The cerebral cortex forms from the inside out; neurons are ‘born’ and then travel outward to where they are supposed to be, or close to it, before beginning to establish connections with other neurons to form different systems. This means that during gestation that 10,000,000,000 neurons travel the highways to their destinations and as might be expected not all of them arrive at their proper place. Even the ones that do may not connect properly. These isolated neurons die off and are removed in a process called apoptosis. This continues during infancy and early childhood so that cells that are not integrated into active systems or that do not receive stimulation from other cells die off. And so our brains are shaped into each individual’s pattern of strengths and weaknesses.
Now consider the process of attachment whereby the mother or father interact with their baby, helping it to self soothe and call attention and pay attention and enjoy life. Back in the 70s and 80s a pediatrician, T. Berry Brazelton, called attention to this rhythmic dance between mother and baby. A researcher, Daniel Stern, extensively studied it with perhaps a bit more scientific rigor.
Thus a child is led to experience the full range of basic emotions from joy to sorrow and their passage in communion with their parents during this same period when under-stimulated neurons die off. So each individual’s brain is shaped in part by the stimulation inherent in the early attachment process.
Now consider when attachment does not go well, the child is reared in a deprived environment like a Romanian orphanage during Ceausescu’s regime or by a parent who is emotionally unavailable due to illness such as cancer, depression or substance abuse. These children are often later described as having flat affect, which means that they do not show a full range of emotion and indeed, many seem to experience feelings and to socialize quite differently from a securely attached child. Some seem almost feral in how they seek to survive and relate. Fortunately humans are resilient and capable of thriving across a broad range of experience. Our attachment contributes early on to our risk and resilience in very basic ways.