How the eye is suited for the purpose of converting visible light into neural activity and how visual information is then conveyed to the visual cortex - Essay Example

Download file to see previous pages The paper will also highlight some of the challenges the eye faces while it performs its functions.
The eye’s first adaptation to its interaction with light is referred to as the papillary light reflex. When responding to different levels of light, the rods and cons work independently but back up each other. This modus operandi espouses the eye’s adaptation to dark light.. While the rods are sensitive to light, they have the tendency to take a significant amount of time to adapt to darkness, in this case the rhodopsin, situated in the photoreceptors take full charge through photo bleaching. On the other hand, the regulation of the eye’s sensitivity eye’ s to light is espoused by the changes in the intracellular calcium ions. In order to adapt to light, the eye first adapts to the background so that it is capable of detecting and distinguishing the background objects; the entire process of adaption to light takes a period of approximately five minutes
Whenever light is reflected on a surface or remitted from an object, the eye detects the light that first encounters the cornea; from here, it is then focussed to the lens. The lens in turn functions to vary the focus depending on the distance that exists between the eye and the object. The focal adjustment of the light by the lens is called accommodation. The lens alters its shape depending on the distance of the object; for objects that are distant, it elongates, flattens and pulls out whereas for objects that are close by, it only needs to assume its natural round shape for clear vision. The light first passes through the space between the cornea and the lens that is filled with fluid called aqueous humour. It consequently goes through the t pupil ‘s circular aperture that is surrounded by the iris diaphragm muscles prior to going through the lens (Jones, et al 2004). However, the quantity of light that passes through the pupil is determined by the pupil’s diameter and still goes ahead to be ...Download file to see next pagesRead More