It stems from a perception that you are somehow breaking unspoken rules, are not meeting some perceived standard or are just not good enough for the task at hand.
The recent warning by the Financial Action Task Force, the world's premier standard-setting body for countering terrorist financing and money laundering, confirms the extraordinary risks that accompany doing business with Iran.
The results of the BOE paper indicate that the real task at hand is to create a 21st century international gold standard that would promote trade and prosperity throughout the world.
Before beginning the study, participants were given standard cognitive tests, many involving executive-function tasks such as concentration and shifting from one mental task to another.