Scientists at Nottingham University say rewarding children with attention-deficit disorders may work in the same way as medication.
Their study showed that the brains of these children respond to immediate rewards in the same way as they do to drugs.
The scientists measured children's brain activity as they played a computer game.
The kids were given extra points for less impulsive behaviour.
The study could mean children could take lower doses of drugs such as Ritalin.
However there is concern that parents and teachers could find it difficult to give instant rewards.
It is thought up to 5% of children in the UK have some sort of attention-deficit hyperactivity disorder (ADHD).
In severe cases they are often given drugs such as Ritalin, but it has also been found that reinforcing positive behaviour can help.
The Nottingham scientists wanted to look at the actual effects on the brain of this kind of behavioural therapy.
They found that giving children rewards helped them perform better at a computer game, although this did not work quite as well as the child's normal dose of Ritalin.
Brain scans showed that both the rewards and the drugs worked to normalise brain activity in the same areas.
Professor Chris Hollis, who led the research, told the BBC that a combination of drugs and incentives produced the best results.
He told the BBC: "Although medication and behaviour therapy appear to be two very different approaches of treating ADHD, our study suggests that both types of intervention may have much in common in terms of their effect on the brain.
"Both help normalise similar components of brain function and improve performance."
But he said there might be practical problems in giving children immediate rewards.
"We know that children with ADHD respond disproportionately less well to delayed rewards - this could mean that in the 'real world' of the classroom or home, the neural effects of behavioural approaches using reinforcement and rewards may be less effective," he told the BBC.