From Zzz to Aha!

When you are stuck on a problem, sometimes it is best to stop thinking about it — consciously, anyway. Research has shown that taking a break or a nap can help the brain create paths to a solution. Now a new study expands on the effect of this so-called incubation by using sound cues to focus the sleeping mind on a targeted problem.

When humans sleep, parts of the brain replay certain memories, strengthening and transforming them. About a decade ago researchers developed a technique, called targeted memory reactivation (再激活) (TMR), aimed at further strengthening selected memories: when a sound becomes associated with a memory and is later played during sleep, that memory gets reactivated.

In a study published last November in Psychological Science, scientists tested whether revisiting the memory of a puzzle during sleep might also improve problem-solving. About 60 participants visited the laboratory before and after a night of sleep. In an evening session, they attempted different puzzles, with a distinct music clip repeating in the background for each, until they had worked on 6 puzzles they could not solve. Overnight they wore electrodes (电极条) to detect slow-wave sleep, a state of deep dreamless sleep, which may be important for memory enhancement — and a device played the sounds related to 3 of the 6 unsolved puzzles. The next day, back at the lab, the participants attempted the 6 puzzles again. All told, the subjects solved 32% of the sound-cued puzzles compared with 21% of the untargeted puzzles— an increase of more than 50 percent.

“These are super cool results. Now we need to go further and try to understand them by firstly replicating (复制) them and secondly trying to work out the component processes that are actually being influenced,” says Penny Lewis, a psychologist at Cardiff University.

Beyond providing new evidence that humans restructure memories while sleeping, the research may have practical implications. In a futuristic world, maybe TMR could help us use sleep to work on our problems. Sleep-monitoring technology is increasingly accessible — and even without gadgets, prospective solvers can focus on important problems before bed.

Computing power of quantum (量子) machines is now still very low. Increasing it is still proving to be a major challenge. Physicists now present a new architecture for a universal (广泛适用的) quantum computer that overcomes such limitations and could be the basis of the next generation of quantum computers soon.

Quantum bits (qubits) (量子比特) in a quantum computer serve as a computing unit and memory at the same time. Because quantum information cannot be copied, it cannot be stored in a memory as in a classical computer. Due to this limitation, all qubits in a quantum computer must be able to interact (相互影响) with each other. This is now still a major challenge for building powerful quantum computers. In 2015, theoretical physicist Wolfgang Lechner, together with his team, solved this difficulty and suggested a new architecture for a quantum computer.

“This architecture was originally designed for making problems best. In the process, we reduced the architecture to a minimum,” recalls Lechner. “It means that not all qubits have to interact with each other anymore.” With his team, he has now found that this parity (奇偶) concept is also suitable for a universal quantum computer.

Parity computers can perform operations between two or more qubits on a single qubit. “Existing quantum computers already perform such operations very well on a small scale,” Michael Fellner from Lechner’s team explains. “However, as the number of qubits increases, it becomes more and more complex to perform these gate operations.” Scientists now show that parity computers can perform quantum Fourier transformations with significantly fewer computation steps and thus more quickly.

The new concept also offers hardware-efficient error correction. Because quantum systems are very sensitive to disturbances, quantum computers must correct errors continuously. Significant resources must be devoted to protecting quantum information, which greatly increases the number of qubits required. “Our model operates with a two-stage error correction. One type of error is prevented by the hardware used,” says Anette Messinger from Lechner’s team, “the other type of error can be detected and corrected via the software. This would allow a next generation of universal quantum computers to be realized with manageable effort.”

Nowadays, the world is slowly becoming a high-tech society and we are now surrounded by technology. Facebook and Twitter are innovative tools; text messaging is still a somewhat existing phenomenon and even e-mail is only a flashing spot on the screen when compared with our long history of snail mail. Now we adopt these tools to the point of essentialness, and only rarely consider how we are more fundamentally affected by them.

Social media, texting and e-mail all make it much easier to communicate, gather and pass information. But they also present some dangers. By removing any real human engagement, they enable us to develop our abnormal self-love without the risk of disapproval or criticism theatrical metaphor (隐喻), these new forms of communication provide a stage on which we create our own characters, hidden behind a fourth wall of tweets, status updates and texts. This unreal state of unconcern can become addictive as we separate ourselves a safe distance from the cruelty of our fleshly lives, where we are imperfect, powerless and insignificant. In essence, we have been provided not only the means to be more free, but also to become new, to create and protect a more perfect self to the world. As we become more reliant on these tools, they become more a part of our daily routine and so we become more restricted in this fantasy.

So it is that we live in a cold era, where names and faces represent two different levels of closeness, where working relationships occur only through the magic of email and where love can start or end by text message. An environment such as this reduces interpersonal relationships to mere digital exchanges.

Would a celebrity have been so daring to do something dishonorable if he had had to do it in person? Doubtful. It seems he might have been lost in a fantasy world that ultimately convinced himself into believing the digital self could obey different rules and regulations, as if he could continually push the limits of what’s acceptable without facing the consequences of “real life.”