Fantastical or monstrous beings

Douglas Heaven has an interesting article on a phenomenon observed by the psychologist Giovanni Caputo, in which staring fixedly at a reflection of one's own face in a darkened room gives rise to weird and disturbing distortions and spectres.

"Usually, after about 1 minute of mirror-gazing, the eyes start to move or shine, the mouth opens, or the nose becomes very large," [Caputo] says. "If you continue to gaze there are very big changes, until completely new faces appear." And it's not just human faces that are seen – some report seeing animals and others fantastical or monstrous beings. 

Perhaps, as the brain struggles to make sense of what it is seeing in the dim light, it pulls scraps from our memory to make up for our poor perception – perhaps patching together a “photo fit” of different features so that it begins to look like another person.

I'm reminded of something referred to here: an experience Jorge Luis Borges describes in a lecture  in 1977 -- recurring nightmares which, like much of his fictional output, feature labyrinths and mirrors. In the most terrible of all, he sees himself reflected in a mirror but the reflection is wearing a mask such as he had feared greatly in childhood. “I am afraid to pull the mask off, afraid to see my real face, which I imagine to be hideous. There may be leprosy or evil or something more terrible than anything I am capable of imagining.”