Interesting quote from an article:

What does all this mean for parents? Does your research have any guidance for raising children?

One takeaway is that the billion-dollar industry of quote-unquote educational toys that are supposed to make your baby smarter is a boondoggle. There's no evidence that any of those things make a difference. Children are learning the way that other people's minds work, which is much more important to learn than even letters and numbers. I'm afraid the parenting advice to come out of developmental psychology is very boring: pay attention to your kids and love them.
That's good news, I think.

The article is here: Child Psychology: A New Look Inside Babies' Minds