Whaaat? It was largely accepted until fairly recently that the human adult brain, was essentially fixed. This was illustrated in full color diagrams confidently mapping the regions and structures responsible for say moving the left pinkie or for processing the feelings of biting the tongue. Ouch! It was believed that every bit of neural real estate was zoned and assigned a specific function. So, it had to be true, right?
Wrong! Much research in recent decades has proven this to just not be the case. Many scientific studies have confirmed that the brain is plastic meaning it is not fixed, not static, and not hard wired. It is malleable, dynamic and capable of physical change all throughout adulthood.
I like to think of our brain like play dough. We are holding this blob in our hands and can shape it however we choose. We sculpt our brain with our environment, our experiences, the demands we place on it repeatedly, and, basically, the lives we lead every day. Works both ways - good and bad.
Plasticity was demonstrated early on in an experiment with ferrets, who have identical wiring to the auditory cortex and visual cortex as humans except for one important factor, the timing. Human basic wiring exists at birth. Ferrets grow this circuit after birth. Scientist interrupted this pathway in the ferrets with some very careful brain surgery so that nerves from the eye grew into the auditory cortex. The ferrets were then trained to respond to sounds and lights. The ferrets "heard" the lights with parts of the brain that would normally process sound.
In a later experiment, sighted adults were blindfolded all day, every day for 5 days. They spent their time learning Braille and performing various tactile and auditory activities. Their brains were scanned before and at the end of the experiment. Beforehand, their auditory cortex showed normal activity upon hearing sound. Their visual cortex lit up when seeing as expected, and their somatosensory cortex buzzed appropriately when fingering Braille symbols.
After just 5 days of being blind folded, their "visual" cortex became active when doing all these things. The "seeing" brain was now hearing and feeling. Even though it had spent all its years up until that point handling visual input, with no signals coming from the eyes at all, the brain reorganized itself to utilize the newly dormant areas for other functions - sort of like an industrious developer seizing some prime vacant piece of land and capitalizing on it.
This same amazing ability is the cause of phantom limb. People who have lost a limb experience a brain reorganization. The part of the brain that formerly received input from the missing limb is taken over by neighbors on the homunculus. Because the face and the hand are side by side, it has been documented that someone missing a hand actually learned where to scratch on their face to satisfy an itch on the missing hand.
Phantom pain has been shown to be caused in most cases by that being the last signal the brain received from the lost limb. In a confused loop, the brain processes this sensation endlessly. This phenomenon has miraculously been alleviated by utilizing neuroplasticity and tricking the brain and interrupting this cycle with mirrors which visually replace the lost limb and change the signals to the brain.
There is a catch to neuroplasticity. It only occurs when a person is paying attention and focusing on the input whether it be intentional or not. Hence with directed consciousness, a person has the ability to change their brain. Unfortunately, this is more often done unconsciously by most people.
The science of neuroplasticity is very new. It's limits are unknown. It opens up a world of possibilities. In a very personal sense, each individual has the power to change their life. On a broader scale, the same brains that now practice prejudice, hatred and warfare have the potential to be kinder, more compassionate and less aggressive. It can happen one brain at a time.
Saturday, April 24, 2010
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Debbie,
ReplyDeleteI find this so fascinating - really to think about how quickly our brains can change. And the idea of our brains as play-dough...I love that! To me, this really does say that we have the ability to form our brain...and that IS pretty awesome news!
testing, 1..2..3..
ReplyDeleteI just wish my stubborn hard-headed attitude could change as well as my brain :)
The old adage, "use it or lose it", is so true. If we stop focusing on something harmful or negative, the neurons and synapses die in time and we can create new connections. And all we have to do is learn how to connect the brain to the heart and we change everything in what feels instantly. As people obeserve us in our "new" heart, they are changed. That's why we only have to become the change that we want the world to be without trying to change it. Yea for neuroplasticity!!!
ReplyDeletePenn, your attitude CAN change. You can change whatever you decide to do so. You have to consciously make the decision to do so, affirm it often and recognize and challenge the thoughts or behaviors that are contrary to how you want to be -the old pattern, then transition to the thought/behaviors you wish to live and implement...with regularity this WILL change your brain and become the default for you. It is within your power. Your brain, in particular, is magnificent and so powerful. Put it to work FOR you! Luv ya!
ReplyDeleteTony, you are so right. We can lose the things we don't want by not using them and focusing on them. Voila! Kinda neato! Nature has equipped us all with a magical power to not only change ourselves, but the world as a whole. As witnessed by humanity,it is much easier said than done, but we can do it starting with ourselves.
Lance, can't forget you! Thanks for the kind words. Yes, our brains give us a truly remarkable ability here. The trick is to get people to use it!
ReplyDeleteDebbie,
ReplyDeleteI read Dr. Doidge's book last year but just yesterday came across this talk he gave in Melbourne. I don't know if you've seen it, but I'll put in the link. Plasticity is revolutionary, and not just inspiring for anyone who has suffered brain injury, but for the possibilities of human intelligence itself:
http://www.youtube.com/watch?v=tFbm3jL7CDI
Tim
Thanks for sharing that amazing video clip. I think I have seen it before, but good to see again. He is my hero. So great. Makes me feel like anything is possible. Neuropasticity is so empowering, I think, because it tells us definitively that we can really effect anything we want to by changing our own brain. It is a super power we all have. We just have to start using it! I am and I am loving it. Hope you are putting it to good use in your own life. Now, for the rest of humanity...we can just keep spreading the word.
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