BRIGHTON, England -- More nurturing mothers could lead to fewer stressed-out adults, or so suggests new studies on rats.

Scientists said they found that baby rats who were licked by their mothers a lot were less anxious and fearful as adults.

They also produced lower levels of stress hormones than those who were groomed less.

The researchers found that the mothers' licking caused the baby's brain to crank up a gene involved in soothing the body in stressful situations.

The research was led by Michael Meaney, a professor of medicine at McGill University in Montreal, Canada.

Several human studies have found an association between a mother's nurturing and the future mental health of her children.

But experts say it's unclear how the findings on rats translate to humans.

The studies on rats were presented Sunday at a conference in England.