Apparently you can tell how people think by the way they move their eyes.
up and right (their right) – for constructed, imagined images e.g. you floating on air or you with blue hair
up and left – for remembered images e.g. scenes from your holiday
sideways right – for constructed sounds e.g. your boss talking in a donald duck voice
sideways left – for remembered sounds e.g. your favourite piece of music
down and right – for feelings and internal emotions e.g. the touch of silk
down and left – for internal dialogue e.g. what you say to yourself before you give an important presentation
straight ahead, defocused – for visual images remembered or created e.g. the faces of your close friend
– Sue Knight, NLP at Work
To confuse matters left handed people may have the meaning of looking left and right reversed.