The
visual system is the part of the
central nervous system which gives organisms the ability to
process visual detail, as well as enabling the formation of several non-image photo response functions. It detects and interprets information from
visible light to build a representation of the surrounding environment. The visual system carries out a number of complex tasks, including the reception of light and the formation of monocular representations; the buildup of a nuclear binocular perception from a pair of two dimensional projections; the identification and categorization of visual objects; assessing distances to and between objects; and guiding body movements in relation to the objects seen. The psychological process of visual information is known as
visual perception, a lack of which is called
blindness. Non-image forming visual functions, independent of visual perception, include the
pupillary light reflex (PLR) and circadian
photoentrainment.