When you are concentrating on something, neural "noise" may cause you to miss important changes in your environment, new research indicates, and this binocular rivalry which occurs when the two eyes view radically different images means the brain temporarily rejects, or suppresses, one of those images in favor of the other.

The image that commands our visual awareness switches between the two over time. This fluctuation in visual awareness enables cognitive neuroscientists to study the neural correlates of awareness and consciousness.

A team of researchershas discovered a biological marker for neovascular age-related macular degeneration (AMD), the leading cause of blindness in older adults.  The marker, a receptor known as CCR3, shows strong potential as a means for both the early detection of the disease and for preventive treatment.

Neovascular (or "wet-type") macular degeneration is caused by choroidal neovascularization (CNV) – the invasive growth of new blood vessels in the thin vascular layer that provides nourishment and oxygen to the eye. Central vision loss occurs when these abnormal blood vessels invade the retina, the light-sensitive tissue that lines the inner surface of the eyeball.

Who says politics and science can't mix?   Well, we say they shouldn't mix but we're rare in science media.  Yet sometimes political events can make for great science studies too.

Case in point, the value neuroscientists at the University of Washington got when former President George W. Bush and Iraq's Prime Minister Nouri al-Maliki had shoes thrown at them by a crazy Iraqi 'reporter' during a Baghdad news conference. 

When Bush ducked and Maliki didn't flinch as the first shoe sailed toward them, it was a real-world example supporting the theory that there are two independent pathways in the human visual system. 

Seeing the world through 'rose-colored glasses'  may be more biological reality than metaphor, according to a University of Toronto study that provides the first direct evidence that our mood literally changes the way our visual system filters our perceptual experience.

The U of T team used functional magnetic resonance imaging to examine how our visual cortex processes sensory information when in good, bad, and neutral moods. They found that donning the rose-coloured glasses of a good mood is less about the colour and more about the expansiveness of the view. 

Erik Weihenmayer wears sunglasses often. He was wearing them to protect his eyes when he reached the summit of Mount Kilimanjaro in 1997. He had them on when he completed the 2003 Primal Quest, the world's toughest multi-sport adventure race. And, he put on a pair during a recent visit to the National Eye Institute (NEI).

But this last set is no ordinary pair of Oakley sunglasses. 

Weihenmayer looks through them, peering down at a white note card on a table. He silently moves his head back and forth, up and down. After a few moments, he says, "Is that a 12?"

Facial recognition is not as automatic as it may seem, according to researchers who have identified specific areas in the brain devoted solely to picking out faces among other objects we encounter.

Two specific effects have been established as being critical for facial recognition – holistic processing (in which we view the face as a whole, instead of in various parts) and left-side bias (in which we have a preference for the left side of the face). Psychologists Janet H. Hsiao from the University of Hong Kong and Garrison W. Cottrell from the University of California, San Diego wanted to test if these effects were specific for facial recognition or if they help us to identify other objects as well.

What's different about nocturnal mammals that have 'night vision'?  According to a Cell report, the DNA within the photoreceptor rod cells responsible for low light vision is packaged in a very unconventional way.   That special DNA architecture turns the rod cell nuclei themselves into tiny light-collecting lenses, with millions of them in every nocturnal eye.

Video may have killed the radio star(*) but violent video games may save the vision of teens who play them, according to a new Tel Aviv University study.

Dr. Uri Polat of Tel Aviv University's Goldschlager Eye Institute and his collaborators compared the effects of playing violent action games like "Unreal Tournament 2004" and "Call of Duty 2" to other video games which do not require high levels of visual-motor coordination, like "The Sims."

We all know that people sometimes change their behavior when someone is looking their way.   A new study in Current Biology shows that jackdaws, birds related to crows and ravens with eyes that appear similar to human eyes, can do the same. 

"Jackdaws seem to recognize the eye's role in visual perception, or at the very least they are extremely sensitive to the way that human eyes are oriented," said Auguste von Bayern, formerly of the University of Cambridge and now at the University of Oxford. 

Here's another reason why dieters should avoid all-you-can-eat buffets: When faced with a large variety of items, consumers tend to underestimate how much of each item is present, according to a new study in the Journal of Consumer Research.

Authors Joseph P. Redden (University of Minnesota) and Stephen J. Hoch (University of Pennsylvania) investigated consumers' perceptions of quantity in a set of experiments that may help us understand how quantity perceptions influence portion sizes.

"Does a bowl with both red and blue candies seem to have more or less than a bowl with only one color candy?" the researchers asked. "Contrary to popular belief, the presence of variety actually makes it seem like there are fewer items."