Also known as Mariotte's spot, physiological scotoma, physiological blind spot, and punctum caecum. All five terms are used to denote the physiological 'hole' existing in each monocular field of vision that corresponds morphologically with the optic disc, i.e. the region of the retina where the optic nerve ending is located, and where, as a consequence, no photoreceptors are present. Although humans and other vertebrates are blind to objects and visual stimuli in this part of the visual field, the missing perceptual information is automatically compensated for by the other eye in binocular vision, and 'filled in' by the brain (or mind, in a dualist reading) in monocular vision. The eponym Mariotte's spot refers to the French physicist and priest Edme Mariotte (c. 1620-1684), who in 1666 was the first to document the existence of the blind spot. In a broader reading, the term blind spot is used to denote any scotomatous region existing within the visual field. The so-called 'filling-in' of the blind spot is classified as a *fiction illusion.
References
Gregory, R.L. (1991). Putting illusions in their place. Perception, 20, 1-4. Mariotte, E. (1717). Oeuvres de Mr. Mariotte, de l'Académie Royale des Sciences; divisées en deux tomes. Seconde tome. Leide: Pierre Vander Aa.
Dictionary of Hallucinations. J.D. Blom. 2010.