In what is believed to be the first real evidence to support what is becoming a growing field of inquiry, the use of special computer games to "train" their brains improved the ability of healthy children to pay attention during scientific trials, researchers reported Sept. 26.

Their research has important implications for schools, which are charged with educating an increasing number of students with attention disorders.

It's not clear just how much the games helped, other specialists cautioned. But with booming interest in developing therapies for attention problems, the research sheds light on how a normal youngster's brain pays attention in the first place.

At issue is "executive attention," the ability to tune out distractions and pay attention only to useful information.

The capacity develops between the ages of 3 and 7, said University of Oregon psychologist Michael Posner, who has studied cognitive development by measuring electrical signals from the brains of preschoolers and young children.

There's great individual variation among healthy children and adults, and problems with this particular attention-paying neural network might be one of many factors involved in attention deficit hyperactivity disorder, or ADHD.

Posner and colleagues at Cornell University's Weill Medical College wondered if it's possible to speed this network's normal development.

They adapted computer exercises used to train monkeys for space travel into games for 4- and 6-year-olds: For five days, the youngsters progressed from a game that moved a cat in and out of grass to more complex tasks, such as choosing the largest number amid deliberate distractions.

The researchers measured the children's brain activity with electroencephalographs and administered tests of attention and intelligence before and after the training; some children also underwent genetic testing.

The brains of the 6-year-olds showed significant changes after the computer training compared with untrained playmates who watched videos, Posner reported Sept. 28 in the journal Proceedings of the National Academy of Sciences.

They were small improvements compared with the effect that simply getting older brings, Posner cautioned.

The 4-year-olds showed little change.

There also was a genetic effect: Children who were less outgoing and more controlled were better able to concentrate for their age and thus showed less effect from the training.

The study "significantly advances our understanding ... because it demonstrates that executive attention skills can be trained, or development accelerated, in young children," neuroscientists Karla Holmbie and Mark Johnson of the University of London's Centre for Brain & Cognitive Development wrote in an accompanying review.