Despite the intervening six decades of scientific inquiry…

““Despite the intervening six decades of scientific inquiry since Selye’s groundbreaking work, the physiological impact of the emotions is still far from fully appreciated. The medical approach to health and illness continues to suppose that body and mind are separable from each other and from the milieu in which they exist. Compounding that mistake is a definition of stress that is narrow and simplistic. Medical thinking usually sees stress as highly disturbing but isolated events such as, for example, sudden unemployment, a marriage breakup or the death of a loved one. These major events are potent sources of stress for many, but there are chronic daily stresses in people’s lives that are more insidious and more harmful in their long-term biological consequences. Internally generated stresses take their toll without in any way seeming out of the ordinary. For those habituated to high levels of internal stress since early childhood, it is the absence of stress that creates unease, evoking boredom and a sense of meaninglessness. People may become addicted to their own stress hormones, adrenaline and cortisol, Hans Selye observed. To such persons stress feels desirable, while the absence of it feels like something to be avoided. When people describe themselves as being stressed, they usually mean the nervous agitation they experience under excessive demands — most commonly in the areas of work, family, relationships, finances or health. But sensations of nervous tension do not define stress — nor, strictly speaking, are they always perceived when people are stressed. Stress, as we will define it, is not a matter of subjective feeling. It is a measurable set of objective physiological events in the body, involving the brain, the hormonal apparatus, the immune system and many other organs. Both animals and people can experience stress with no awareness of its presence. “Stress is not simply nervous tension,” Selye pointed out. “Stress reactions do occur in lower animals, and even in plants, that have no nervous systems…. Indeed, stress can be produced under deep anaesthesia in patients who are unconscious, and even in cell cultures grown outside the body.” Similarly, stress effects can be highly active in persons who are fully awake, but who are in the grip of unconscious emotions or cut off from their body responses. The physiology of stress may be triggered without observable effects on behaviour and without subjective awareness, as has been shown in animal experiments and in human studies.””

— Gabor Maté