Toddlers' brains must be stimulated 'or they'll suffer learning difficulties'
Toddlers can be set back "decades" if their brains are not stimulated before they start school, experts claim.
The team of neuroscientists and charity workers called for more to be done to make the most of the "lightbulb" early years.
Toddlers' brains form new connections at double the rate of adults, a report from University College London's Institute of Child Health and the Save the Children charity pointed out.
Failure to develop adequate language skills can leave children struggling to learn in the classroom, said the authors of the 'Lighting Up Young Brains' report.
Last year, almost 130,000 children in England found themselves disadvantaged by poor language ability, they claimed. Professor Torsten Baldeweg, from the Institute of Child Health, said: "Why is it important to stimulate children before they go to school? It is precisely this period where we have explosive brain growth, where most of the connections in the brain are formed.
"We need input to maintain them for the rest of our lives. And we know that if these connections are not formed they, to variable degrees, will suffer longer-term consequences to their physical, cognitive but also emotional development.
"That's perhaps one of the most important lessons we've learned from these studies - that these early years are absolutely critical. Much more must be done to boost children's early learning."
Evidence showed that play-time can be made "brain-time" with a combination of talking, word games and singing, said the experts.
Such an approach stimulated early language and communication skills and provided the "building blocks" for learning.
Save the Children called on the British government to ensure that every toddlers' nursery had a qualified early years teacher to support both children and parents.
Gareth Jenkins, the charity's director of UK poverty, said: "Toddler's brains are like sponges, absorbing knowledge and making new connections faster than any other time in life. We've got to challenge the misconception that learning can wait for school, as, if a child starts their first day at school behind, they tend to stay behind."