WASHINGTON, D.C. — Parents should sing and talk to even the youngest infants, because the verbal stimulation is crucial to how well a child develops thinking and language skills later, a panel of experts said Thursday at the White House.

"At first glance, it may seem odd to hold a conference here at the White House devoted to talking about baby talk," First Lady Hillary Rodham Clinton said as she and President Clinton opened the one-day symposium on early childhood development. "But that discussion has never been more important."

Hillary Clinton said experts have confirmed what many parents have long felt - that "the song a father sings to his child in the morning, or a story that a mother reads to her child before bed help lay the foundation for a child's life, and in turn, for our nation's future."

The president added that new information confirming the effect of early upbringing was "absolutely stunning."

For the Clintons, two working parents, the research's emphasis on early nurturing by parents also raised a thorny question: Does science prove mothers are better off staying at home?

Hillary Clinton faced the question head-on with help from Dr. Deborah Phillips, a child-care expert with the National Research Council.

"Some people argue that what the research really tells us is that women with very young children should not work outside the home, period," the First Lady said.

Phillips reassured her there was no evidence that placing young children in good-quality child care impinges on the parent-child bond or stops babies from thriving.

A report by the New York based Families and Work Institute, which formed the core of Thursday's conference, found that during the first three years of life, the vast majority of the brain's synapses - or connections among brain cells - are formed.

How parents relate with children during that formative period directly affects emotional development, prospects for learning, and ability to handle stress as adults, the report said.

Brain research from the past 10 years was presented by a panel of experts, including renowned pediatrician T. Berry Brazelton, whom the Clintons engaged in lengthy discussions that were broadcast by satellite to nearly 100 locations around the country.

A survey of more than 1,000 parents was released at the conference; it indicated that many parents did not realize how much their babies were taking in. The poll conducted last month for the "Zero to Three" project of the national Center for Infants, Toddlers and Families, found that 73 percent said they did not believe a baby could communicate much until learning to speak a few words.

Speech specialist Patricia Kuhl of the University of Washington provided academic backing for holding your baby and cooing softly in gibberish. Babies respond to "mother-ese" and "parent-ese," whose melodic sounds actually provide a tutorial in the sounds that make up language.

"They are listening," she said.

The Clintons also put a political twist on the day, arguing for more spending on early education, child care and health care. The president, who successfully mined the family-values theme in last year's campaign, announced that the Pentagon, with a respected international day-care system, will share its expertise with the private sector; and the White House will host a similar conference on child care next fall.

Some children's advocates were still bristling Thursday from Clinton's signature on last year's welfare overhaul, which placed a five-year lifetime limit on benefits for families with children.

As Clinton nodded and scribbled notes, Brazelton bluntly told him, "In welfare reform, we turned the wrong way. We should have looked at what we were going to do with children before we pushed women out into the workplace."