July 1, 2005 Children who have speech-impairing strokes often learn to talk again, while adult stroke victims can lose their verbal abilities for good. By giving reading and verbal tests inside the MRI, researchers are comparing the inner workings of both children's and adults' brains that suffered from strokes, as well as of healthy subjects'. The researchers hope to develop therapies to help the adult patients talk again.
ST. LOUIS -- A baby has a stroke and can learn to talk. An adult suffers a stroke and may never be the same. What's the difference? Researchers are developing more effective treatments for stroke patients.
Ryan Timmerman has gone through many ups and downs. When Ryan was born he suffered a stroke. Evonne Timmerman, Ryan's mother, says, "In one minute your child goes from everything is perfect to it falls apart. It's hard."
In five short years, Ryan is almost completely recovered with absolutely no problems with his speech. Dr. Bradley Schlaggar says, "How they do it, how they recover, people don't know. If we get at that, we might be able to help other kids who don't recover so well, and maybe help adults as well."
Dr. Schlaggar, a pediatric neurologist from Washington University School of Medicine in St. Louis, Mo., is studying healthy child and adult brains and comparing their development to that of a stroke victim.
When you compare a healthy brain to a stroke brain, you can see the brain has re-wired itself and uses more areas to compensate for what was lost. How does it work? Dr. Schlaggar's team is using an fMRI machine to find out if exposure to visual or language cues encourages the brain to heal.
Dr. Schlaggar says, "We could come up with more specific rational interventions, treatments, that are really targeted at the exact problem at hand." And with the discoveries being made, things will continue to look up for stroke victims like Ryan.
Dr. Schlaggar hopes his research will help neurologists better treat their patients and come up with more specific and rational interventions that are targeted to the patient's exact problems.
Researchers at Washington University's School of Medicine in St. Louis have found that children activate different and more regions of their brains than adults when they perform word tasks. This may reflect the more efficient use of our brains as we mature. It may also shed insight on the brain function seen in children with Tourette's syndrome or cerebral palsy, among other conditions.
WHAT IS fMRI: Magnetic resonance imaging (MRI) uses radio waves and a strong magnetic field rather than X-rays to take clear and detailed pictures of internal organs and tissues. fMRI uses this technology to identify regions of the brain where blood vessels are expanding, chemical changes are taking place, or extra oxygen is being delivered. These are indications that a particular part of the brain is processing information and giving commands to the body. As a patient performs a particular task, the metabolism will increase in the brain area responsible for that task, changing the signal in the MRI image. So by performing specific tasks that correspond to different functions, scientists can locate the part of the brain that governs that function.
WHAT'S NEW: The fMRI scanner takes images for long periods of time, like leaving the shutter open on a camera. While it is easy to detect brain activity, however, it's difficult to tell how the brain reacts to specific stimuli. The Washington University researchers used an improved method known as "event-related" fMRI, in which the scanner takes a series of quick snapshots three seconds apart. This enabled them to tell which parts of the brain were activated as it was stimulated by the word-generation tasks.
HOW THE BRAIN RECOGNIZES WORDS: Even before a baby says his first word, his brain is sorting out the sounds and shapes of the words and sentences he sees around him. By the age of two, children already know quite a bit about sentence structure and basic grammar. Our ability to learn languages resides in a specific portion of the brain. The brain is hard-wired with connections, made by billions of neurons that send electrical signals to the brain when they are stimulated.
The American Association of Physicists in Medicine contributed to the information contained in the TV portion of this report.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.