Making the Most of the First 3 Years

As you can see in the Baby Small video, the first three years of a baby's life are crucial to healthy brain development. During this important period of life, development of a baby's brain influences their long-term well-being. Scientific research continually bolsters and re-affirms the claim that a child is continually affected by her surroundings and experiences. Most importantly to note, a human's brain grows quicker and develops faster during the first years of life than during any other time of life. For example, by age three, a child's brain will reach eighty percent of its adult size.

The rate of physical growth for a baby's brain during this time is enormous, but what is even more fascinating is what happens in the brain and what the brain can do in these early years. At birth, a baby's brain contains nearly 100 billion nerve cells called neurons. Instead of creating new neurons as the brain grows, these neurons form networks of connections called synapses. New experiences create new connections, and as a baby is re-exposed to different experiences or activities, the synapses associated with those experiences are strengthened. Likewise, when a baby's brain is not regularly exposed to certain experiences, or when activities are not repeated, the synapses associated with those experiences are weakened and may even be eliminated for lack of use. The strength of synapses is important because synapses contribute to the connectivity and efficiency of the brain's networks that support memory, learning, and other cognitive abilities. A strong synapse allows better learning toward a particular area, while weaker synapses make future learning more difficult.

In other words, as a child grows, some synapses grow stronger while some synapses grow weaker. When a child continually experiences a loving, safe environment, listens to a parent reading a book out loud, or learns ways to communicate wants and needs, the specific pathways of synapses become stronger making these experiences more permanent and allowing further advancement. For example, research in recent years shows that language circuits in the frontal and temporal lobes of the brain consolidate within the first year of life. Thus, these lobes are strongly influenced by the language an infant hears. This means that even though an infant does not communicate with words yet, the language they hear, through a parent's talking or reading, is already wiring a their brain to be able to speak and learn their language. Contrary, a baby who is not surrounded with talking and reading will have a lesser-developed language circuits and will have a harder time learning language and literacy. Additionally, the brain can only process a certain amount of information. If a child experiences a toxic home environment, the brain will prioritize the strengthening of more ‘survival-like' synapses than other synapses like synapses associated with memory or critical thinking skills.

For the first three years of a child's life, parents have the opportunity and responsibility to provide the necessary experiences for optimal brain development. In the coming editions of Research to Policy, we will discuss how promoting the overall wellness of young children promotes stronger brains, and how children with positive early experiences are more likely to be properly equipped for success not only when they reach school, but also later in life. Providing a child with positive early experiences not only supplies her with essential life-skills—language and self-control, but also gives her a better outlook in terms of health, educational and socio-emotional outcomes.


Mangina CA, Sokolov EN. (2006). Neuronal plasticity in memory and learning abilities: theoretical position and selective review. International Journal of Psychophysiology. 60, 203-214.

Johnston MV, Ishida A, Ishida WN, et al. (2009). Plasticity and injury in the developing brain. Brain & Development, 31,1-10.