Eyes - Vision



All About the Eye and Vision - Diseases - Wikipedia

An eye is an organ of vision that detects light. Different kinds of light-sensitive organs are found in a variety of organisms. The simplest eyes do nothing but detect whether the surroundings are light or dark, while more complex eyes can distinguish shapes and colors. Many animals, including some mammals, birds, reptiles and fish, have two eyes which may be placed on the same plane to be interpreted as a single three-dimensional "image" (binocular vision), as in humans; or on different planes producing two separate "images" (monocular vision), such as in rabbits and chameleons.




In the News ...


  Giving Sight by Therapy With Genes   New York Times - November 2, 2009

Physicists Explain How Human Eyes Can Detect Quantum Effects   PhysOrg - September 30, 2009

Virtual reality used for blind to map real world   MSNBC - September 17, 2009

Out of darkness, sight: How the brain learns to see   PhysOrg - September 17, 2009

Implanted tooth helps blind US woman recover sight   PhysOrg - September 16, 2009

Color-blindness Cured by Gene Injection in Monkeys   National Geographic - September 16, 2009

Eyes see trouble coming before brain notices   New Scientist - September 6, 2009

Device Lets the Tongue See   Live Science - August 27, 2009

What You Should Know About Glaucoma   Live Science - August 27, 2009

Scientists Program Blood Stem Cells To Become Vision Cells   PhysOrg - August 3, 2009

Humans Can Learn to "See" With Sound, Study Says   National Geographic - July 6, 2009

  Robotic "Eye-Cyte" May Bring Vision to Blind People   Live Science - March 21, 2009

  What you see affects what you hear   PhysOrg - March 4, 2009

  Bionic eye gives blind man sight   BBC - March 4, 2009

Vision Explained: Scientists Finally Capture Elusive Signaling Device Our Retinas Use To Tell Us What We See   Science Daily - February 2, 2009

Crystal (Eye) Ball: Visual System Equipped With 'Future Seeing Powers' Science Daily - May 16, 2008

   Bionic Eye Unveiled National Geographic - May 8, 2008

Scientists can tell date of birth by looking into eyes Telegraph.co.uk - February 26, 2008

Vision Loss Treatment For Age-related Macular Degeneration Looks Hopeful Science Daily - February 21, 2008
... a blinding eye disease that affects millions of people.
Macular Degeneration Wikipedia

New Contact Lenses Go Bionic Live Science - January 19, 2008

Gene therapy aimed at restoring sight for 30,000 people Guardian - May 2, 2007

Bionic Eyes Plug Directly into the Brain Live Science - April 27, 2007

Deep brain implants show bionic vision promise New Scientist - April 23, 2007

How irises 'reveal personality types BBC - February 20, 2007

How Do We See Red? Count the Ways NY Times - February 6, 2007

Genetics of eye colour unlocked BBC - December 20, 2006

Prosopagnosis: Inability to recognize faces BBC - July 27, 2006

Seeing double: brainwaves offer scientists key to unraveling how optical illusions trick the mind Scotsman.com - May 22, 2006

First Picture of Living Human Retina Reveals surprising variation from one person to the next Live Science - November 28, 2005

The Brain Sees What We Don't Live Science - November 1, 2005

Scientists prove blind people can 'see' with sixth sense Scotsman.com - November 1, 2005

New Book Explains Age-Old Mystery Of Geometrical Illusions Science Daily - October 3, 2005

Our eyes perceive only a fraction of the electromagnetic spectrum PhysOrg - September 26, 2005

Erotic images, gore cause temporary "blindness" PhysOrg - August 11, 2005
If your partner seems to be ignoring you after a flash of nudity on the television screen, it might not be his or her fault.

How the Brain Learns to See PhysOrg - June 9, 2005

The Mystery Of Eye Evolution Science Daily - November 2004

How optical illusions have played with our perception Guardian - October 2004

New York: 7-month-old Is Youngest Recipient Of Artificial Corneal Transplant Science Daily - January 2004

The Genetics Of Blindness Science Daily - October 2003

Blind 'see with sound' BBC - October 2003

Human eyes can be in two places at once ABC - July 2003

Eye Movement Studies To Help Diagnose Mental Illness Science Daily - June 2003

The Human Eye Can Self-correct Some Optical Faults Science Daily - February 2003

Futuristic System Brings Vision To Blind Science Daily - June 2002
A Japanese embryologist has grown and successfully transplanted artificial frogs' eyes using a type of stem cell




2000


Blind 'See' with Sound

The photograph of the bridge, top, was translated into the middle outline and conveyed through music to a blind subject. The subject produced the bottom image of the bridge using the musical description.

October 29, 2000 - AP

Two blind people in England were able to imagine and draw pictures of cars, buildings, landscapes - even a painting by Cezanne - that were all described to them through music. B.K., a 52-year-old man, and M.S., a 49-year-old woman, both lost their sight over 20 years ago. And yet, by training their ear to listen for images encoded into music, they were able to "see" images in their imagination.

The technique works by using a computer to digitize images and then relay them numerically into musical form. The length of horizontal lines are conveyed by how long a single note is held. Vertical lines are made going up or down the musical scale. The subjects' ears are then trained to hear what a certain line sounded like. For instance, a horizontal line of a certain length that's rising sounds like this, and vert one sounds like that. "So for example, I had an X, two diagonal bars crossing each other, you'd hear notes going down and up at the same time. They reach a point where they're the same note and then they diverge," said co-author Krisha Persaud said.

The subjects picked up the musical clues very quickly, said John Cronly-Dillon, a neuroscientist at England's University of Manchester and lead author of the study. "Within five minutes they can do something simple, like a triangle," he said. The technique wouldn't work on people blind since birth, who have no appropriate reference points in their visual vocabulary.

Distilling complex visual scenes into simple shapes via sound has its origins in artificial intelligence. "Because you want a computer to recognize a scene, the image is fed into the computer and it creates an internal 'image,'" said neuropsychologist and artificial intelligence expert, Richard Gregory at England's University of Bristol. "It's not unlike what we do when our brains take in and interpret an image," he said Pernaud agrees and notes that translating rich, complex images into simple shapes doesn't necessarily limit their functional value.

"It's the same way Picasso did," he said. "Where you can draw a few lines and that could identify an object. So we're not conveying everything there is in vision to a blind person, but we're giving them enough information to actually deal with the world." The study will be published in the Nov. 7 issue of Proceedings B from Britain's Royal Society. "Where we're going with this is hooking it all up to video so they can visualize everything immediately," Cronly-Dillon This would involve attaching video cameras to blind people that would continuously emit sounds corresponding to objects in their environment, allowing them to navigate without help. For example, a manhole would sound like a circle and Christmas tree like a triangle. Right now, B.K. and M.S. are using the video systems to walk about - albeit very slowly with little shuffling steps, said co-author Krisha Persaud.


Researchers identify color-blindness gene

June 26, 2000 - AP

Scientists have identified the defective gene that causes a debilitating total color-blindness among many inhabitants of a tiny Pacific island. The neurologist Oliver Sacks described the condition in the 1997 book "The Island of the Colorblind." The afflicted islanders see the world as if watching it on a black-and-white television. The discovery of the defective gene ends a 30-year search. Researchers said it will not lead to a treatment immediately but might help find one eventually. It could also lead to a test to tell islanders with normal vision whether they carry a flawed copy of the gene that would raise their children's risk of color-blindness. The disorder appears only in people who inherit a flawed copy from each parent. The island, Pingelap, is part of the Federated States of Micronesia. Of the 3,000 Pingelapese, some of whom live on nearby islands, about one in 20 is totally colorblind. That compares with a worldwide rate of one in 50,000. The flawed gene has been traced back to one man, who was among 20 survivors of a typhoon on Pingelap around 1775 who went on to re-establish the population. The condition differs from the relatively common color-blindness in which people cannot distinguish certain colors. Affected people on the island cannot see colors at all. They lack the sharp vision most people use to read, and their eyes are overwhelmed by sunlight - a particularly severe problem in the tropics.

In his book, Sacks noted that some affected islanders found work fishing by night. "They're about as handicapped as you can be," said Dr. Irene Hussels Maumenee, a member of the research team that first formally described the condition on Pingelap in 1970. "They stay in the cabin all day. They just don't see when they go out in the sunlight," said Maumenee, a professor of ophthalmology and pediatrics at the Johns Hopkins University School of Medicine. Their difficulty in reading hampers their schoolwork, and "people consider them very much as an outcast," she said. She is senior author of the paper announcing the finding of the gene, which appears in the July issue of the journal Nature Genetics. Total color-blindness is called complete achromatopsia. One other flawed gene for the condition had been identified before, but it clearly was not responsible for the problem on Pingelap. The discovery is "a really exciting result," said Maureen Neitz, who studies the genetics of color-blindness at the Medical College of Wisconsin.


Heredity, not age, main culprit in development of cataracts

June 14, 2000 - AP

Heredity plays a far larger role in the development of cataracts than widely blamed lifestyle factors such as smoking, according to a study. The finding could lead researchers to seek genes linked to cataracts and develop genetic tests to identify those most at risk. "I think this is a real breakthrough study," said Sheila West, a Johns Hopkins University cataract researcher. "I think this is exactly what we've needed to reorient our research on the genetic side."

Cataracts, which are a progressive clouding of the eye's lens, would develop in virtually all people if they lived to be 120 years old. But smoking and steroid drugs are seen as risk factors, while quality of diet and exposure to sunlight have also been implicated. A British team of researchers for the first time quantified the genetic component of age-related cataracts in a study published in Thursday's New England Journal of Medicine. The team studied 506 sets of identical or fraternal female twins ages 50 to 79. Identical twins, who develop from the same egg, are especially useful for such research because they are genetically the same. The researchers worked up an overall cloudiness score for patients' eyes and statistically analyzed the participants' age, heredity, lifestyles and environmental factors. They found that age explained 38 percent of cloudiness, but heredity accounted for even more at 48 percent. The other factors combined for just 14 percent. "It is not just your age that is the cause," said Dr. Christopher Hammond of St. Thomas' Hospital in London, who led the study.

At the same time, researchers cautioned that even 14 percent makes other factors very important, since cataracts are so common. Surgeon routinely operate on cataracts and replace the clouded-over lens with plastic. Congenital and disease-related cataracts are blamed on different causes than age-related cataracts. Another Hammond colleague, Dr. Clare Gilbert, said if future genetic tests identify who is most susceptible to cataracts, those people can then limit their exposure to the risks.


Blind 'to see' with artificial eye

April 27, 2000 - BBC

An "artificial eye" which would allow blind people to see is due to be implanted in a patient within the next few months. The device taps directly into the optic nerve and could restore some measure of sight to people whose retinas have been damaged or destroyed. Visual sensations beamed from a video camera are created in the brain by the artificial eye, developed by a team at the Catholic University of Louvain, in Belgium, directly stimulating different parts of the optic nerve. Other implants being developed stimulate the ganglia cells on the retina or the visual cortex of the brain itself. But the Louvain team, led by Claude Veraart, says these other techniques require large number of electrodes to create images which are recognisable. His device uses a coil to wrap round the optic nerve with only four points of electrical contact.

A video camera, positioned externally, transmits via a radio transmitter and microchip to an implant behind the ear. This is connected to the electrodes on the optic nerve. Different parts of the optic nerve are stimulated by altering the signals, similar to the way in which the electron guns in TVs are aimed at different parts of the screen. Veraart and his colleagues have spent the past two years experimenting with a volunteer who has the electrode implanted, with wires leading out of her body to the signal processor. By asking her to point in response to various stimuli, Veraart and his colleague Charles Trullemans have been able to map camera pixels onto the corresponding parts of her visual field. This was possible, said Veraart in New Scientist magazine, because the subject was once sighted and knows what it means to "look at" something. The researchers hope the device will at least allow blind people to avoid obstacles, though more tests are necessary before the device is implanted. Most critical is the time it takes to realise they are approaching an object. "If it takes her 30 seconds to recognise an obstacle it will be of little use," said Veraart. But if the reaction time is fast, the team plan to implant at least three more patients, starting in August. Rebecca Griffith, health promotion officer for the Royal National Institute for the Blind, in the UK, welcomed the advance but sounded a word of caution.




IRIDOLOGY


EYE SYMBOLOGY



HEALTH INDEX


ALTERNATIVE HEALING INDEX


ALPHABETICAL INDEX OF ALL FILES


CRYSTALINKS MAIN PAGE


PSYCHIC READING WITH ELLIE


2012 THE ALCHEMY OF TIME




Google