March 29, 2024

The Brain Tells All: A Revealing Look at Brain Organization

Author: Kate Findley
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By Richard Restak, M.D., George Washington University School of Medicine and Health Sciences
Edited by Kate Findley, The Great Courses Daily

Just as our face and body can communicate quite a bit when we’re engrossed in our favorite activities, so can our brain! Richard Restak, Clinical Professor of Neurology at The George Washington University School of Medicine and Health Sciences chats with us about brain activity as it relates to musicians, athletes, and more. You’ll also learn about the link between mirror neurons and learning new skills.

Brain concept with man standing profile view with brain illuminated on dark background
The simulation hypothesis—the use of motor memory to interpret what other people are doing—activates mirror neurons, followed by learning new skills as brain memory begins. Photo by Pixel-Shot / Shutterstock

Brain Organization in Musicians and Athletes

No two brains are alike—not even the brains of identical twins. Using imaging, you can even make inferences about a person based on his or her brain organization.

A skilled pianist shows activation in the brain’s finger areas while listening to music or watching someone else perform music, but shows no response when watching random finger movements over a keyboard. 

A similar activation occurs in the relevant brain areas in ballet dancers and surgeons. You’ve often heard the phrase “muscle memory,” but a more accurate phrase for this phenomenon is “brain memory.”

Think of human brain development as existing on a continuum across the lifespan. Brains at all ages share the same challenges—the need for stimulation and the need to maintain nerve cell circuits despite a steady loss of neurons. 

The brain is unlike any other biological or mechanical structure. It undergoes a striking paradox, in which the brain experiences improved function while losing components.

Imagine having a car where, after six months, you pull the hood up and take a part out. Afterwards the car runs better, with better mileage, gas use, and so forth. That would be a very strange car, yet that’s how the brain works. 

Building Our Brain Circuitry

We receive our maximum numbers of brain cells when we are still in the womb, between three and six months before we are born. After birth and during our first two years of life, the number of neurons decreases while functional connections, or synapses, increase. 

This difference corresponds to changes in the ratio of grey matter to white matter. 

We refer to this decrease in neurons as pruning. If you’re into gardening, you know what this means: You go out and cut off branches that aren’t viable.

Circuits and networks, not nerve cell numbers, are the key to improved function. Learning is the means of establishing and maintaining these circuits. 

Think of brain circuits like friendships. Those that are maintained and enriched will endure; those that are neglected will disappear. Maintenance, novelty, and enriched experiences are like fertilizer on the brain, and they bring about growth and development.

Learning and Brain Organization

Learning new skills has been proven to affect our brain growth and activity. For example, if you’ve ever been to London and taken cabs, you’ve seen that the cab drivers really know the city.

You tell them where you want to go and they don’t have to consult anything: They take you right there. 

That’s not by accident. They’ve studied all the streets of London for two years and have taken a competitive test for cab driving. A study of these cab drivers shows that they have a larger hippocampus, with size related to years of driving experience. 

In another example, a study of older adults learning to juggle three balls over three months showed an increase in the volume of visual cortex, the hippocampus, and the nucleus accumbens. These changes disappeared three months after juggling stopped. 

Finally, a sighted person wearing a blindfold can learn the basics of using a cane, the way a blind person would, in just 10 minutes. That’s what’s called an enlargement of peripersonal space.

Notice the short time span involved: only 10 minutes. That awareness disappears only a few minutes after the blindfold is removed. 

We create new patterns of brain organization based on what we see, do, imagine, and learn. Learning something new establishes pathways consisting of millions of brain cells. 

Mirror Neurons and Brain Memory

However, doing—and not just observing—is what’s important. We have to activate the action-observation network. 

Going back to the example of ballet dancers, brain memory is based on the simulation hypothesis: the use of motor memory to interpret what other people are doing. Skilled athletes can watch and predict another athlete’s performance; boxers are particularly good at this. 

A skilled professional boxer can often see the punch coming before the person throwing it even knows what they’re going to do.

All of these examples are based on mirror neurons in the prefrontal cortex. These are a cluster of cells originally observed in the macaque monkey. 

The cells respond when one monkey watches another one grasp a peanut. These are the same cells that respond when the monkey grasps the peanut itself. 

Mirror neurons are task specific; they work according to a perception-action matching system.

“If you watch me reach for a cup of tea, your brain becomes active in the same areas that are used when I’m reaching for that cup of tea,” said Dr. Restak. “But if I reach for the tea cup for another reason or in another situation, such as cleaning up after a tea party, nothing happens. The mirror neurons are not activated.”

Therefore, brain organization is highly influenced by our experiences, and specifically by first observing and then carrying out the skills we wish to obtain.

This article was edited by Kate Findley, Writer for The Great Courses Daily.

Dr. Richard Restak is Clinical Professor of Neurology at The George Washington University School of Medicine and Health Sciences. He earned his M.D. from Georgetown University School of Medicine. Professor Restak also maintains an active private practice in neurology and neuropsychiatry in Washington, D.C.

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