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The brain, rather than our eyes, may be more important for sight, researchers studying fruit flies(果蝇) have discovered. The discovery could change the way we think about vision.

Researchers in the University of Virginia have found that the very simple eyes of fruit fly larva(幼虫), with only 24 total photoreceptors (the human eye contains more than 125 million), provide just enough light input to allow the animal’s large brain to make that input into images. Their discovery shows that vision may be less important to “seeing” than previously thought—and in fact it is the brain’s ability to process points of light into complex images that is key.

“It blows open how we think about vision.” said Barry Condron. “This tells us that visual input may not be as important to sight as the brain working behind it.”

Condron’s graduate students, Elizabeth Daubert, Nick Macedonia and Catherine Hamilton, conducted a series of experiments to test the vision of fruit fly larvae. They found that when a larva was tied to the bottom of a dish, other larvae were attracted to it as it attempted to free itself. After several further experiments to understand how they sensed the motion, the researchers learned that the nearly blind animals likely were seeing the action.

“The answer must be in the brain of these animals.” Condron said. “They are able to take just a couple dozen points of light and then process that into recognizable images, something like when an astronomer with a small telescope is able to use techniques to improve a limited image into useful information about a star.” Condron believes the animals are able to assemble useful images by rapidly scanning their heads and, in doing so, gather up enough light points to allow the brain to compose an image clear enough to “see”.

The researchers tested this by presenting larva with a video (therefore no sound and no smell), and found that the larvae still sensed and sought out the struggling larva on the video. This provides us with a good model for trying to understand the role that the brain plays in helping organisms, including humans, to process images, such as recognizing faces.

【语篇导读】本文是一篇说明文，作者用果蝇的实验以及其他实验说明了大脑对视力的作用比眼睛的作用更大。