Human eye movements for vision are remarkably adaptable

Once developed, that change in their “point of gaze” was retained over a period of weeks and was reengaged whenever their foveal vision was blocked. Tjan and his team say they were surprised by the rate of this adjustment. They note that patients with macular degeneration frequently do adapt their point of gaze, but in a process that takes months, not days or hours. They suggest that practice with a visible gray disc like the one used in the study might help speed that process of visual rehabilitation along. The discovery also reveals that the oculomotor (eye movement) system prefers control simplicity over optimality. “Gaze control by the oculomotor system, although highly automatic, is malleable in the same sense that motor control of the limbs is malleable,” Tjan says. “This finding is potentially very good news for people who lose their foveal vision due to macular diseases.
For the original version including any supplementary images or video, visit http://medicalxpress.com/news/2013-08-human-eye-movements-vision-remarkably.html

Your Eyes and Cornea Conditions

what conditions damage the cornea

The curvature of this outer layer helps determine how well your eye can focus on objects close-up and far away. There are three main layers of the cornea: Epithelium: The most superficial layer of the cornea, the epithelium stops outside matter from entering the eye. This layer of the cornea also absorbs oxygen and nutrients from tears. Stroma: The stroma is the middle and thickestlayer of the cornea and is found behind the epithelium. It is made up mostly of water and proteins that give it an elastic but solid form. Endothelium: The endothelium is a single layer of cells located between the stroma and the aqueous humor — the clear fluid found in the front and rear chambers of the eye. The endothelium works as a pump, expelling excess water as it is absorbed into the stroma.
For the original version including any supplementary images or video, visit http://www.webmd.com/eye-health/cornea-symptoms-treatments

Diabetes and eyes: What your vision is trying to tell you

Over time, diabetes may cause damage to the blood vessels in the back of the eye, known as diabetic retinopathy, which can lead to diabetic macular edema (DME). DME occurs when the damaged blood vessels leak fluid and cause swelling. Although symptoms are not always present, this swelling can cause blurred vision, double vision and patches in vision, which may appear as small black dots or lines floating across the front of the eye. Approximately 26 million Americans have diabetes and may be at risk for DME. More than 560,000 Americans have DME.
For the original version including any supplementary images or video, visit http://www.manilatimes.net/diabetes-and-eyes-what-your-vision-is-trying-to-tell-you/29492/

Leave a comment