The Mozart. The mobiles. The foot toys with funny faces that jingle when the baby kicks. The Wiggle Worm gymnastics classes for 3- to 12-month-olds. Tiny tot music instruction in which moms earnestly shake maracas at babies who are drooling. No television before the age of 2.

The interacting. Always, always, the interacting. Even though it's sometimes fatiguing, even though you'd really rather be watching the Preview Channel--you must stimulate baby.

Now along comes "The Myth of the First Three Years" (Free Press, $25), in which it is explained to parents that they have been duped. (Politicians, likewise.) The myth, argues scholar John T. Bruer, is the idea that the first three years are the critical period for a child's development, that opportunities missed can never be recovered. For children to develop well, for better brains and secure attachments, they need stimulation and the right experiences. Science--new research on brain development--is used to back this up.

But there is no science to back it up, Bruer says. There is only oversimplification, misinterpretation and a lot of extrapolation. (Rat brains are not human brains, after all.)

"There is a huge gap between public understanding of what brain science says about the early years of life, and what the science really knows. And parents should know about that," Bruer said in an interview from St. Louis. He is president of the James S. McDonnell Foundation, and for 20 years has been involved in establishing research programs in psychology and neuroscience.

Many parents will recall the 1996 Newsweek cover story "Your Child's Brain." It told of neural connections and synapse formation. It had graphs showing when various critical periods for learning started and ended. (For your older kids, it was all over.)

That Newsweek article set off an avalanche of similar coverage. The researchers may have been reluctant to make claims of great discoveries, but that was not true of child advocates lobbying for money and legislation, or of reporters' coverage of the matter.

This led, Bruer writes, to governors wanting money to provide Mozart CDs to newborns and pediatrician T. Berry Brazelton writing a Boston Globe op-ed piece with the headline "To Curb Teenage Smoking, Nurture Children in Their Earliest Years."

It led to Rob Reiner's "I Am Your Child" campaign. And parents found themselves responsible not only for care and nurture, but also for baby's synapse formation.

Much of what has been said has no scientific basis, Bruer says, but went on to become "fact" anyway. Bruer has a message for policymakers: Don't make decisions based on what are considered facts about the new brain science. And he has a message for parents: Take it easy. For a child to develop poorly, there would be a neurological defect, or neglect, or abuse. For most children, that does not apply.

"What parents of normal children need to realize is that the normal environment children live in is well-suited for their robust and normal development," Bruer says.

Parents do not have to provide little kids with lessons in music, dance or sports for them to enjoy such things later on. (However, children really should begin learning foreign languages earlier than middle school.) And there is a lot of evidence people are capable of learning after age 3.

Bruer quotes Washington University neuroscientist Steve Petersen: "At a minimum, development really wants to happen. It takes very impoverished environments to interfere with development because the biological system has evolved so that the environment alone stimulates development.

"What does this mean? Don't raise your children in a closet, starve them or hit them in the head with a frying pan."

Can Bruer curb parental mania?

Maybe we can stop fretting about synapse formation and synapse pruning, but the mania was in place long before the 1996 Newsweek story. We've had Penelope Leach for some time now. Harvard's Burton White published "The First Three Years of Life" in 1975. They didn't recommend Wiggle Worms enrollment. But some of us, of course, got the idea from books that baby-raising is dead-serious business.

As Bruer notes, child-rearing advice has been the same for 50 years, new brain research or not. Parents are advised to pay attention to the baby, give sensitive care, read to the baby, talk to the baby and don't use poor day care.

That we knew already.