1 . A quick increase of dopamine (多巴胺) shifts mice into a dreamy stage of sleep. In the mice’s brains, the chemical messenger triggers rapid-eye-movement sleep, or REM, researchers report in the March 4 Science.

These new results are some of the first to show a trigger for the shifts. Understanding these transitions in more detail could ultimately point to ways to treat sleep disorders in people.

Certain nerve cells in the ventral tegmental area of the mouse brain can pump out dopamine, a molecule that has been linked to pleasure, movement and learning, which is then delivered dopamine to the amygdalae, two almond-shaped structures deep in the brain that are closely tied to emotions.

Using a molecular sensor that can tell exactly when and where dopamine is released, the researchers saw that dopamine levels rose in the amygdalae just before mice shifted from non-REM sleep to REM sleep.

Next, the researchers forced the mice into the REM phase by controlling those dopamine-producing nerve cells using lasers and genetic techniques. Compelled with light, the nerve cells released dopamine in the amygdalae while mice were in non-REM sleep. The mice then shifted into REM sleep sooner than they typically did, after an average of about two minutes compared with about eight minutes for mice that weren’t prompted to release dopamine. Stimulating these cells every half hour increased the mice’s total amount of REM sleep.

Additional experiments suggest that these dopamine-making nerve cells may also be involved in aspects of narcolepsy (嗜睡症). A sudden loss of muscle tone, called cataplexy, shares features with REM sleep and can accompany narcolepsy. Stimulating these dopamine-making nerve cells while mice were awake caused the mice to stop moving and fall directly into REM sleep.

The results help clarify a trigger for REM in mice; whether a similar thing happens in people isn’t known. Earlier studies have found that nerve cells in people’s amygdalae are active during REM sleep.

Many questions remain. Drugs that change dopamine levels in people don’t seem to have big effects on REM sleep and cataplexy. But these drugs affect the whole brain, and it’s possible that they are just not selective enough.

2 . What was once science fiction is now a part of our everyday lives, as artificial intelligence (AI) is something that many of us live alongside. According to Statista, in 2019, 3.25 billion virtual assistants were used worldwide and that figure is predicted to be more than double by 2014.

AI is doing more for us than setting reminders, making recommendations, and offering us weather reports. In fact, it could be about to change the healthcare landscape entirely. It is estimated that one in eight people today use health apps regularly. And AI has more to offer.

Dr Emilia Molimpakis is a neuroscientist who co-founded thymia, a platform that uses AI powered games to help doctors spot depression.

“I was inspired to start thymia after seeing my best friend struggle with depression,” she says, “I saw her try to go through the psychiatric (精神病学的) system and fall through the cracks. Despite being seen by a psychiatrist, she ended up trying to take her own life. When that happened, I was the one who found her, and this experience impressed me.”

Aside from blaming herself for not recognizing the signs sooner, what she could not get her head around was how the psychiatrist should not see this coming. She realized that the tools psychiatrists used were still these old-fashioned, pen-and-paper questionnaires that have been found, time and again, to be subjective and not reflecting a patient’s actual mental health status. So, thymia was born.

But as we look into the future, what should we be aware of? Before we dive in head-first, there are still questions we need to answer. As Dr Molimpakis points out, it’s vitally important that AI tools used in healthcare must be trained on a diverse data set that is typical of all groups of people. It should also be used alongside, and in addition to, professional care—not as a replacement. We should also consider carefully how our health data is stored and used. These are topics that both users and professionals have a responsibility to consider.

3 . Paris Baker is a 30-year-old mother who has two daughters, Kallie, nine, and Harper, five.

One day, the three were playing at home. Harper was playing mom, feeding her mother, then her teddy bear and finally herself. Suddenly, Paris started choking on a piece of cookie. Soon, the cookie was at the back of her throat. The two girls started hitting her back at once. After about a minute of hitting her back, Kallie went to call an ambulance as she started to worry. As she did this the other girl carried on doing what she had been doing and thankfully the cookie finally came up.

Paris was diagnosed (诊断) with motor neurone disease (MND) in 2017, and was told she had five years to live. The condition will gradually paralyse (使……瘫痪) her, leaving her trapped inside her body.

Due to her condition, she’s more likely to fall and has received serious injuries. She felt it was very important to teach her girls what to do in a dangerous situation she might be in. This included applying pressure to a bleeding wound, what to do if someone is choking and how to call emergency services.

The girls know that if their dad isn’t home and an emergency happens there are three steps. Step one is to ring 999, ask for an ambulance and give their address. Step two is to put their dogs in the garden, and step three is to open the front door for the emergency services.

After the accident, Paris was so grateful that she had taught her daughters what to do in such a situation. But accidents like that can happen to anyone. So if your kid hasn’t learned first aid skills yet, it’s time to do that now.

4 . What would happen today, if there was an accident at your workplace? Would employees know what to do? Would the injured person get the best possible care?

When an accident happens, a first-aid programme that meets the requirements of the law and is made to the type and size of the workplace can really make a difference between life and death, or between recovery and lasting disablement (伤残).

Employers should make sure that all employees know where emergency information is posted at the workplace. The emergency notice should show the phone numbers of the closest ambulance service, rescue unit, fire police station, and hospital. The amount of time it takes to look up one of these important numbers can make a big difference to a seriously injured person. The place of first-aid equipment and rescue equipment should also be posted.

All workplaces should have a person with first-aid or medical training in case of an emergency. First-aid equipment and supplies, including a variety of dressings and instruments, as well as an up-to-date first-aid book, should be stored where they can be reached quickly and easily in case of an accident. These supplies should be inspected frequently, making sure they are kept in sanitary (卫生的) and usable conditions and re-stored after use. Larger workplaces may need more than one fully-equipped first-aid bag.

In lonely workplaces, emergency supplies and an action plan are especially important. At least one person trained in first aid should always be on-site (在现场的). If first aid is not given properly, it can sometimes hurt rather than help an injured person, or even be harmful to the person giving first aid.

All workers should know who is trained to give first aid on-site, where first-aid equipment is put, and what medical professionals or medical instruments should be found if a medical emergency happens.

5 . Jiao Junying, 46, is a clinic doctor in Nanjie village, Neiqiu town, Xingtai, in North China’s Hebei province. He has been awarded many honorary titles in the province. When he was young, Jiao got polio(脊髓灰质炎) which resulted in his disability. This spurred him on to achieve his childhood dream to become a doctor and bring health to more people.

Since 2015, Jiao has become the contracted family doctor for the villagers in Nanjie, and has become the “health manager”. From measuring blood pressure, writing prescriptions, and popularizing knowledge about health and well-being, Jiao’ s daily schedule is packed. He regularly conducts physical examinations for the village elderly and does follow-up visits for chronic diseases, and maintains health records for the villagers. In addition, Jiao studies traditional Chinese medicine and constantly enriches his knowledge.

“The recognition by the villagers is a great trust and encouragement for me. As long as the villagers still need me, I am willing to always protect their health.” Jiao says.

He can’t remember how many home visits he has made in the past six years and how many patients he has treated, but every patient he treats remembers him. With a good heart, he is the health goalkeeper closest to the common people. Jiao says that by escaping death, he understands the preciousness of life and is more willing to protect the health of others.

In Jiao’s view, from poverty alleviation(扶贫) to rural revitalization, China’ s policies are getting better and better, and the medical conditions in rural areas are improving. He is willing to stick to the cause.

In the new medical reform, the construction of the basic medical and health system has been further promoted, and Jiao has another task - to establish health records for the villagers.

6 . Scientists believe they have found help for older people suffering from poor eyesight. The solution is shining a special red light in the eyes for three minutes. Staring at a deep red light for three minutes a day can greatly improve falling eyesight, finds a new University London-led (or UCL-led) study, the first of its kind in humans. They believe the discovery could signal the dawn of new affordable home-based eye therapies (疗法), helping millions of people globally with naturally falling eyesight.

Doctors say a three-minute daily dose of the special red light for two weeks could help improve age-related vision problems. However, they say not any red light will help improve eyesight. The co-author of a study into the effects of red light and vision in older people explained why. Professor Glen Jeffery said: “I strongly suggest that people do not just go and buy a red light off the web. They have to produce the right wavelength (波长) and be reliable. We are looking for a business partner to do this and to price them at under around $20 to $25.”

The study was carried out by a team from University College London. Researchers conducted tests on 24 men and women aged between 28 and 72. They said some cells that help us process light had worsened in the older people.

Doctors say their red light improved the ability of these people to detect different colors, particularly blue. The vision of these older people improved by as much as 22 percent. Doctor Jeffrey said: “Populations are ageing rapidly and this is going to be a major issue in the future. We need to gear up (为……做准备) for this.” He added: “If you can’t see clearly you can’t read or watch TV. You also tend to fall down and break bones. Our lights are a step in this direction.”