News tagged with eye

Related topics: brain , nerve cells , current biology , retina

Your eyes are half a billion years old

Look after your eyes – they are at least half a billion years old, and a good deal older than your brain. The eyes are one of our most remarkable and precious organs, yet their origins have been shrouded ...

Jul 30, 2013
popularity 4.3 / 5 (18) | comments 5 | with audio podcast

Learning to see better in life and baseball

With a little practice on a computer or iPad—25 minutes a day, 4 days a week, for 2 months—our brains can learn to see better, according to a study of University of California, Riverside baseball players reported in the ...

Feb 17, 2014
popularity 5 / 5 (7) | comments 0

Bionic eye maker has vision of the future

Robert Greenberg got tired of hearing from senior engineers that it wasn't possible to build his product idea: a bionic eye that gives sight to the blind. "A lot of the folks straight out of school didn't know any better, ...

May 06, 2013
popularity 5 / 5 (6) | comments 1

Eye

Eyes are organs that detect light, and send signals along the optic nerve to the visual and other areas of the brain[citation needed]. Complex optical systems with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in cnidaria, molluscs, chordates, annelids and arthropods.

The simplest "eyes", such as those in unicellular organisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes, retinal photosensitive ganglion cells send signals along the retinohypothalamic tract to the suprachiasmatic nuclei to effect circadian adjustment.

This text uses material from Wikipedia licensed under CC BY-SA