The notion that young children can learn productively by watching television is widely dismissed by scientists who study the developing brain.
The time between the ages of 6 months and 3 years is accepted as a critical phase for learning skills such as language, and research suggests that this is best accomplished by interaction with adults.
A study by Patricia Kuhl, of the University of Washington, in Seattle, for example, has found that children aged 10 months learn sound patterns easily by playing with an adult, but learn nothing at all by watching the same adult performing the same games and exercises on a television screen.
snipSarah-Jayne Blakemore, of the Institute of Cognitive Neuroscience at University College London, said that the best evidence suggested television for toddlers was a waste of time. “There is a body of research showing that, in a variety of contexts, young children learn optimally with another human, rather than with a video of a human,” said Dr Blakemore, the co-author, with Professor Uta Frith, of The Learning Brain.
http://www.timesonline.co.uk/article/0,,3-2176928,00.html