Extra Visual Function of the Human Eye.

Abstract

Abstract The eye is part of the sensory nervous system. However, there are a number of organ systems that also work with the eye. The retina is the only tissue in mammals that regulates photoreception due to the presence of photoreceptors, the rods and cones and performs both visual and non-visual functions Light plays a fundamental role in the behavior of almost all organisms. In addition to visual processes, light also induces important physiological responses. People with mild vascular disease that causes damage to the retina in the eye are more likely to have problems with thinking and memory skills. Everyone has a natural body clock that they are born with and all organs in the body operate according to biological rhythms. Our experiments with ophthalmic mutant rats also showed that the loss of vision also hampered their physiological activities and their rhythmicity was also disturbed. The menstrual cycle disturbances and age of menarche are regulated by many factors; nevertheless, blindness is one of the most impotent factors in regulating biological clock dependent functions. The human eyes are the only organs in the body capable of “seeing”- wavelengths of light and turning it into visual images. We can't “see” or get a visual image to the brain without eyes. The eye-like ability of skin to sense light by using a receptor (Cryptochrome) but failed to form image. Photoreceptors contain chemicals that change when they are hit by light. This causes an electrical signal, which is then sent to the brain along the optic nerve. Different types of photoreceptor allow us to see an enormous range of light and colours. There are two types of photoreceptors in the human retina, rods and cones. Rods are responsible for vision at low light levels (scotopic vision). They do not mediate colour vision and have a low spatial acuity. The blind: People who have lost their sight have different experiences. Some describe seeing complete darkness, like being in a cave. Some people see sparks or experience vivid visual hallucinations that may take the form of recognizable shapes, random shapes and colours, or flashes of light. An afterimage is an image that continues to appear in the eyes after a period of exposure to the original image. Afterimages occur because photochemical activity in the retina continues even when the eyes are no longer experiencing the original stimulus.