Is intelligence changeable or not?

Until recently, it was a “fact” that you were born with a set level of intelligence and number of brain cells. But it has since been discovered that your brain has the capacity to change throughout your lifetime due to a property known as brain plasticity. The brain can continue to form new brain cells via a process known as neurogenesis.
Until recently, it was believed you were born with a set number of brain cells that could never be replaced. And that you came into this world with a set level of intelligence that never changed.
But it’s now known that your brain is a continual work in progress.
Due to a property known as brain plasticity (or neuroplasticity), your brain is constantly changing.
The discovery of this capacity of the brain to change has been heralded as the most important neuroscience breakthrough in 400 years.
Firstly it is better to answer this important question: what is Brain Plasticity?
Neuroplasticity is derived from two words: neuron (a nerve cell) and plastic (moldable).
Dr. Michael Merzenich, a leading pioneer in the science of neuroplasticity, defines brain plasticity as “the brain’s ability to change its anatomical, neurochemical, and functional performance status across the lifespan.”
In plain English, this means that your brain can change — forming new brain cells and neural connections and improving its capabilities — throughout your life.
Your brain continually alters its structure, function, circuitry and chemistry in response to everything you think and do.
And because your thoughts, environment, and life experiences are unique, brain plasticity is responsible for making your brain unlike any other.
This innate capacity to change has a profound impact on brain development when you’re young and plays a big role in how well your brain ages.
Unsurprisingly, the human brain is most malleable when you are young.
We come into this world with brains that are largely unformed.
The human brain, with its large cerebral cortex, is designed to build new neural pathways by learning from experience.
The first few years of life are a time of rapid brain development.
Then, as we approach adolescence, a lot of information deemed unimportant gets weeded out of the brain by a process known as synaptic pruning.
By the time we’re ten years old, our brains have pruned away 50% of the synapses we had when we were 2-year-olds. This may be why most of us have so few memories of our earliest years.
While the human brain is capable of change throughout life, once we reach adulthood, the rapid brain development of childhood slows down.
While the overall rate of change decreases, lifelong learning and new experiences continue to change both brain function and structure.
By developing new neural connections and allowing unimportant ones to wither, our brains continue to rewire themselves to adapt to a changing environment.
Unfortunately, as many adults grow older, the loss of brain cells and neural connections outpaces their formation, resulting in mental decline.
But it doesn’t have to be this way. Brain plasticity allows you to build new brain cells and create new neural connections at any age provided you keep learning and having new experiences and meet your brain’s basic requirements for staying healthy.
As result it is obvious that changing the functions of brain is possible due to recent scientific researches, and it means intelligence quotient can be interfered through proper psychological educations and by specific intelligence interfering systems we are able to help those people (especially children) who are suffering from Mental Retardation, learning disabilities or any other types of brain issues connected to brain functions.
Writer: Amin Hosseini Psychoanalyst

References:
1. Allison Gandey February 13, 2009
2. Medscape Medical News © 2009
3. Cite this article: Allison Gandey . AAPM 2009: Specialists Study Brain Plasticity and Its Transformative Potential - Medscape - Feb 13, 2009.
4. To Harness Neuroplasticity, Start with Enthusiasm JAN 31, 2012 By: Dr. Helena Popovic
5. Synaptic Pruning: Edalmarys Santos Department of Psychology Middle Tennessee State University Murfreesboro USA & Chad A. Noggle Department of Psychology SIU School of Medicine Springfield USA
6. Brain Plasticity: How learning changes your brain FEB 26, 2008 By: Dr. Pascale Michelon
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