Physiological stress, then, is the link between personality traits and disease. Certain traits — otherwise known as coping styles — magnify the risk for illness by increasing the likelihood of chronic stress. Common to them all is a diminished capacity for emotional communication. Emotional experiences are translated into potentially damaging biological events when human beings are prevented from learning how to express their feelings effectively. That learning occurs — or fails to occur — during childhood. The way people grow up shapes their relationship with their own bodies and psyches. The emotional contexts of childhood interact with inborn temperament to give rise to personality traits. Much of what we call personality is not a fixed set of traits, only coping mechanisms a person acquired in childhood.

There is an important distinction between an inherent characteristic, rooted in an individual without regard to his environment, and a response to the environment, a pattern of behaviours developed to ensure survival. What we see as indelible traits may be no more than habitual defensive techniques, unconsciously adopted. People often identify with these habituated patterns, believing them to be an indispensable part of the self. They may even harbour self-loathing for certain traits — for example, when a person describes herself as “a control freak.” In reality, there is no innate human inclination to be controlling. What there is in a “controlling” personality is deep anxiety.

The infant and child who perceives that his needs are unmet may develop an obsessive coping style, anxious about each detail. When such a person fears that he is unable to control events, he experiences great stress. Unconsciously he believes that only by controlling every aspect of his life and environment will he be able to ensure the satisfaction of his needs. As he grows older, others will resent him and he will come to dislike himself for what was originally a desperate response t

Environmental influences also affect dopamine. From animal studies, we know that social stimulation is necessary for the growth of the nerve endings that release dopamine and for the growth of receptors that dopamine needs to bind to in order to do its work. In four-month-old monkeys, major alterations of dopamine and other neurotransmitter systems were found after only six days of separation from their mothers.

“In these experiments,” writes Steven Dubovsky, Professor of Psychiatry and Medicine at the University of Colorado, “loss of an important attachment appears to lead to less of an important neurotransmitter in the brain. Once these circuits stop functioning normally, it becomes more and more difficult to activate the mind.”

A neuroscientific study published in 1998 showed that adult rats whose mothers had given them more licking, grooming and other physical-emotional contact during infancy had more efficient brain circuitry for reducing anxiety, as well as more receptors on nerve cells for the brain’s own natural tranquilizing chemicals. In other words, early interactions with the mother shaped the adult rat’s neurophysiological capacity to respond to stress.

In another study, newborn animals reared in isolation had reduced dopamine activity in their prefrontal cortex — but not in other areas of the brain. That is, emotional stress particularly affects the chemistry of the prefrontal cortex, the center for selective attention, motivation and self-regulation. Given the relative complexity of human emotional interactions, the influence of the infant-parent relationship on human neurochemistry is bound to be even stronger.

In the human infant, the growth of dopamine-rich nerve terminals and the development of dopamine receptors is stimulated by chemicals released in the brain during the experience of joy, the ecstatic joy that comes from the perfectly attuned mother-child mutual gaze interaction. Happy interactions between mother and infant generate motivati

Judgment or blaming is not the point. Understanding is.