Mental Filter

Broadly speaking

In the 1940s, the British psychologist Donald Broadbent heralded the arrival of Cognitive Psychology with his work on selective attention. He described it as a "mental filter", claiming that from the wealth of things going on all around them, people only focus on the important things, like today's football results or whether Julia Roberts is going to risk another wave at the crowd. Psychologists have called this issue the 'cocktail party problem': how you filter out a tedious conversation about mortgage rates when you are trying to eavesdrop on a nearby conversation about the surprising uses of a sink plunger.

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