Algodoo

When a human face is shown with its eyes upside down on a normal upside up face, it looks creepy and uncanny. If you then flip that face upside down so that the eyes look upside up, even though the head is upside down, the face tends to look normal. This oddity of how our brain interprets human faces is called the "Thatcher Effect", named after the previous Prime Minister of England, Margaret Thatcher. Google "Thatcher Effect" to learn more about it!

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