2 . When evaluating people on various psychological tests, psychologists often distinguish between markers of absolute performance and relative performance. Absolute performance reflects the raw measurement of something, like the time it takes to run a mile. Relative performance is how a person rates in relation to their peers, as in what place a runner gets in a race.

The standards we use to evaluate ourselves are almost always relative, as we compare ourselves to our peers and the standards that are most familiar to us. Our conscious recognition of these peers and norms is what sets our expectations, shaping our self-image and happiness. What’s interesting about the relative comparisons that most of us make is that in whatever area of life we consider—for example, our highest level of education—it’s not how we fare in comparison to the rest of the world that seems to matter most, but rather how we compare to our closest peers.

For instance, in my private practice, I have one patient I will call “Omar” who is dependent on social services and makes less than $30,000 per year at his job. While this level of poverty would lead most people to wake up depressed each day, Omar is one of the most optimistic and appreciative individuals I know. Why? Because most of his closest peers—his siblings and friends from childhood—have lives far worse than his.

In contrast to. Omar, I have another patient, an adolescent I’ll call “Lena”, whose family has property over $5 million. Lena, however, lives in an upper-class neighborhood where her family is at the lower end of the income level. Though Lena’s family allows her to enjoy possessions and experiences that less than 1 percent of her peers across the world can share, she consistently feels “less than”. Why? Because Lena doesn’t compare herself to the rest of the world; This is too abstract an exercise for her, as it would be for most of us.

Accordingly, whether a psychologist is psychodynamic or cognitive-behavioral, therapy (疗法) with individuals struggling with situation al or psychological depression aims to solve the problems associated with basing one’s self-worth on comparisons with others. Psychologists try to help people focus on personal growth around the achievement of concrete goals in line with their values independent of the achievement of others. For all of us, defining these goals, especially during Periods of emotional calm, can go a long way in helping us to avoid the trap of relativity that often leads to situational and psychological depression.

In life, once on a path, we tend to follow it, for better or worse. What’s sad is that even if it’s the latter, we often follow a certain path anyway because we are so used to the way things are that we don’t even recognize that they could be different. Psychologists call this phenomenon functional fixedness.

This classic experiment will give you an idea of how it works — and a sense of whether you may have fallen into the same trap:

People are given a box of tacks (大头钉) and some matches and asked to find a way to attach a candle to a wall so that it burns properly. Typically, the subjects try tacking the candle to the wall or lighting it to fix it with melted wax (石蜡). The tacks are too short, and the candle doesn’t fasten to the wall. So how can you accomplish the task? The successful technique is to use the tack box as a candle holder. You empty it, tack it to the wall, and stand the candle inside it.

To think of that, you have to look beyond the box’s usual role as a container just for tacks and reimagine it serving an entirely new purpose. That is difficult because we all suffer — to one degree or another — from functional fixedness. The inability to think in new ways affects people in every corner of society. The political theorist Hannah Arend coined the phrase frozen thoughts to describe deeply held ideas that we no longer question but should. In Arendt’s eyes, the complacent reliance on such accepted “truths” also made people blind to ideas that didn’t fit their worldview, even when there was ample evidence for them. Frozen thinking has nothing to do with intelligence, she said, “It can be found in highly intelligent people.”

Another context in which frozen thinking can turn truly dangerous is medicine. If you land in the hospital, it’s natural to want to be treated by the most experienced physicians on staff. But according to a 2014 study in the Journal of the American Medical Association (JAMA), you’d be better off being treated by the relative novices.

4 . It’s hard to turn down hamburgers, French fries, potato chips and all of the other junk food that seem to call out to us. However, eating too much junk food can harm your body, particularly if you’re between the ages of 10 and 19.

“Junk food shapes adolescent brains in ways that impair (损害) their ability to think, learn and remember. It can also make it harder to control impulsive (冲动的) behaviors, said Amy Reichelt, a brain and nutrition specialist at Western University, Canada. “It may even increase a teen’s risk of depression and anxiety.”

Reichelt and two other researchers reviewed more than 100 studies, including their own, about how poor food choices can impact adolescent brains. They found adolescents are more sensitive than any other age group to processed foods with a lot of fat and sugar as their brains are not yet fully formed.

Adolescent brains are still developing the ability to assess risks and control actions. The prefrontal cortex (前额皮质) is the part of the brain that tells us we shouldn’t eat chips all the time and helps us resist that urge. However, this region is the last to mature — it doesn’t fully develop until we are in our early 20s.

Meanwhile, teen brains get more buzz (兴奋) from rewards. The parts of the brain that make us feel good when we do something pleasurable — like eating tasty foods — are fully developed by the teen years.

In fact, these regions are even more sensitive when we are young. That’s because dopamine (多巴胺), a natural chemical that lifts our mood when we experience something good, is especially active in adolescent brains.

Therefore, the teen brain has two strikes against it when it comes to resisting junk food. “It has a heightened drive for rewards and reduced self-regulation,” said Reichelt.

Reichelt and her team conducted their own study using mice, whose brains develop much like our own. They discovered that the “teenage” mice that had a high-fat diet performed worse on memory tests than those eating a normal diet. Researchers said the high-fat diet may make the mice’s prefrontal cortex work less effectively.

So, what’s the best way to say no to junk food? Researchers suggest exercise. When we exercise, the brain’s reward system becomes less sensitive to food cues (线索). Exercise also triggers the body to make a protein that helps brain cells grow and boosts connections between the prefrontal cortex and other brain regions. The prefrontal cortex thus can work better to help us make wise decisions and control our impulses.

6 . In 2012, James Cameron, creator of Avatar and Titanic, became the first person to reach the Challenger Deep. When he arrived at the deepest spot on Earth at 7 miles below sea level, he spent hours mapping the region and taking photos and samples.

“As human beings, we’re drawn to absolutes—the deepest, the highest, the coldest, the farthest.” he says. “And as a storyteller and curious monkey, I just wanted to see what was there.” The answer is obvious—plastic and more. “Our so-called civilization is using the ocean as its toilet,” Cameron says. “Unless this changes, ocean ecosystems are going to continue their rapid collapse.”

Despite decades of environmental studies, the impact of plastic and other forms of pollution on oceans are not entirely understood. Initial studies appear to indicate that ingesting them-either directly or indirectly-could cause disease. Plastics can also release poisonous substances into the water, which could potentially impact animal populations.

But plastic is just one of the problems facing oceans that have yet to be fully understood. “Plastic waste in the ocean is horrifying but is only the most obvious of our many deadly waste streams, which include carbon that’s heating the atmosphere and making the ocean acidic, and the run-off nutrients from all the world’s agriculture, which is causing anoxic dead zones the size of countries,” Cameron says.

Oceans, like the rest of the world, are impacted by the burning of fossil fuels and the release of greenhouse gases like carbon dioxide-about 30 percent of which is absorbed by the sea. This absorption causes ocean acidification, where the pH level is altered to become more acidic. As a result, it’s harder for some creatures to form shells and skeletons and countless species at the base of the food web can struggle to survive, which, scientists say, has the potential to cause huge disruptions to entire ecosystems. Indeed, ocean acidification is thought to have played an important role in Earth’s worst-ever mass extinction event 252 million years ago.

The effect of climate change on the world’s oceans will likely worsen in coming decades. Last June, scientists announced carbon dioxide levels had reached the highest levels since human records began. The last time carbon dioxide levels were this high was during the Pliocene era, between 3 and 5 million years ago, when global temperatures were about 4 degrees Celsius warmer than they are today. Current climate models suggest that if greenhouse gas emissions continue on their current trend, we may be on course to see 4 degrees of warming by 2100.

As a result, understanding the role oceans have on global systems is becoming more and more important.

8 . It will come as no comfort to a child shivering (打哆嗦) on a playing field on a cold winter’s day. But regular organized school sport helps children in their academic studies in years to come. The researchers said other “structured” activities such as music or religious activities were not as beneficial for attention as taking part in a games lesson. The difference in academic ability was noticeable even at age ten, with those who had taken in sports since the start of junior school performing better than those who hadn’t.

The Canadian study looked at children aged six and then ten. Professor Linda Pagani said:“We worked with information provided by parents and teachers to compare kindergarteners’ activities with their classroom activities as they grew up. By the time they reached the fourth grade, kids who played structured sports were clearly better at following instructions and remaining focused in the classroom. There is something special to the sporting environment — perhaps the sense of belonging to a team to a special group with a common goal — that appears to help kids understand the importance of respecting the rules and honoring responsibilities.”

Researchers began studying 2,694 Canadian children around the age of six, with teachers filled in questionnaires about their behavior in school. Meanwhile, the children’s parents were interviewed by phone or in person about their home life. The exercise was the repeated four years later to test what effect the behavior had.

Professor Pagani said: “We found children who had better behavior in the kindergarten class were more likely to be involved in sport by age ten. Nevertheless, we found those children who were specifically involved in team sports at kindergarten scored higher by the time they reached the fourth grade.” The researchers believe sporting activities and attention skills go hand in hand. Professor Pagani added: “The results should be encouraging for schools looking to cut childhood obesity rates and low attainment in schools.”

10 . Biologists from the John Innes Centre in England discovered that plants have a biological process which divides their amount of stored energy by the length of the night. This solves the problem of how to portion out（分配） energy reserves during the night so that the plant can keep growing, yet not risk burning off all its stored energy.

While the sun shines, plants perform photosynthesis（光合作用）. In this process, the plants change sunlight, water and carbon dioxide into stored energy in the form of long chains of sugar, called starch（淀粉）. At night, the plants burn this stored starch to fuel continued growth.

“The calculations are precise so that plants prevent starvation but also make the most efficient use of their food,” said study co-author Alison Smith. “If the starch store is used too fast, plants will starve and stop growing during the night. If the store is used too slowly, some of it will be wasted.”

The scientists studied the plant Arabidopsis, which is regarded as a model plant for experiments. To give the plants some math tests, the biologists let night arrive unexpectedly early or late for them.

During one of the exams, they shut off the lights early on them that had been grown with twelve-hour days and nights. Putting them into darkness after only an eight-hour day means they didn’t have time to store as much starch as usual. And this forced the plants to adjust their normal nightly rhythm.

Amazingly, even after this day length trick, the plants did very well in their exams and ended up with just five percent of starch left over at the end of the night. They had neither starved, nor stored starch that could have been used to fuel more growth.

The authors suggested that similar biological calculators may explain how a migratory bird, the little stint, can make a five-thousand-kilometer journey to their summer habitat in the Arctic and arrive with enough fat reserves to survive only approximately half a day more, on average.

The results of the study were published in e Life.