The use of the term stress is now so integrated into our thoughts that it sometimes feels it has always been there. In fact stress, as we currently think of it, is a relatively new concept and is one that continues to evolve.
Stress through the centuries
Had we lived in the 14th century we would most certainly have used the term stress. But, with one or two notable exceptions, it would have had very little to do with our psychological state, except perhaps by implication. Stress had more to do with adversity, hardship, or some form of affliction. It was not until the 18th and 19th century that a shift in meaning started to occur.
As most people know, the 18th and 19th centuries are associated with a period of intense scientific and industrial progress. As the sciences developed, language adapted in order to both accommodate and articulate these changes.
The physical sciences, most notably engineering, began to use terms like stress, strain, resilience, pressure, and elasticity to describe the effects of materials. Nearly everyone will recognise these as expressions commonly used within medicine and psychology. Still others, like snapping or breaking point, tend not to be used within the professions these days, but they retain a position in everyday language relating to emotions or behavior.
Stress as a psychological concept
The adoption of the term stress as a psychological concept is frequently, if wrongly, attributed to Hans Selye in 1936. Selye had added to the developing ideas about stress by putting forward a three-stage process known as the general adaptation syndrome (GAS).
Selye stated that in response to some external stressor, we first react by mobilizing our physical resources to deal with or escape from the stressor. Selye called this the 'alarm' stage. The second stage, called 'resistance,' involves attempts to adapt to or cope with the external stressor. Thirdly, the stage of 'exhaustion' occurs if an individual is repeatedly exposed to the stressor and is unable to escape or cope.
As historians of psychology would be quick to point out, Selye actively avoided using the term stress until 1946. He was acutely aware of the fact that stress was much more closely associated with notions of 'nervous strain' and he was at pains to try to avoid criticism that his use was inappropriate. In terms of accuracy, it was Walter Cannon who actually developed the term stress in his work relating to the flight-or-flight response in 1915.
Today, the term stress can be used in different ways and for different purposes. If someone says they are under stress, we all know what they mean and in this sense, we have come to view stress as a negative experience. Psychologists also distinguish between stress that is harmful (distress) and stress that is positive (eustress). In research terms stress now embraces biochemical, behavioral, physiological and psychological effects.