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Macula
 Here is an excerpt from a brilliant description of the anatomy and the physiology of the macula and the fovea in the retina by Dr. W.H.Bates, which I decided to reproduce as such only, for the benefit of my readers: "The eye is a miniature camera, corresponding in many ways very exactly to the inanimate machine used in photography." "In one respect, however, there is a great difference between the two instruments."  "The sensitive plate of the camera is equally sensitive in every part; but the retina has a point of maximum sensitiveness, and every other part is less sensitive in proportion as it is removed from that point." "This point of maximum sensitiveness, in the center of the macula lutea, is called the fovea centralis, literally the central pit." "The retina, although it is an extremely delicate membrane, varying in thickness from one-eightieth of an inch to less than half that amount, is highly complex." 
"It is composed of nine layers, only one of which is supposed to be capable of receiving visual impressions." "This layer is composed of minute rodlike and conical bodies which vary in form and are distributed very differently in its different parts." "In the center of the retina is a small circular elevation known, from the yellow color which it assumes in death and sometimes also in life, as the macula lutea, literally the yellow spot." "In the center of the macula is the fovea, a deep depression of darker color." 
"In the center of this depression there are no rods, and the cones are elongated and pressed very closely together." "The other layers, on the contrary, become here extremely thin, or disappear altogether, so that the cones are covered with barely perceptible traces of them." "Beyond the center of the fovea, in the macula and more so farther, the cones become thicker and fewer and are interspersed with rods, the number of which increases toward the margin of the retina." "The precise function of these rods and cones is not clear; but it is a fact that in the macula, at the center of the fovea, where all elements except the cones and their associated cells practically disappear, is the seat of the most acute vision." "As we withdraw from this spot away from the macula, the acuteness of the visual perceptions rapidly decreases." "The eye with normal vision, therefore, sees one part of everything it looks at best, and everything else worse, in proportion as it is removed from the point of maximum vision; and it is an invariable symptom of all abnormal conditions of the eyes, both functional and organic, that this central fixation is lost."  "These conditions are due to the fact that when the sight is normal the sensitiveness of the macula and the fovea is normal, but when the sight is imperfect, from whatever cause, the sensitiveness of the macula and the fovea is lowered, so that the eye sees equally well, or even better, with other parts of the retina." "Contrary to what is generally believed, the part seen best when the sight is normal is extremely small." "The text-books say that at twenty feet an area having a diameter of half an inch can be seen with maximum vision, but anyone who tries at this distance to see every part of even the smallest letters of the Snellen test card - the diameter of which may be less than a quarter of an inch - equally well at one time will immediately become myopic." "The fact is that the nearer the point of maximum vision approaches a mathematical point, which has no area, the better the sight." The acutest vision comes from focusing the light on the fovea - this is what is called the central fixation of the eye or third eye opening! Now the rods, employing a sensitive photo-pigment called rhodopsin, are more light-sensitive as well as more in number, although not color-sensitive; hence they provide a much better peripheral vision - better known as scotopic vision - required for tracking motion in wide-angled field of vision, whereas the cones provide a much better visual acuity when directly looking at the point of visual interest - better known as central vision, requiring central fixation of the eye or third eye opening! I invite you to subscribe to my weekly E-zine titled Third Eye-zine. This weekly E-zine publishes rare, revolutionary articles which are of real use in the day-to-day life of a common man, covering topics concerning the effect of third eye opening on health, diseases, personality, performance, efficiency, relationship, sex, mind, creativity, passion, business, management, and energy level of a person; apart from its effect on vision correction. A not-to-be-missed opportunity! Subscribe to it here: I also invite you to subscribe to my Third Eye Blog - no need to provide your e-mail address here. This RSS feed keeps you informed about new developments taking place on this site. It also harbors my weekly Third Eye Bloglet narrating My Story : My Date with My Body - a bloglet about vision, mind, sex, science, and society. A real interesting reading! In order to subscribe to the blog, right-click on the orange RSS button (see buttons up to the left) and then paste the URL into your RSS reader. Or click on add to My Yahoo! button or My MSN or Add To Google button if you keep a personalized home page there. If you are not sure what RSS or blogging is all about, click on What's an RSS Feed? here:
Return from Macula to Human Eye
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