At birth babies' brains have 100 billion neurons -- as many as they will ever have. As a baby grows, so do these neurons, forming branches that connect with other neurons to transmit signals and share information. Compared to most other animals, humans have a huge number of brain cells. "It's as if nature decided, 'We want these guys to have enormous brains, but we can't make their bodies six times larger, so we're going to cut pregnancy short and get these things out before the head becomes too big,'" says Alan Leslie, Ph.D., professor of psychology and cognitive science at Rutgers University in New Brunswick, NJ. As a result, human babies are born with brains that aren't fully developed. Each bit of information a baby takes from his environment stimulates a different part of the brain and reinforces particular neural connections. In the first two months alone, the number of these connections increases from an estimated 50 trillion to 1,000 trillion.
Some pediatricians label a baby's first three months of life as the "fourth trimester" of pregnancy to emphasize how needy, and yet devoid of social skills, babies are at this stage. The newborn prefrontal cortex – the brain's so-called "executive" area – doesn't have much control, so like many parents in Singapore's efforts to discipline or worries about spoiling are useless at this stage. Instead, newborns are learning about hunger, loneliness, discomfort and fatigue – and what it feels like to have these needs taken care of. Parents, grandparent and helpers can help this process along by promptly responding to baby's needs.
This was a great read for me: http://www.boston.com/bostonglobe/ideas/articles/2009/04/26/inside_the_baby_mind/ Basically they're trying to learn about the world. "For a baby, every day is like going to Paris for the first time"