Stress is caused by events or instances and these are called stressors.

Stress and Its Causes Stress is caused by events or instances that are beyond a personfs control and these are called stressors. Experts have been able to classify the different stressors into two categories and these are the processive and systematic kinds.
Processive stressors are those that require a form of mental activity. These are caused by having to process new information that is coming in. People who are plucked out from their comfort zones and placed in new environments are examples of those who experience stress through processive stressors. Understanding and learning to adapt to the new environment is indeed, stressful.
Systematic stressors are those that are caused by disturbances in onefs psyche or physical well being. Internal pains or intense emotions (caused by betrayal, deaths, births, loss of a job) are some examples of systematic stressors.
It is important to note that, although there are two different kinds of stressors, these normally occur simultaneously. For example, a person transferred to a new country and has to adapt to the lifestyle there (processive), because of this new change, he loses sleep and worries constantly about his new life (systematic).

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