Hugging creates happiness

When your friend has a bad day, what will you do to comfort him or her? Hugging can help them feel better, Time reported.

According to scientists from Carnegie Mellon University in the US, hugs can be good for a person’s mood and stress levels. Hugging can increase positive (积极的) feelings and reduce negative (消极的) feelings.

Researchers talked to about 400 people. They asked them about their mood, whether they had any conflicts (冲突) with others and if they had a hug that day.

They found that when people experienced conflicts but didn’t get any hugs, they reported more negative feelings. But when people had both on the same day, they reported more positive feelings and fewer negative feelings.

When you receive a hug, your body releases a certain hormone (荷尔蒙). This hormone lowers blood pressure, as well as reduces stress and anxiety (焦虑), Michael Murphy from Carnegie Mellon told Time.

Of course, hugging is not the only way to comfort others. People sometimes give advice or just try to solve the other person’s problems directly. However, doing these things might make people feel like they’re being criticized (批评). But physical contact like hugging “makes people feel like they are cared about and have someone who is there for them,” Murphy said. “But that doesn’t make any judgments (about right or wrong).”

Scientists are still studying this effect. They want to know if it matters who the hug is from, or whether the person in question actually needs a hug. But Murphy said hugging is always a simple and helpful way to give support to someone you care about.

Sleep is necessary for our good health. Physically, we are relaxed. However, there are a lot of things going on in our brain while we are asleep. So our brain never really stops working.

Sleep helps the mind learn difficult tasks. It helps rover（追回）any forgotten knowledge or skills that people think they have forgotten during the day. Thus, their ability is restored after sleeping. Sleeping strengthens knowledge that is lost during the day and prevents it from being lost further. Thus, it plays an important role in learning new skills, strengthening them, and stabilizing（使稳固）memories so that these skills are kept in your memory forever.

Sleep helps in determining and sorting out（分出）things that we remember and forget. During sleep, the brain selectively stores those aspects of a memory which have a greater emotional value. At the same time, those that the brain considers as less valued are left out. The brain helps restore, restructure, and organize our memories, which may be the reason why people think out new ideas after a night’s sleep.

A study has confirmed that long-term memories are also formed during sleep. It is clear now that sleep helps us remember the order of particular events in our memories.

There are two stages of sleep: (1)NREM(non-rapid eye movement); (2)REM(rapid eye movement). May changes happen during the NREM, where our body relaxes and many other functions like brain activity, heart rate（心率）, blood pressure, and temperature of the body slow down compared（比较）to what they happen when we are awake.

The REM stage is an active stage when each of these processes increases beyond the level when we are awake. The REM stage is when most dreams happen, and according to the researchers, we spend about two hours every night dreaming. These dreams may be unclear or vivid images（生动的图像）where our brain is processing and gathering information during this stage.

Science can’t clearly explain many things about dreams as to why and how they happen. Therefore, we still have a long way to go to get a thorough（完全的） understanding of sleep and brain.