Vision

Nearly all species have some ability to detect light and at least three types of cells in the retina allow us to see images or distinguish between night and day. Now, researchers at the Johns Hopkins School of Medicine say they have discovered another type of cell that can sense light and contribute to vision.

Reporting in Nature, the team of neuroscientists say that retinal horizontal cells, which are nerve cells once thought only to talk to neighboring nerve cells and not even to the brain, are light sensitive themselves. 
A study by the University of Barcelona (UB) has analysed which facial features our brain examines to identify faces. Our brain adapts in order to obtain the maximum amount of information possible from each face and according to the study the key data for identification come from, in the first place, the eyes and then the shape of the mouth and nose.
A toxic molecule implicated in cell damage and disease  may also be essential for bird migration, according to the University of Illinois. They propose the molecule superoxide as a key player in the mysterious process that allows birds to 'see' Earth's magnetic field.
Your color vision is not for seeing red sunsets or green grass; rather, it evolved as a kind of empath sense, optimized to detect the changes in blood physiology in the skin of the faces (and rumps) of others, thereby sensing their emotions.

Your forward-facing eyes are not for seeing in depth, but, rather, for significantly enhancing how much you can see in the cluttered forest habitats of your ancestors.
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.