高中英语语法填空:短文题型基础练习 Test 18

Some colors that people see late at night could cause signs of the condition mental health experts call clinical depression. 　61　 was the finding of a study that builds on 　62　 (early) study findings. They show that individuals who live or work in low levels of light overnight can develop clinical depression.

In the new study, American investigators designed an experiment that 　63　 (expose) hamsters to different colors. The researchers chose hamsters 　64　 they are nocturnal, which means they sleep during the day and are active at night.

The animals were separated into 4 groups. One group of hamsters was kept in the dark during their nighttime period. Another group was placed in front of a blue light, 　65　 third group slept in front of a white light, 　66　 a fourth was put in front of a red light.

After four weeks, the researchers noted how much sugary water the hamsters drank. They found that the more depressed animals drank 　67　 least amount of water.

Randy Nelson heads the Department of Neuroscience at Ohio State University. He says animals that slept in blue and white light appeared to be the most depressed.

“What we saw is these animals didn't show any sleep disruptions at all 　68　 they did have mucked up circadian clock genes and they did show depressive phenotypes whereas 　69　 they were in the dim red light, they did not.”

He says there's a lot of blue in white light, this explains 　70　 the blue light and white light hamsters appear to be more depressed than the hamsters see red light or darkness.