Reviewing the recent research on early brain development, we became excited about the fact that synaptic connections certainly included the tangible aspects of day-to-day child care and the formation and strengthening of child/parent relationships. We saw these relationships concretized in the multiplicity of synaptic connections presented in the figure on “Rapid Synaptic Growth.” This clearly offers the opportunity to show that “bonding” (as here defined) is not merely a psychological matter but is a complex pattern embedded in synaptic connections, and is as physical and real as genes.
How the brain develops hinges on a complex interplay between the genes you're born with and the experiences you have. Clear evidence has emerged suggesting that the structure of the brain is not simply genetically determined, but depends on activity, experience, attachment, and stimulation. Some synaptic connections, those that are formed early in life and strengthened by day-to-day contact over a period of three to twelve months, are relatively permanent.
Genes and environment interact at every step of brain development, but they play different roles. Generally speaking, genes are responsible for the basic wiring plan – for forming all of the cells and the general connections between different brain regions. Experience is responsible for fine-tuning these connections, helping each child to adapt to his or her particular environment. An analogy that is often used compares brain development in early childhood to the wiring of a phone network. Genes would specify the number of phones and the major trunk lines that connect one relay station to the next. Experience would specify the connections between the relay station and each person’s home or office. Once established in early life, these connections are difficult, if not impossible to modify.
Neurons are rapidly connecting from the moment of birth. Synapses are fashioned. Memes are being formed, “cultural” ways of thinking and doing things. Synapses self-organize themselves into complex clusters which in turn form the connectome. Bonding to a specific person is one way of organizing a variety of sensory life experiences. The earlier these connections are made, the more difficult they will be to change or reverse. Memes parallel genes. The connectome parallels the genome. Memes and the connectome are fixed early and are relatively irreversible. They are as physical as genes and the genome.