Memory Test Suitable for Brain Injured Children

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Memory Test Suitable for Brain Injured Children
Library: MED
Keywords: HEAD TRAUMA BRAIN INJURY CHILDREN DIAGNOSIS TREATMENT MEMORY
Description: A relatively simple memory test can be used to track recovery of brain function in children with traumatic brain injuries, according to a study now available on-line. (Annals of Neurology, Apr-2002)



Embargoed until Monday, April 29, 2002

Contact: David Greenberg, dgreenbe@wiley.com, 212-850-6484

Traumatic Brain Injury

Memory Test Suitable for Brain Injured Children

In Combination With Brain Imaging, Test May Guide Research and Therapy

"In one ear and out the other." For parents, this refrain means that by the time a child reaches the kitchen, she will have forgotten that she went there to get a fork. For physicians, this fact of child development makes it difficult to assess the extent of brain injuries from blows to the head, subsequent recovery, or any potential therapies.

Researchers now report that a relatively simple memory test can be used to track recovery of brain function in children with traumatic brain injuries. The study is now available in the on-line Annals of Neurology, via Wiley InterScience Early View at http://www.interscience.wiley.com/annalsofneurology. Annals of Neurology is the research publication of the American Neurological Association.

"We show that brain-injured children can perform this test, suggesting that it could be used for diagnostic purposes, to study reorganization of function, or as an outcome measure for drug trials," said lead author Harvey S. Levin, M.D., a neuropsychologist at Baylor College of Medicine in Houston, Texas.

The test, which involves picking out letters that match or rhyme, is intended to assess the ability to remember and process information over a very short time-period or during a specific task. Such "working" memory is one of the brain functions that is typically impaired following severe blows to the head--in medical terminology, traumatic brain injury.

Working memory tests are useful in studying adults with brain damage, but the capacity for "working" memory clearly depends on the maturation of specific brain areas, meaning that the younger the child, the harder it is for them to remember and process the requirements of a task.

Levin's research group used a two-part test. In the first, a letter matching test, a letter flashes onto a computer screen for two seconds. If the next letter matches the identity of the first letter (e.g., "g" and "G"), the child should indicate a match.

To make the task progressively more difficult, in the subsequent rounds of testing, one, two, or three non-matching letters appear between the matching letters. The researchers count a successful match as a hit, but they also score a false alarm when the child mistakenly indicates a match. The second part of the tests requires the child to match letters that rhyme.

On the letter identity task, Levin and his colleagues found that the children with severe brain injuries scored significantly fewer hits than those with mild injuries or no injuries. As expected, older children did better than younger ones. There was no difference in the number of false alarms.

In the rhyme task, the severely brain-injured children did not have a problem detecting letters that rhyme, but they did generate significantly more false alarms.

The different outcomes between hits and false alarms on the two tests may relate to the fact that different brain regions process different aspects of a letter (e.g., identity and sound), and some of these regions are more vulnerable to damage in brain trauma than others.

"Our findings support the feasibility of using these tests, combined with MRI imaging, for evaluating patterns of brain activation as children use their working memory," said Levin.

Such combined testing could be used to assess both brain damage and recovery in brain trauma, as well the effectiveness of therapies to limit the damage and enhance recovery.

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