card
329

brain plasticity

OLogy Series
biology
card
329

brain plasticity

OLogy Series
biology

Did you know your brain changes every day? The brain's ability to change is called plasticity. Every time you learn and experience new things, new connections form between neurons. And the more you do something, the stronger those connections become. The brain can also change if it's impaired or injured. It can "reorganize" itself, so healthy parts of the brain can take on new functions.

Flipping Experiment

Years ago, scientists created special goggles that flipped views upside down. Volunteers wore these goggles whenever they were awake.

At first, they were confused and dizzy because they saw everything upside-down. But after several days, something amazing happened. Even with the goggles, they started seeing things right-side-up. Their brains changed their mind's view!

Then the volunteers removed the glasses, but their brains had become used to the new view. Now they saw an upside-down world, even without the goggles. After just a few days, their brains once more adjusted and produced a right-side-up image.

Newborn babies can't see clearly at birth because:

their eyes are not fully developed

the seeing part of their brain is still developing

their pupils are still adjusting to light

Are you right?

Correct!

Each day, the network of brain cells in the visual cortex becomes more complex. As the baby looks out at the world, neurons send a flurry of messages between the eyes and the brain. As the brain matures, the connections between neurons become stronger and the baby's vision improves.

As you grow up, your brain continues to change. It develops slowest as a:

child

teenager

adult

Are you right?

Correct!

As we go through life, especially during childhood and the teenage years, we generate as many as 100 trillion connections! But unused connections weaken and fade away--a process called "pruning."

Your brain keeps changing as an adult. Everything you think, feel, and do:

changes the shape of your brain

makes your brain bigger

creates or strengthens connections between neurons

Are you right?

Correct!

With every experience (reading a book, playing baseball), signals race down pathways from neuron to neuron. When you remember or repeat the experience, these signals retrace those pathways and reinforce them. A new experience forms new connections.

Braille is a communication system for blind people. It uses a pattern of raised dots to represent letters and numbers. When studying:

they use the "vision" part of their brain to read words

the areas of the brain that control their fingers expand

both of these

Are you right?

Correct!

People rely on their sense of touch to read and write Braille. Their brain "reorganizes" itself so the part of their brain normally used for vision takes on the function of touch. They also rely on fine motor skills, so that area of the brain expands.

When stroke patients suffer brain damage, they might lose the ability to speak or move. But abilities that are lost can often come back.

Fact
or
Fiction
?

Fact

With intensive training, a person can often regain these abilities by forming new connections in healthy parts of the brain.

Definition: the brain's ability to change
Examples of Brain Plasticity: when neurons form in young babies; when new neural connections are made throughout life; when brain reorganizes itself to compensate for injury
Cool Fact: Experienced Braille users can read as fast with their fingers as you're reading these words with your eyes!

Image credits: man, © AMNH/E.Hamilton; icons, © istockphoto.com.