Making temporary changes to brain could speed up learning, study reports

In a breakthrough that may aid treatment of learning impairments, strokes, tinnitus and chronic pain, UT Dallas researchers have found that brain nerve stimulation accelerates learning in laboratory tests.

Another major finding of the study, published in the April 14 issue of Neuron, involves the positive changes detected after stimulation and learning were complete. Researchers monitoring in rats found that eventually returned to their pre-stimulation state, but the animals could still perform the learned task. These findings have allowed researchers to better understand how the brain learns and encodes new skills.

Previous studies showed that people and animals that practice a task experience major changes in their brains. Learning to read Braille with a single finger leads to increased brain responses to the trained digit. Learning to discriminate among a set of tones leads to increased brain responses to the trained tones.

But it was not clear whether these changes are just coincidence or whether they truly help with learning. The current research demonstrates that changes in the brain are meaningful and not merely coincidental, said Dr. Amanda Reed, who wrote the article with colleagues from The University of Texas at Dallas' School of Behavioral and Brain Sciences.

Reed and her fellow researchers used to release neurotransmitters that caused the brain to increase its response to a small set of tones. The team found that this increase allowed rats to learn to perform a task using these tones more quickly than animals that had not received stimulation. This finding provides the first direct evidence that a larger brain response can aid learning.

Future treatments that enhance large changes in the brain may also assist with recovery from stroke or learning disabilities. In addition, some such as or occur when large-scale brain changes are unable to reverse. So this new understanding of how the brain learns may lead to better treatments for these conditions.

Researchers examined the laboratory animals' brains again after the rats had practiced their learned task for a few weeks. The brains appeared to have returned to normal, even though the animals had not forgotten how to perform the task they had learned. This means that, although large changes in the brain were helpful for initial learning, those changes did not have to be permanent, Reed wrote.

"We think that this process of expanding the brain responses during learning and then contracting them back down after learning is complete may help animals and people to be able to perform many different tasks with a high level of skill," Reed said. "So for example, this may explain why people can learn a new skill like painting or playing the piano without sacrificing their ability to tie their shoes or type on a computer."

The study by Reed and colleagues supports a theory that large-scale brain changes are not directly responsible for learning, but accelerate learning by creating an expanded pool of from which the brain can select the most efficient, small "network" to accomplish the new skill.

This new view of the brain can be compared to an economy or an ecosystem, rather than a computer, Reed said. Computer networks are designed by engineers and operate using a finite set of rules and solutions to solve problems. The brain, like other natural systems, works by trial and error.

The first step of learning is to create a large set of diverse neurons that are activated by doing the new skill. The second step is to identify a small subset of neurons that can accomplish the necessary computation and return the rest of the neurons to their previous state, so they can be used to learn the next new skill.

By the end of a long period of training, skilled performance is accomplished by small numbers of specialized neurons not by large-scale reorganization of the brain. This research helps explain how brains can learn new skills without interfering with earlier .

The researchers used anesthesia when inserting electrodes into the laboratory rats' brains. The brain stimulation was painless for the rats, Reed said. Co-authors of the study were Drs. Jonathan Riley, Ryan Carraway, Andres Carrasco, Claudia Perez, Vikram Jakkamsetti and Michael Kilgard of UT Dallas.

Related Stories

New adult brain cells may be central to lifelong learning

May 23, 2007

The steady formation of new brain cells in adults may represent more than merely a patching up of aging brains, a new study has shown. The new adult brain cells may serve to give the adult brain the same kind of learning ...

Learning causes structural changes in affected neurons

Feb 03, 2011

When a laboratory rat learns how to reach for and grab a food pellet – a pretty complex and unnatural act for a rodent – the acquired knowledge significantly alters the structure of the specific brain cells involved, ...

Why you remember names and ski slopes

Nov 21, 2007

When you meet your boss's husband, Harvey, at the office holiday party, then bump into him an hour later over the onion dip, will you remember his name? Yes, thanks to a nifty protein in your brain called kalirin-7.

Recommended for you

Study links enzyme to autistic behaviors

10 hours ago

Fragile X syndrome (FXS) is a genetic disorder that causes obsessive-compulsive and repetitive behaviors, and other behaviors on the autistic spectrum, as well as cognitive deficits. It is the most common ...

A new cause of mental disease?

16 hours ago

Astrocytes, the cells that make the background of the brain and support neurons, might be behind mental disorders such as depression and schizophrenia, according to new research by a Portuguese team from ...

Molecular basis of age-related memory loss explained

Jul 22, 2014

From telephone numbers to foreign vocabulary, our brains hold a seemingly endless supply of information. However, as we are getting older, our ability to learn and remember new things declines. A team of ...

The neurochemistry of addiction

Jul 22, 2014

We've all heard the term "addictive personality," and many of us know individuals who are consistently more likely to take the extra drink or pill that puts them over the edge. But the specific balance of ...

User comments