” thoughts and actions. Being aware, combined with focussed attention allows us to change those thoughts and assists in short circuiting chronic pain impulses.
Prescriptive exercises also play a massive role in short circuiting chronic pain impulses as they further strengthen constructive mind and body connections. So there you have it, we don’t give you those annoying exercises solely for our own amusement!
Given that you have now learnt that your very thoughts alone can cause structural brain changes, it follows that changing the “self talk” related to our pain actually helps the pain go away. It doesn’t work over night but persistent effort does pay off.
A large part of this skill revolves around learning to turn off the stress response to increasingly busy lives with constant “sound bite” interruptions. This involves changing which part of the brain we are habitually using to make the daily decisions that drive our lives. However this is another topic in itself and I have probably given you enough to ponder for now.
by Rod Harris