First three years of life

The quality of early experiences sets a trajectory of lifelong learning. The human brain physically changes in response to experience most efficiently during the first three years of life, compared to any other three-year period. Because brain architecture is more difficult to alter in later childhood, policies need to reflect current best evidence on how to ensure all children have access to high quality environments from before birth.

http://ilabs.washington.edu/i-labs-news/connecting-science-early-learning-policy