Blind spot (vision) 4561848 219420340 2008-06-15T03:41:34Z 86.5.103.66 Removed external link that was just an search engine/advertising site. {{otheruses3|Blind spot}} <!--NB: There are other uses of "blind spot" in vision. --> A '''blind spot''', also known as a [[scotoma]], is an obscuration of the [[visual field]]. A particular blind spot known as ''' <u> the </u> blind spot''', or '''physiological blind spot''', or '''punctum caecum''' in medical literature is the place in the visual field that corresponds to the lack of light-detecting [[photoreceptor cell]]s on the [[optic disc]] of the [[retina]] where the [[optic nerve]] passes through it. Since there are no cells to detect light on the optic disc, a part of the field of vision is not perceived. The [[brain]] fills in with surrounding detail and with information from the other [[eye]], so the blind spot is not normally perceived. Although all [[vertebrate]]s have this blind spot, [[cephalopod]] eyes, which are only superficially similar, do not. In them, the optic nerve approaches the receptors from behind, so it does not create a break in the retina. The first documented observation of the phenomenon was in the 1660s by [[Edme Mariotte]] in France, at the time when it was generally thought that the point at which the optic nerve entered the eye should actually be the most sensitive portion of the retina [http://home.snafu.de/pedasy/ascapap.htm]. == External links == *[http://ourworld.compuserve.com/homepages/cuius/idle/percept/blindspot.htm Blind spot] [[Category: Eye|Blind spot (vision)]] [[Category: Vision|Blind spot (vision)]] [[de: Blinder Fleck (Auge)]] [[fr: Point aveugle]] [[he: הכתם העיוור]] [[it:Punto cieco]] [[ja: 盲点]] [[nl:Blinde vlek (biologie)]] [[no: Den blinde flekk]] [[pl: Plamka ślepa]] [[pt: Ponto cego]] [[ru: Слепое пятно]] [[sv: Blinda fläcken]] [[zh:盲點 (眼)]]