Credit: Tobyotter via flickr

By: Nala Rogers, Inside Science

(Inside Science) -- The spider's iconic leggy shape can abruptly yank our attention, even when we’re focused on something else, according to a new study. Other shapes such as houseflies and hypodermic needles don’t draw our attention in the same way. This suggests that spiders may be hard-wired into our visual systems, helping us avoid a threat that our ancestors faced for millions of years.

We assume that we can see the world around us in sharp detail but our eyes only process a fraction of our surroundings precisely.

In a series of experiments, psychologists at Bielefeld University investigated how the brain fools us into believing that we see in sharp detail. They find that our nervous system uses past visual experiences to predict how blurred objects would look in sharp detail.

Its central finding is that our nervous system uses past visual experiences to predict how blurred objects would look in sharp detail.

Almost 2 million Americans have an advanced form of age-related macular degeneration (AMD) and about 100,000 are blind from the disease. In AMD, cells in the retina, that layer of tissue in the back of the eye, begin to break down. What was once sharp central vision becomes blurry. 

Taking daily supplements of selenium and/or vitamin E appears to have no significant effect on the development of age-related cataracts in men, according to new findings from the Selenium and Vitamin E Cancer Prevention Trial (SELECT) Eye Endpoints (SEE) Study.  

Some research, including animal studies, has suggested that dietary nutrients can have an effect on the onset and progression of cataracts. Vitamin E and selenium are of particular interest.

A new paper believes it can measure the precision with which people make decisions - by pupil size before they are presented with any information.

Spontaneous, moment-to-moment fluctuations in pupil size predicted how a selection of participants varied in their successful decision making. A larger pupil size indicated poorer upcoming task performance, due to more variability in the decisions made once the relevant information was presented. The authors also found that certain individuals who had the largest pupils overall also tended to be the least consistent in their decisions.

Glaucoma, a condition where pressure builds from poor drainage of fluid from the anterior chamber of the eye, destroying retinal ganglion cells and eventually the optic nerve, is a leading cause of blindness in the U.S. but a cure has been elusive because the basis of the disease is poorly understood. 

In glaucoma, the eye becomes like a bathtub that can't drain because the pipe is clogged. The clogged or defective vessel, known as Schlemm's canal, is part of the lymphatic system that is essential for drainage in the eye. 

Exfoliation syndrome (XFS) is an eye condition that is a leading cause of secondary open-angle glaucoma and can lead to an increased risk of cataract and cataract surgery complications. 

People with more yellow pigment in their eye may be better able to see distant objects in hazy conditions, according to a new paper in Optometry and Vision Science.

Increased macular pigment (MP) may help in filtering out "blue haze," thus making distant objects more visible, according to an experimental study by Laura M. Fletcher, MS, and colleagues of University of Georgia, Athens. "The results suggest that people with high levels of yellow macular pigment may have some slight advantage in hazy and glare conditions," comments Anthony Adams, OD, PhD, Editor-in-Chief of Optometry and Vision Science.

Macular Pigment Affects Vision through 'Blue Haze'

Attention Deficit Hyperactivity Disorder (ADHD) is so commonly diagnosed – and overdiagnosed, and misdiagnosed – that it is hard to know what is based on evidence and what is based on teachers and concerned parents reacting to children that don't like to sit around and do nothing.

Actual clinical ADHD used to be rare but now it is a common problem of "pill culture" in psychiatry and the most common behavioral disorder label given to children in America, according to the Centers for Disease Control and Prevention.

Understanding eye diseases is tricky enough but knowing what causes them at the molecular level will help.

University of Iowa researchers have created the most detailed map to date of a region of the human eye long associated with blinding diseases, such as age-related macular degeneration. The high-resolution molecular map catalogs thousands of proteins in the choroid, which supplies blood and oxygen to the outer retina, itself critical in vision.

By seeing differences in the abundance of proteins in different areas of the choroid, the researchers can begin to figure out which proteins may be the critical actors in vision loss and eye disease.