Comparative biologists have suggested that if it weren't for the size limitations of a woman's pelvis, babies would stay developing in the womb for considerably longer. To fit through mom's, er, escape hatch, the newborn brain is one-quarter the size of an adult's.
(A newborn baby's brain weighs less than 0.5kg)
Some evolutionary biologists theorize that newborns are socially inept – and have an annoying cry – so that parents won't get too emotionally attached while the baby has an increased likelihood of dying. Of course, crying also gets a baby the attention he needs to survive.
(So we won't get too emotionally attached? What planet do their biologists come from?)
The newborn prefrontal cortex – the brain's so-called "executive" area – doesn't have much control, so efforts to discipline or worries about spoiling are pointless at this stage. Instead, newborns are learning about hunger, loneliness, discomfort and fatigue – and what it feels like to have these pains relieved. Caregivers can help this process along by promptly responding to baby's needs, experts suggest.
Not that a baby can be kept from crying. In fact, all babies, no matter how responsive their parents are, have a period of peak crying around the gestational age of 46 weeks. (Most babies are born between 38 and 42 weeks.)
That is, a premature baby, born at 34 weeks, will reach her peak crying point at around 12 weeks old, while a full-term baby, born at 40 weeks, will cry the most at around 6 weeks old.
After birth, the human brain grows rapidly, more than doubling to reach 60 percent of its adult size by the time the tot is sampling his first birthday cake. By kindergarten, the brain has reached its full size but it may not finish developing until the kid is in his mid-20s. Even then, "the brain never stops changing, for better or worse."
(By the time a person is 6 years old, the brain reaches its full weight of about 1.4 kg. Most of the brain cells are present at birth, and so the increase in weight comes mainly from growth of the cells.)
Baby brains have many, many more neuronal connections than the brains of adults. They also have less inhibitory neurotransmitters. As a result, researchers have suggested, the baby's perception of reality is less focused than adults. They are vaguely aware of pretty much everything – a sensible strategy considering they don't yet know what's important.
"The only thing we know of, that makes babies smarter, is talking to them," emphasizing that dialogue is best, where a parent responds within the pauses of an infants' vocalizations.
Some parents take advice too far and strive to meet Junior's every yip with a yap. But when babies get a reaction 100 percent of the time, they get bored and look away.
(I don't agree with that statement - "the only thing...makes babies smarter is talking to them". I believe also in the positive educational value of reading to your children from the word 'go'.)
When acting instinctually, parents respond to 50 to 60 percent of a baby's vocalizations. In the lab, it has been found that language development can be accelerated when babies are responded to 80 percent of the time. Beyond that, however, learning declines.
(Also, it is very easy to overstimulate and tire your baby, who also needs quiet time to rest and absorb what he is learning.)