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Volume 25       April 23, 2012

Publication for our patients.

You may have seen a child wearing an eye patch to strengthen a lazy eye. After the age of 12, an eye patch doesn't improve a lazy eye. So why did adult pirates wear eye patches? One of the common myths about pirates is that they wore an eye patch to hide an injured eye. The real reason, however, has to do with helping vision in the dark situations. There are 2 different types of photoreceptors in the retina: cones are used for color vision and bright situations and rods are for dark situations. It takes 10-15 minutes for the eye to switch from bright vision to dark vision. Wearing a patch over one eye keeps that eye "dark adapted", so moving from the bright light on the deck of the ship to below deck where there is no lighting is easier. They just have to switch the patch over to the other eye.

The Mystery Spot just outside Santa Cruz features a house where the laws of visual perception and gravity are mysteriously bent. When inside or around the house, everyone appears to be slanted with respect to the floor, roof, and doorways. The reality is the house is on a slant on the side of a hill. The brain takes visual cues from the structure of the house assuming that the house is level. Everything else, in comparison, looks tilted because of this illusion. So everything unattached to the house follows the laws of gravity. They explain the mystery by saying extraterrestrials may have buried unearthly metals underground.

Not only is Dr. Lee a talented eye doctor at PVI, he is also a talented artist. Check out his very funny eye cartoons here.

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