Are you having difficulty falling asleep?Try drinking a glass of warm milk.If that doesn't work,listen to soft beautiful music.Still no luck?Try thinking about sheepjumping over a fence.If you are still awake,take a sleeping pill.But people who take pills often become dependent on the drugs.So you lie awake knowing that the new workday will soon arrive.If you have been in such condition for at least one month,you may have primary insomnia(失眠症)．

A new study has found that you might fall asleep more quickly and stay asleep longer if you try“cerebral hypothermia”.It is not a complex medical process.It just means cooling down your brain.Eric Nofzinger and Daniel Buysse from the University of Pittsburgh Medical School led the study.They examined twelve people who had sleeping problems.Twelve others had no sleeping problems.Each of them wore a soft plastic cap on their head at bedtime.

The caps had tubes inside filled with water.The researchers moved the water through the tubes and then changed the temperature of the water.Other studies showed that people who had sleeping problems often had more chemical reactions in the front of their brains.The researchers thought cooling down the brain might help.

On the first two nights of testing,the patients wore caps with no water.On the next two nights,the caps were worn,but the water was not cooled.Then the researchers cooled the water a little for another two nights.On the final two nights of the study,the temperature of the water was made much cooler.

The researchers found that the water caps didn't help the patients until the temperature was about 14℃.Most of the patients fell asleep faster and slept better when the coolest water was moving around their heads.

Dr.Nofzinger and Dr.Buysse noted that this was only the beginning of the brain temperature study.But they believed they had discovered something important that needed more research.

When we meet someone for the first time, we usually get a vague sense of what kind of person they are by the way they shake hands, talk, or walk. In the age of social networking, however, first impressions are sometimes made even before we actually meet someone in person---that is, by looking at their profile photo.

According to a recent study, these social images say a lot about our personality. In the study, presented in a paper at the International AAAI Conference on Web and Social Media, a group of researchers from the University of Pennsylvania in the US used software to analyze the profile pictures of 66,000 users of US social platform Twitter and 3,200 of their tweets. At the same time, about 434 participants were asked to complete a survey about their personality type. The researchers wanted to find out if there was a connection between personality traits—like openness, extroversion, and neuroticism(神经质)—and a person’s profile picture.

According to the results, open people are more likely to pose in an unusual way and use objects such as glasses or a guitar in their profile photo because they enjoy new and exciting experiences. Meanwhile, neurotic people often hold back their negative emotions. They try to avoid showing their face；Instead, they use an image of something like a pet, a car or a building.

Apart from the objects in profile pictures, the colors used in them also give us some hints about the photo’s owner. For example, extraverts were found to have the most colorful profile images, as they want to emphasize their personality and show themselves off, the researchers wrote.

Although social media photos “usually represent an extension of one’s self, they also allow a user to shape his or her own personality and idealized view,” according to the researchers. So, when choosing a profile photo, maybe we should ask ourselves first what kind of image we’d like to convey. After all, first impressions always last.