It's a common problem among kids with ADHD to move around a lot, and frequently at that - hence, they are termed 'hyperactive'. Researchers at the University of Central Florida are attributing this unique feature to their inability to sustain concentration when handling the task at hand. Moving around helps ADHD-afflicted children to contiunously stay alert when completing challenging tasks that test their working memory.

"We've known for years that children with ADHD are more active than their peers. What we haven't known is why," said psychology Professor Mark D. Rapport.

"They use movement to keep themselves alert.

"They have a hard time sitting still unless they're in a highly stimulating environment where they don't need to use much working memory," he added.

During the study involving 8- to 12-year-old boys, those with and without ADHD sat relatively still while watching Star Wars and painting on a computer program.

While all of the children became more active when required to remember and manipulate computer-generated letters, numbers and shapes for a short time, kids with ADHD became significantly more active - moving their hands and feet and swivelling in their chairs.

The researchers suggest that parents and educators can use a variety of available methods and strategies to minimize working memory failures.