FLICK PHOSPHENE

flick phosphene: translation

   Also known as eye-movement phosphene. The term flick phosphene was introduced in or shortly before 1957 by the American ophthalmologist Bernard R. Nebel, who had observed the concomitant phenomenon in himself. The term is used to denote a type of *phosphene (i.e. a transient flash or spark of light) that can be evoked under physiological circumstances by rapid eye movements (REMs). As described by Nebel, "The 'flick phosphene' is best observed in the dark-adapted well-rested eye, i.e. before dawn after a restful sleep. Then if one flicks the eyes, e.g. from left to right, with the lids closed, one observes in each monocular field the short-lived appearance of a bright pattern." This pattern tends to be sheaf like, and to point in the direction of the sudden eye movement. Its colour is usually whitish, with some blue or orange added against the darkness of the background. The flick phosphene is classified as an * entoptic phenomenon. It is traditionally attributed to a primary deformation of the retina, caused by the torsional forces of relative movement occurring at the interface of retina and vitreous. Conceptually as well as phenomenologically, the flick phosphene is considered closely akin to * Moore's lightning streaks and the * fiery rings of Purkinje. The term is used in opposition to the terms *convergence phosphene, *movement phosphene, and * sound phosphene.

   References

   Nebel, B.R. (1957). The phosphene of quick eye motion. Archives of Ophthalmology, 58, 235-243.