The brain is made up of billions of interconnected cells organized into structures such as the cerebrum, the cerebellum and the hypothalamus. These particular parts of the brain have long been known to control certain functions, and for many years scientists believed that these functions were set in early development and couldn't be changed. Recent research in neuroscience has changed this view.
Brains Adapt Naturally After a Traumatic Injury
Some of the first discoveries of neuroplasticity came from scientists investigating how brains recover after devastating injuries. Since the brain had been mapped out, with specific functions corresponding to specific areas, scientists were confused by patients who had an area of the brain destroyed yet could still perform the functions of that area.
For example, in one case, a patient who suffered a stroke that destroyed the left hemisphere of her brain, rendering her right hand paralyzed and making her unable to speak, later regained use of that hand and the ability to speak when the right side of her brain took over the functions normally assigned to the left hemisphere.
Using Stem Cells to Rewire the Brain
Another area of research is the use of stem cells to induce neural plasticity and repair parts of the brain that can't be fixed otherwise. Two different methods are using injections of cultured stem cells, and inducing existing brain cells to create their own stem cells that can work inside the central nervous system.
Some promising areas of research include injecting stem cells into damaged spinal cords, which might then grow into neurons that re-establish broken connections, and treating Parkinson's disease with stem cells, which could rewire the faulty neuronal connections that cause Parkinson's symptoms.
Brain Plasticity in Everyday Life
Neuroplasticity isn't only important for brains that have had a traumatic injury or illness. It actually operates at a lower level in everyday life. Whenever someone learns something new, the brain changes and adapts to this new skill or knowledge and may actually alter its structure. The effects of brain plasticity in learning seem to continue throughout life.
One of the most well-documented instances of brain plasticity in learning is structural change in the brain when someone learns to play a musical instrument. Even in training as short as two weeks, people learning music have visible differences in their auditory motor cortex, according to a 2008 study in the Journal of Neuroscience led by Dr. Claudia Lappe at the University of Münster. People who study music over many years, especially those who begin their studies before age 7, have been found to develop even more brain changes.
Neuroplasticity and Brain-Machine Interfaces
While connecting the brain to machines may seem like science fiction, since the discovery of brain plasticity it has actually been an active area of research.
Andrew Schwartz of the University of Pittsburgh School of Medicine has done research implanting electrodes into the brains of Macaque monkeys which allow them to control robotic arms using only their brains. The monkeys' brains adapted to these new "limbs" and the animals began using them to complete tasks, such as reaching for food with the robot arms.
In human applications, scientists have created brain-machine interfaces for blind patients which allow them to "see" for the first time. And researchers at Emory University were the first to use brain-machine interfaces to help a paralyzed man operate a computer directly using his brain.
Sources:
Lappe,Claudia, et al. Cortical Plasticity Induced by Short-Term Unimodal and Multimodal Musical Training. The Journal of Neuroscience, (September 24, 2008), 28(39):9632-9639
Neural Plasticity, Open Access Journal available from Hindawi Publishing Corporation
Andrew B. Schwartz, et al. Cortical control of a prosthetic arm for self-feeding. Nature, 453, 1098-1101 (19 June 2008)
Kennedy, P.R., Bakay R.A. (1998) Restoration of neural output from a paralyzed patient by a direct brain connection. Neuroreport. June 1;9(8):1707-11
 |
 |
 |
