Hundreds of years ago, Charles Darwin predicted that facial expressions of emotion are 【小题1】. If you’ve ever seen an episode of the popular US TV drama Lie To Me, you will really understand facial expressions. The leading actor of the show, Dr. Cal Lightman has spent 20 years studying nonverbal communication and facial expressions, which allows him to point out other people’s studying nonverbal communication and facial expressions which allows him to point out other people’s 【小题2】 and on many occasions, to be skilled at tricking in order to get the truth.

Is there really much truth behind this science of 【小题3】 human emotions through expressions? Paul Ekman, a(n) 【小题4】 psychologist whose work focuses on mapping facial expressions, is Lie To Me’s scientific advisor and the following are some of his explanations.

Each micro-expression is unique to 【小题5】 specific emotions because the person is often unaware of doing it. But it doesn’t necessarily mean that they are lying when someone uses a hand to hide part of his face. The person could be holding back information but you may better consider looking at other more important clues rather than just the simple hand-to-face gesture.

People look away when they are thinking carefully and considering each word before it is spoken, not just when they are 【小题6】 an excuse. Oblique eyebrows are a very reliable 【小题7】of sadness and few people can make this 【小题8】 expression, so it is actually never faked.

Lightman often uses the guilty knowledge technique, mentioning something that only the guilty person will know about and show a(n)【小题10】. This is often used in polygraph exams: “Was the person strangled, shot or stabbed to death?” Only the killer knows and is likely to respond physiologically when the actual weapon is mentioned.

A failed study, a happy accident and a promising treatment for blindness In the textbooks, science is simple. You come up with an idea, put it to the test, and then accept it or reject it depending on what your experiments reveal. In the real world, though, things are rarely that straightforward, as a paper just published in Science Translational Medicine shows.

The disease in question is Leber hereditary optic neuropathy (LHON). A defective gene in a patient’s mitochondria — the tiny structures that provide a cell’s energy — causes retinal cells to die. That leads to sudden and rapid loss of sight, with many 【小题1】 becoming legally blind within a year. It affects between one in 30,000 and one in 50,000 people. Men in their 20s and 30s are particularly susceptible. Treatment is limited and not quite effective.

Since most cases are caused by a mutation (突变) in a single gene, LHON is a good 【小题2】 for gene therapy, a form of genetic engineering which aims to replace the defective gene with a working one. With that in mind, Dr Yu-Wai-Man, an ophthalmologist at Cambridge University, and his colleagues loaded up a (an) 【小题3】 virus with a corrected copy of the gene and injected it into their patients’ eyes.

Many viruses can insert their genes into the DNA of their hosts. That is 【小题4】 a bad thing, because cells so subverted (破坏) produce more copies of the virus. In this case, the hope was that infection would be a good thing. The defanged virus could not 【小题5】. But it was capable of replacing the damaged gene with a working copy.

Most medical studies make use of a control group, against which the 【小题6】 of the treatment can be measured. Here, the researchers controlled the experiment by injecting only one of each patient’s eyes - chosen at random - with the virus. The other eye was given a sham injection, in which a syringe (注射器) was 【小题7】 against the eyes, but nothing came out of it. Using two eyes in the same patient makes for a perfect control: their genetic make-up is 【小题8】, and any confusing lifestyle factors are removed from the equation.

The researchers had hoped to see a big improvement in the treated eyes, compared with the untreated ones. They did not, and for that reason the study failed in its primary objective. Instead, in more than three-quarters of their patients, they saw substantial 【小题9】 in both eyes.

On the face of it, that was bizarre. Only one eye had received the treatment, after all. The virus, it seems, had found a way to travel from one eye to the other, probably via the optic nerve. Although it had a happy outcome in this case, the prospect of a gene-therapy virus travelling to places it is not intended to go might worry regulators.

And, though the study was 【小题10】 a failure, its practical success means that an effective treatment for LHON may at last be in reach. GenSight Biologics, the company that has developed the treatment, has already sent its results to Europe’s medical regulator. It hopes to hear back by the end of 2021.

Jenny Carter an NHS coordinator is an “extreme night owl,” one of an estimated 8.2% of the population whose natural inclination(倾向)is to fall asleep well after midnight. Left to her own devices, she’d prefer to go to bed around 3 a.m. and wake up about noon.

Why do night owls exist? There is no single 【小题1】 accepted theory, but evolutionary biologists think that communities with more variation in chronotypes(睡眠类型)may have been more likely to survive.

Another theory is that variation is 【小题2】 how genetics works. Right from birth, our personal biological clocks are already 【小题3】. Genetics establishes a person’s chronotype. Colin Espie, professor of sleep medicine at the University of Oxford, says this 【小题4】 differences in hair eye and skin color or height.

Natural night owls are 【小题5】 different from insomniacs or people who stay up until the early hours because of family or work circumstances. Being a night owl isn’t a problem.

But this isn’t always well understood. Jessica Batchelor is a medical writer who feels most productive at 11 p.m. “I can’t tell anyone when I went to sleep, woke up, showered or ate a meal without being 【小题6】,” she says “I struggle with feelings of guilt and shame.”

This mentality is rooted in our agrarian(耕地的)past when farm work had to begin at dawn.

Our culture mistakenly associates sleeping little and rising early with 【小题7】. It is often extolled(颂扬)as a habit of successful people: for instance in the 【小题8】 with Margaret Thatcher’s four-hour rest, or articles about “sleepless-elite” CEOs who start their days with a 4 a.m. jog.

Actually, there is nothing wrong with staying up late as long as you’re getting a good amount of sleep every night; 【小题9】, early risers have no special biological advantage. What research has not disproved, however, is that morning people tend to get more done.

The productivity expert Laura Vanderkam 【小题10】 that people should consider switching their schedule not because it’s necessarily better but because it’s practical.

Waking up earlier to work out, make headway on a creative project or enjoy a stress-free cup of coffee can help make it easier to accomplish more without sacrificing time for yourself.