Also known as phosphene. Both terms are used to denote a type of *photopsia (i.e. a 'flash of light') consisting of an unformed shape. The term unstructured photopsia is used in opposition to * structured photopsia. Pathophysiologically, the mediation of unstructured photopsia has historically been associated primarily with aberrant neu-rophysiological activity in the retina and other peripheral parts of the visual system, although theoretically any part of the visual system may be involved in their mediation.
References
Amos, J.F. (1999). Differential diagnosis of common etiologies of photopsia. Journal of the American Optometric Association, 70, 485-504.
Dictionary of Hallucinations. J.D. Blom. 2010.