Sometimes the numbing effect of TV can be helpful. Especially if you’re a child being stuck with a needle at the hospital.

Researchers confirmed the distracting power of television something parents have long known when they found that children watching cartoons suffered less pain from a hypodermic needle than kids not watching TV.

Especially disturbing to the author of the scientific study was that the cartoons were even more comforting than mum.

While it’s good to have a powerful distraction for children getting painful medical procedures, it is also troubling "because we have demonstrated the excessive power of television," said chief author, Carlo Bellieni, a father of three and a neonatologist and paediatrician at the University of Siena in Italy.

His research at a nearby hospital was reported this week in the British journal Archives of Disease in Childhood.

The study involved 69 children, aged from 7 to 12, who were separated into three groups and then asked to rate their pain on a numerical scale when they were stuck with needles used to take a blood sample. The children’s mothers also rated the kids’ pain.

Those watching TV cartoons reported half the pain as those who were being soothed by mum. When compared with children who just sat in a hospital room with mothers who didn’t try to soothe them, the TV watchers reported one-third the pain.

"The power of television is strong and it can be harmful for children if it is stronger than the force made by the mother to distract children," Bellieni said. "I believe that this power must be controlled and reduced."

In general, mum’s soothing touch may be overrated, another expert said.

Other studies have found that the mothers and fathers attempts at comforting often backfire because it makes the children feel that "something must really be bad" if they need to be soothed, said Dr Brenda McClain, director of paediatric pain management services at Yale University.

McClain, who was not part of the Italian study, said the effect may not be just because of television, but could be caused by any kind of distraction, such as storytelling. "Distraction is a very powerful tool," she said.

But it’s got to be passive distraction like television, not one requiring children to do anything because when they are asked to play, their reported pain levels go up, a study last year found, said Dr Stephen Hays, director of paediatric pain services at Vanderbilt Children’s Hospital.

Bellieni, who has noticed the distracting effect of television on his own kids, theorizes that being absorbed in television releases pain-reducing hormones in children.