The visual pathway predominantly travels beneath the cortex for most of its length. Visual signals in the optic nerves may intersect at the chiasma and then proceed through the optic tracts. The term Ayurveda derives from two words: "Ayu," meaning life, and "Ved," signifying knowledge or science. Therefore, "AYURVEDA" as a whole translates to "the science of life." According to Ayurvedic principles, the universe consists of five funda-mental elements. The body maintains an ideal equilibrium of these elements, and any disruption to this balance results in a state of unhealthiness we refer to as illness. The classical texts of Ayurveda provide detailed insights into the physiology of the sense organs, sensation, perception, and the mind's role in the perception process in an exceptional manner. Indriya (sense faculty) serves as the specialized tool that helps the soul in recognizing even the slightest changes in both the external and internal environments. Indriya acts as the essential element that differentiates living entities from non-living ones. The concept of Indriya pancha panchak, introduced by Achar-ya Charaka, delves into both the anatomical and physiological features of the sense organs. The five sensory faculties include sight (chakshurendriya), hearing (shrotrendriya), smell (ghranendriya), taste (rasanendriya), and touch (sparshnendriya). Each sensory faculty is associated with a specific object: sound (shabda) pertains to hearing, touch (sparsha) relates to the tactile sense, color (rupa) corresponds to sight, taste (rasa) is associated with the gustatory sense, and smell (gandha) links with the olfactory sense organ. Every sensory faculty pos-sesses an excess of one material element. Developed from particular material constituents, each specific sense faculty perceives the properties of its corresponding element. The mechanics of how the external world is per-ceived is referred to as the visual process or the physiology of vision. Ayurveda introduces a special concept known as the Tridosha theory. The three fundamental elements of the human body are collectively termed Tridosha (Vata, Pitta, Kapha). The Tridosha governs the physiological and voluntary activities of the body. Ayur-veda elaborates on the physiology of vision by considering the roles of vata and pitta. Pitta encompasses five different types: Ranjak, Pachak, Alochak, Sadhak, and Bhrajak. The "Alochak Pitta" is recognized as the seat of "Drishti." The retinal pigments Rhodopsin, Iodopsin, and Melanin symbolize Alochak Pitta. Alochak pitta is fur-ther categorized into two types: chakshu vaisheshik located in the eye and buddhi vaisheshik found in the brain. There are three stages in this visual process: the light refraction phase, the phase in which light energy is trans-formed into an electrical impulse, and lastly, the peripheral and central neurophysiology involving the geniculate bodies and optic radiations prior to synapsing in the occipital cortex.
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