LAZY parenting is resulting in children starting school developmentally disadvantaged because they watch too much TV instead of playing and being read to.

A neuro-psychologist in the UK, Sally Goddard Blythe, researched the link between children who missed out on simple childhood activities and those who started school with learning problems.

She found many toddlers were watching 4.5 hours of TV a day instead of playing, and went on to start school with poor emotional development and motor skills.

Dr Marc de Rosnay, an early childhood development expert from the University of Sydney's school of psychology, said children were put in front of a television screen too often.

"We are living in a world where there are lots of opportunities for a child to be engaged with no one for an extended time," he said. "There is some decent research that shows that motor skills develop when kids are out and about and experiencing the physical world ... as a nation (we now have) more children growing up with low levels of activity.

"There are government recommendations about how much TV kids should be watching, and it's not much."

While he stopped short of saying that parents who did not read to their children or interact with them were "neglectful", Dr de Rosnay said there were developmental consequences for children who missed out on that nurturing.

"It's fair to say that children who miss out on interacting with their parents, peers and siblings will find themselves at a disadvantage compared with children who have had that interaction," he said.

But he added that using play to develop a bond and trust between parents and child was more important than teaching a child to read at a young age.

"We live in a world now where children are meant to be numerate and have the first steps of letter recognition before they start kindergarten," he said. "We used to live in a world where kindergarten was the place that was done."

Dr de Rosnay said there was no evidence that if a child started school unable to read and write it would affect their long-term learning.

Ms Goddard Blythe found that almost half of all UK five-year-olds who started school only had the motor skills of a baby, including the inability to hold a pencil. The cause, she said, was because parents had not spent enough time playing with their children or letting them play with others.

Ms Goddard-Blythe also argued that when children missed out on being read fairy tales, it impacted on their ability to understand "moral behaviour" and how to deal with emotions.