October 31, 2016

Brain Plasticity Will Blow Your Mind

New research on brain plasticity will blow your mind.  One amazing finding is that new stem cells are produced in the lateral ventricles of the adult brain (1).  What is even more amazing is how these stem cells migrate from the back of the brain to the olfactory bulb in the front of the brain (2).  Using time lapse imaging scientists have been able to watch stem cells latch onto a blood vessel highway and drag themselves to their destination.  First, brain chemicals push stem cells away from their birth place.  Additional chemicals stop the stem cells from getting off track along the way.  As the cells approach their destination more chemicals pull them in the right direction.  

Equally amazing is that new stem cells are produced in the hippocampus that is responsible for short-term memory (2).  Since learning is life-long, it is hard to believe that neuroscientists used to believe that remembering everything we learn can be crammed into the memory cells we were born with.  The adult brain grows thousands of new stem cells in the hippocampus every day (3).  Diffusion tensor imaging allowed scientists to see significant microstructure changes in the hippocampus after just two hours of training (4).

New technology confirms that nerve cells can sprout new branches.  For example, Marshall saw cortical regeneration for finger-thumb opposition (5).  A youtube video shows a neurite advancing towards other nerve cells and retreating.  New growth is called a neurite until it differentiates into an axon or a dentrite (6).  Researchers are still learning which chemicals support or hinder the neurogenesis seen in the video.  But they know that only repeated training makes new branches cluster together so they work efficiently as a group (7).  

I want to pull my hair out every time I hear someone say "The doctor told me there is a 6 month window for recovery after a stroke."

1. Carreira, B., Carvalho, C., & Araujo, I. (2012). Regulation of injury-induced neurogenesis by    
   nitric oxide. Stem Cell International, article ID 895659, 15 pages.
2. Bozoyan, L., Khlghatyan, J., & Saghatelyan, A.  (2012). Astrocytes control the development of    
    the migration-promoting vascular scaffold in the postnatal brain via VEGF signaling, J. Neurosci,
    32, 1687-1704.
3. http://www.ruor.uottowa.ca/fr/bitstream/handle/10393/23287/Ceizar_Maheen_2012_thesis
4. Sagi, Y., Tavor, I., Hofstetter, S, Tzur-Moryosef, S., Blumenfield-Katzir, T., & Assaf, Y. (2012).  
    Learning in the fast lane: New insights into neuroplasticity, Neuron, 73,(6), 1195-1203.
5. Marshall, R., Perera, G., Krakauer, J., Constantine, R., & DeLaPaz, R. (2000). Evolution of
    cortical activation during recovery from corticospinal tract infartion. Stroke, 31, 656-661.
6. Khodosevich, K, & Monyer, H. (2010). Signaling involved in neurite outgrowth of postnattally
    born subventricular zone neurons in vitro., BMC Neuroscience, 11(18), 11-18.
7. Jabr, F. (2012). Spine tuning: Finding physical evidence of how practice rewires the brain,
    Scientific American, April 16, 2 pages.

6 comments:

  1. You explain this so well Rebecca, it shouldn't take a genius to pull it all together and publish it as a stroke protocol. Dean

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  2. Good job, Rebecca. Yeah, I got that six month speech, but only in the timer it takes to recover was measured in years rather than months or weeks. I use you as an example to the doctors.

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  3. I was told five years for a recovery window. Thirteen years later I'm still noticing very small but steady improvements. I was quite young when I had my stroke (22), but even so...

    Very useful post. Thank you.

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  4. I couldn't agree more. I am getting so tired of meeting stroke survivors who tell me their doctors told them they are done recovering. I keep seeing new functional recovery from survivors who are five, ten, or even twenty years post stroke!
    Brian Glaister
    www.cadencebiomedical.com

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  5. I am glad to see continued research on this topic. I strongly believe in neuroplasticity. Without it, I would have been in a lot of trouble. I was having a small section of my brain taken out for epilepsy control when I had my stroke. Within a few hours, I lost two important sections of my brain. Ten years later, I still find myself making small, subtle improvements. Our brains our amazing with the repairs it can make to itself!

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  6. I realize I am reading this a year later, but I am an occupational therapy student and there is research out there that shows up 500+ repetitions is necessary to promote significant change in the brain... I will try to find the article and post it here!

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