Can your brain make you see ghosts? The science behind the Bloody Mary legend

It’s Halloween night. Someone has dared you to turn off the lights and stand in front of the mirror. The rules are simple, stare into your reflection and say her name three times.

Bloody Mary. Bloody Mary. Bloody Mary.

According to the creepy urban legend, a terrifying figure will appear in the glass. Depending on which version of the story you follow, she might be a bloodied woman, a witch or a ghost seeking revenge. Sometimes, she simply appears behind you. In more sinister versions, she reaches out of the mirror.

Most of us encountered some variation of this story as children. Those brave enough to have tried it may even swear they saw a monstrous face appear in the mirror before them.

As tempting as it might be to believe that the monster you saw in mirror was something supernatural, the real explanation is perhaps even stranger. Your brain is perfectly capable of turning your own reflection into something you barely recognise.

The monster in the mirror

In 2010, Italian psychologist Giovanni Caputo published a study with the intriguing title Strange-face-in-the-mirror illusion. He asked 66 volunteers to sit approximately 40 centimetres from a mirror in a dimly lit room and look at their own faces for one minute.

Around two-thirds reported significant distortions of their faces. More than a quarter described seeing an unfamiliar person, while others reported fantastical beings, animals or the faces of relatives – sometimes........

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