News tagged with eye

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

Umbilical cells help eye's neurons connect

Cells isolated from human umbilical cord tissue have been shown to produce molecules that help retinal neurons from the eyes of rats grow, connect and survive, according to Duke University researchers working with Janssen ...

Nov 24, 2015
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Curing cataracts without surgery?

Cataracts are very common. The Centers for Disease Control and Prevention estimates that 20.5 million Americans age 40 and over have them. Cataracts slowly cloud your vision, and people struggling with them say it's like ...

Nov 16, 2015
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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

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