The early years of life are especially critical for the development of the human brain and responsive parenting plays an important role. The Center on the Developing Child at Harvard University indicates that genes provide a blueprint for this development but the child’s family environment is also very important:
A major ingredient in this developmental process is the serve and return interaction between children and their parents and other caregivers in the family and community. In the absence of responsive caregiving – or if responses are unreliable or inappropriate – the brain’s architecture does not form as expected, which can lead to disparities in learning and behavior.
For more on this topic from the Center on the Developing Child, see Key Concepts: Brain Architecture.