Lights, Camera, Action
When light hits the eye, the cornea helps the eye focus as light makes its way through. Behind the cornea are the iris, pupil, and anterior chamber. The iris is the colourful part of the eye. The iris has muscles attached to it that change its shape. This allows the iris to control how much light goes through the pupil.
The pupil is the black circle in the center of the iris, which is really an opening in the iris, and it lets light enter the eye. After light enters the pupil, it hits the lens. The lens sits behind the iris and is clear and colourless. The lens' job is to focus light rays on the back of the eyeball - a part called the retina.
Your retina is in the very back of the eye. It holds millions of cells that are sensitive to light. The retina takes the light the eye receives and changes it into nerve signals so the brain can understand what the eye is seeing.
Think of the optic nerve as the great messenger in the back of your eye. The rods and cones of the retina change the colours and shapes you see into millions of nerve messages. Then, the optic nerve carries those messages from the eye to the brain.
Tears also keep your eye from drying out, keep the eye moist and provide expression through laughter and crying.
Movement
Your eye muscles also need to be stretched. We tend to use our eyes in limited ways, staring at a computer screen, reading, driving and watching TV. For the most part we don't use our eye muscles fully. In this Kundalini Yoga Kriya for the eyes, you use all the muscles of your eyes, bringing circulation and a full range of motion available to your eyes. For optimal health, the eyes need exercise and rest.
Rest for the Weary
But what about eyestrain? The word is a bit of a misnomer, says Eli Peli, a professor of ophthalmology at Harvard Medical School. Peli says that vision happens in the brain, not the eyes; therefore, sitting at a computer isn't a strain for the eyes in the sense that it causes trouble for their muscles. Instead, the fatigue you feel is your brain asking for mercy. "The brain, in its smart way, projects fatigue onto the eyes, so you'll take a break."
Photo Credit: Conner Downey
By: Salimah Kassim-Lakha, Health & Yoga Expert at AgeComfort.org Health Care Resource Centre
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