About synaptic pruning and why it occurs in the brain
The two biggest buzz words in neurology now are “neuroplasticity” and “synaptic pruning.”
Neuroplasticity is the idea that the brain is continually changing itself and adapting to learning, behavior, the environment and neural processes. A few decades ago, people believed that once the brain was formed, that was it. No changes could occur. Now we know that this way of thinking about the brain is incorrect.
Synaptic pruning is a process that occurs inside the brain that results in reducing the overall number of neurons and synapses. The first thought you might have is why would this be a good thing? Don’t we need every one of our neurons and synapses?
If you’ve ever been a gardener or taken care of your own bushes and trees, you already know that regular pruning or cutting and trimming them only helps their growth. After the pruning, there’s a new explosion of growth in the plant. If the plant is a fruit tree, the fruit will be larger than the year before and taste better. Clearly, in the plant world, the pruning is beneficial.
Pruning in the brain is also called axon pruning or neuronal pruning. When it occurs in the brain, it makes the synapses more efficient. Synaptic pruning is actually something that happens in all mammals, not just humans.
Your child’s brain was full of more than 100 billion neurons at birth. By the time he or she is an adult, that number will reach 500 billion neurons. Sooner or later some of these are going to have to be decreased in number. And what actually happens is that some neurons will be killed for various reasons, some of them due to environmental toxins and other reasons. This process is called apoptosis. This can be a good thing, as there’s no need for neurons that have been damaged.
Then the second way to decrease the number of neurons is by synaptic pruning. When this happens, the neuron is still alive but the axons and synapses that are no longer of any use are snipped off.
Synaptic pruning can be a good thing because some of the associations a child has for how the world works become more complex as he grows older. There’s no need to remember the old ones.
How does this relate to your child? If your child has auditory processing disorder that has been affecting his reading, his brain has already developed neural circuitry that isn’t serving him well. If these synapses and axons are pruned out of his brain and he’s been replacing them with new skills developed by using the Fast ForWord™ program, then the synapses and axons will soon be completely gone. It’s like giving your child a second chance at developing his brain. What could be better than that? Start building his cognitive functions so his brain can start pruning.
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