Over the centuries, society's approaches to treating the mentally ill have shifted dramatically. At present, drugs that manipulate neurochemistry count as cutting-edge therapeutics. A few decades ago the heights of efficacy and compassion were lobotomies and insulin-induced comas. Before that, restraints and ice baths sufficed. Even earlier, and we've entered the realm of exorcisms.
Society has also shifted its view of the causes of mental illness. Once we got past invoking demonic possession, we put enormous energy into the debate over whether these diseases are more about nature or nurture. Such arguments are quite pointless given the vast intertwining of the two in psychiatric disease. Environment, in the form of trauma, can most certainly break the minds of its victims. Yet there is an undeniable biology that makes some individuals more vulnerable than others. Conversely, genes are most certainly important factors in understanding major disorders. Yet being the identical twin of someone who suffers one of those illnesses means a roughly 50 percent chance of not succumbing.
Obviously, biological vulnerabilities and environmental precipitants interact, and in this article I explore one arena of that interaction: the relation between external factors that cause stress and the biology of the mind's response. Scientists have recently come to understand a great deal about the role that stress plays in the two most common classes of psychiatric disorders: anxiety and major depression, each of which affects close to 20 million Americans annually, according to the National Institute of Mental Health