During the mid-1980s, pockets of Australian keyboard operators suffered outbreaks of severe pain while typing or performing other repetitive work. Their pain could not be attributed to any discernible physical abnormalities. This best illustrates the role of in the perception of pain.

social-cultural influences

Explanation:

Social-cultural influences are are the larger scale forces and influences within cultures and societies that affect the thoughts, feelings and behaviors.

These larger scale of influences determines how cultures and societies affect how people act, what they feel and what they think.

The feeling of pain on the keyboard operators that cant be attributed to any physical discernable abnormalities is going to be attributed to a large scale force, because it affected the feelinh of people.

the answer to your question is,

old stone age.

-mabel < 3