4 . Our sense of smell, which we normally take for granted, is nowadays being increasingly used for purposes which might surprise us if we realized them.

One area in which smells are created to achieve particular results is marketing. For some time producers have taken advantage of our sense of smell with regard to household goods.

When pleasant smells are passed through a store’s air conditioning system, people tend to spend more time in the store and buy more. For example, the smell of chocolate is used in sweet stores, while the smells of leather and perfume are used in clothes stores.

In a test, people looked at the same types of shoes in two rooms— one filled with cleaned air, the other with a smell of mixed flowers. Eighty-four percent of the people preferred the shoes in the room with the smell of flowers. In fact, many said they would have paid up to US $10 more for a pair.

Smells also have other uses. Research has shown that certain smells can help to calm anxious people and increase their feeling of safety. Smells such as that of flowers and pine forests might therefore be used to relax patients in doctors’ and dentists’ waiting rooms, and to make the environment more pleasant and less stressful to them.

Some companies are experimenting with different smells to produce different effects on their workers according to the time of day.

For example, early in the morning they might put the smell of lemon in the air conditioning system to wake people up. In the middle of the morning, when the atmosphere tends to become more tense (紧张的), the smell of wood could be used to calm people down. Before lunchtime the smell of melting butter would encourage people to go to lunch on time. After lunch, when people often begin to lose attention, the smell of mint would increase their watchfulness.

While some of these uses of smells may be helpful and effective, not everyone would agree with their use to control customers in stores. It has been suggested by consumers’ organizations that one way to avoid this new subconscious (下意识) pressure to buy is to go shopping when people are less likely to be influenced by smells.

7 . Nicholas Epley, a behavioural scientist, and I conducted a series of studies and concluded that kind acts as simple as buying a cup of coffee for someone can promote a person’s happiness. Everyday life affords many opportunities for such actions, yet people do not always catch them.     1    

We firstly studied acts of kindness done for familiar people such as friends, classmates or family.     2     For instance, in one experiment, people wrote notes to friends and family “just because”. In another, they gave cupcakes away to workmates. Across these experiments, we asked both the person performing a kind act and the one receiving it to fill out questionnaires (问卷).

Across our studies, several strong patterns appeared. For one, both performers and receivers of the acts of kindness were in more positive moods than normal after these kind acts.     3     The receivers felt significantly better than the kind actors expected. The receivers also reliably rated these acts as “bigger” than the people performing them did.

    4    In one experiment, participants at an ice-skating rink (溜冰场) in a public park gave away hot chocolate to people they didn’t know on a cold winter day. Again, the experience was more positive than the performers expected for the receivers. Although the people giving out the hot chocolate saw the act as relatively small, it really mattered to the receivers.

These findings suggest that what might seem small when we are deciding whether or not to do something nice for someone else could matter a great deal to the person we do it for, These warm acts can improve our own emotional health and brighten the day of another person.     5    

8 . Episodic memory (情景记忆) allows humans to revisit past personal experiences in their minds, and it was once thought to be a special skill of humans. Although there are still arguments about the extent of this type of memory in non-human animals, scientists have proved that creatures like rats and dogs can pass tests that are developed to assess episodic memory over the past two decades. “Curiously, there is a lack of research investigating dolphins’ episodic memory,” University of Cambridge cognitive (认知的) scientist James Davies says. Therefore, this surprising fact encourages him to fill this gap.

The team used “where” and “who” questions in their research, each on a different test. Each dolphin was first trained to retrieve a ball from the water, and then trained to get a ball by approaching a person holding it in front of them while ignoring an empty-handed person standing at a different spot. During this training, the locations were randomized (使随机化) and the person holding the ball differed each time, so that those details were irrelevant to learning the retrieving behavior. Then, for the tests, the dolphins were asked to retrieve the ball as they had learned to do, but after 10 minutes, something changed-this time, the ball couldn’t be seen, as it was now behind one of the two people’s backs. In the “where” tests, the ball was hidden in the same spot as in the training, but both people had been changed, while in the “who” tests, the locations of the people changed but the ball remained with the person who’d had it previously.

Eight dolphins went through each of the two tests, separated by at least 48 hours. All the dolphins got it right in choosing the correct spot on the “where” experiments, and seven achieved success on the “who” experiments.

Kelly Jaakkola, a psychologist, says that based on their cognitive skills, dolphins are a good candidate for having episodic-like memory, and this study goes really far in showing that. She also says, “The more we look for such capabilities in non-human animals, the more species we’ll likely find them in.” She adds, “An exciting question is therefore ‘Where do we draw that line? Which animals do have it, which animals don’t, and what sort of cognitive or neurological or social characteristics do those animals share? ’ That’s going to be the fun part of the game.”

9 . Laughing together is an important way for people to connect and bond. And though the causes of laughter can vary widely across individuals and groups, the sound of a laugh is usually recognizable between people belonging to different cultures.

But what about animals? Do they “laugh”? And are the causes of animal and human laughter alike? In humans, people may laugh when they hear a joke, or when they see something that they think is funny, though it’s unknown if animals’ intelligence includes what humans would call a sense of humor.

However, many animals produce sounds during play that are unique to that pleasant social interaction. Researchers consider such vocalizations to be similar to human laughter. Recently, scientists investigated play vocalization to see how common it was among animals. The team identified 65 species that “laughed” while playing — most were mammals (哺乳动物), but a few bird species demonstrated playful laughter too. Reports of playful laughter were notably absent in studies describing fish, perhaps because there is some question as to whether or not play exists at all in that animal group. This new study could help scientists to analyze the origins of human laughter.

But how can we identify play? Unlike fighting, play is usually repetitive and happens independently of other social behaviors, said lead study author Sasha Winkler, a doctor of biological anthropology at the University of California. When it comes to identifying it, “you know it when you see it,” Winkler told Live Science. One sign is that primates — our closest relatives — have a “play face” that is similar to the expressions of humans who are playing.

When Winkler previously worked with rhesus macaques, she had noticed that the monkeys panted (喘气) quietly while playing. Many other primates are also known to vocalize during play, she said, so a hypothesis (laughter in humans is thought to have originated during play) supported by the play-related panting laughter of many primate species was put forward.

People now still laugh during play, but we also integrate laughter into language and non-play behaviors, using laughter in diverse ways to express a range of emotions that may be positive or negative. Human laughter notably differs from other animals’ laughter in another important way: its volume. People broadcast their laughter loudly, often as a way of establishing inclusion. By comparison, when most animals laugh, the sound is very quiet — just loud enough to be heard by the laugher’s partner.

“It’s really fascinating that so many animals have a similar function of vocalization during play,” Winkler told Live Science. “But we do have these unique parts of human laughter that are also an important area for future study."

10 . At a museum in Vietnam, Lena Bui’s film Where Birds Dance Their Last reflected on the beauty and vulnerability of Vietnamese feather farms after Bird Flu. During a festival in Rwanda, Ellen Reid’s audio experience Soundwalk was shared in a hopeful discussion about music, parks and mental health. These are a few of the things I have helped bring to life over the years, working at the intersection of scientific research, the arts and advocacy to support science in solving global health challenges.

Science is key to addressing these issues. But it isn’t the only key. To achieve its potential and for its advances to be implemented and reach all who could benefit, science depends on trust and good relationships. People might not always see science as relevant, trustworthy or meaningful to their lives. There are reasons why some see science as having a chequered past, from nuclear weapons to eugenics, and are therefore uninterested in, or suspicious of, what it proposes. Others feel excluded by the incomprehensibility of hyper specialist knowledge.

In its capacity to build upon and test an evidence base, science is powerful, but researchers and funders haven’t been as good at ensuring this evidence base responds to the needs and interests of diverse communities, or informs policy makers to take action. Science might be perceived as distancing itself from the personal, the poetic and the political, yet it is precisely these qualities that can be most influential when it comes to public interest in atopic or how a government prioritizes a decision.

A moving story well told can be more memorable than a list of facts. This is where the arts come in. Artists can give us different perspectives with which to consider and reimagine the world together. They can redress the proclaimed objectivity in science by bringing stories —subjectivities —into the picture, and these can help foster a sense of connection and hope.

In 2012, I set up artist residencies in medical research centres around the world. Bui was attached to the Oxford University Clinical Research Unit in Vietnam. The head of the research team was delighted, finding that Bui, as a Vietnamese artist, had license to be in, and to share useful insights from, villages where infectious disease researchers weren’t welcome. Six years later, I led Wellcome’s Contagious Cities program, which established artist residencies worldwide to support locally led explorations of epidemic preparedness. The recent pandemic made this work more noticeable, and has informed our Mindscapes program which is currently sharing experiences of mental health through the work of artists.

With pandemic, climate and mental health crises upon us, rising inequality and what feels like an increasingly broken world, never has there been more need to build and nurture hopeful and imaginative spaces to grow human connection and shared purpose for the common good. Science and the arts can work hand in glove to achieve this.