Fraser’s Spiral

from Michael’s Visual Phenomena & Optical Illusions

Fraser image

What to do

The picture on the left depicts “Fraser’s Spiral”. If you place the mouse* over it, it becomes obvious that there are no spirals at all…


Fraser J (1908) A new visual illusion of direction. British Journal of Psychology; London 2:307–330

Morgan MJ, Moulden B (1986) The Münsterberg figure and twisted cords. Vision Res 26:1793–1800

Popple AV, Sagi D (2000) A Fraser illusion without local cues? Vision Res 40:873–878

Parts of Fraser’s original paper have been made available by Hervé Varenneere.

*On a touch device, tap the image. To “untap”, tap on the icon top right.