Basic Anatomy and Physiology of the Human Eye

Preview this chapter:

Basic Anatomy and Physiology of the Human Eye, Page 1 of 1

< Previous page | Next page > /docserver/preview/fulltext/9789815324334/chapter-1-1.gif

The eye is an exquisitely designed sensory organ adapted to respond to ambient white light. It is composed of many specialized structures and cell types that have defined functions. Good vision is important for us to perceive our environment and to conduct our daily life activities. In simple terms, the eyes detect light and convert it into electrochemical impulses, which the brain decodes into the final images we perceive. Thus, in higher organisms, the eye is a complex optical system that collects light from the surrounding environment, regulates its intensity through the pupil, and focuses it via the lens to form an image at the back of the eye. This image is then converted into a set of electrical impulse signals transmitted via the retinal ganglion cells (neurons) and their axons (bundled into the optic nerve) to the thalamic and suprachiasmatic nuclei and, ultimately, to the visual cortex. Visual perception in these higher brain systems, therefore, is reliant on proper and optimal functioning of all components of the retina-optic nerve-brain structure system. Defects along this visual axis result in many types of eye diseases of which glaucoma (made up of many disorders) is one of the major leading causes of worldwide visual impairment that can lead to blindness. The eye structure and function at a high level are described in this chapter.