The Thatcher Effect

Do these photos look strange?
Aside from being upside down.

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Well, let’s turn them over

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The Thatcher effect was originally created in 1980 by Peter Thompson, Professor of Psychology at the University of York. The effect is a phenomenon where it becomes more difficult to detect local feature changes in an upside-down face, despite identical changes being obvious in an upright face. It was named after the British Prime Minister at the time, whose photo Thompson used to illustrate the effect.