A baby learns to get the best care possible by smiling to please her mother or other caregiver. This is how babies learn to connect and communicate with other people.

The researchers say this ability to learn exists in a baby even before birth. They say newborn babies can recognize and understand sounds they heard while they were still developing inside their mothers.

Study: Baby, Sit Up and You'll Learn Better
Recently, an American study of 112 babies found they learned better when they were sitting up, not lying down. The babies appeared to learn better whether they were sitting up on their own, sitting in seats or helped to sit up.

Researchers with North Dakota State University and Texas A&M organized the study. The researchers say sitting up had what they called a "profound" and "significant" effect on the babies' ability to learn about objects. They say the body position may be linked to development in the brain.