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In brief : Rolling eyes gather more oxygen

点击量:   时间:2018-02-19 07:02:11

RAPID eye movement during dreams, thought to help the brain create vivid images, may have evolved to prevent the eye suffocating behind a closed lid, a physiologist in the US says. To reach the cornea when the eyes are closed, oxygen from blood vessels near the iris must cross a clear liquid called the aqueous humour. David Maurice of Columbia University, New York, stained his aqueous humour with a fluorescent dye. When he shut his eyes and kept them still, the stain stayed in a layer near the surface, but when he moved his eyes back and forth, the dye mixed rapidly. Maurice suggests in this month’s Experimental Eye Research (vol 66,