The first three years of life are a period of incredible growth in all areas of a baby's development. A newborn's brain is about 25 percent of its approximate adult weight. But by age 3, it has grown dramatically by producing billions of cells and hundreds of trillions of connections, or synapses, between these cells. While we know that the development of a young child's brain takes years to complete, we also know there are many things parents and caregivers can do to help children get off to a good start and establish healthy patterns for life-long learning.
Infants prefer human stimuli--your face, voice, touch, and even smell--over everything else. Most adults (and children) find infants irresistible, and instinctively want to nurture and protect them. The kind of attention we most want to shower them with—touching, holding, comforting, rocking, singing and talking to—provides precisely the best kind of stimulation for their growing brains.
Normal, loving, responsive caregiving seems to provide babies with the ideal environment for encouraging their own exploration, which is always the best route to learning.
The one form of stimulation that has been proven to make a difference is language: because language is fundamental to most of the rest of cognitive development, the simple action of talking and listening to your child is one of the best ways to make the most of his or her critical brain-building years.
Source: Zero to Three: www.zerotothree.org