Posts Tagged ‘nap’

Teenagers and sleep. It’s certainly a passionate subject for many American parents … and those in China. University of Delaware’s Xiaopeng Ji is investigating the relationship between midday-napping behaviors and neurocognitive function in early adolescents. In a study funded by the National Institutes of Health, the School of Nursing assistant professor and principal investigator Jianghong Liu (University of Pennsylvania) turned to the Chinese classroom. With participants from schools in Jintan, she measured midday napping, nighttime sleep duration and sleep quality, and performance on multiple neurocognitive tasks.

Ji is interested in the relationship between sleep and cognition. Because of the intensive learning and education demands, the adolescent population is key. Neurocognitive functioning is essential for learning, emotion and behavior control. Her findings suggest that an association between habitual midday napping and neurocognitive function, especially in China, where midday napping is a cultural practice.

“Daytime napping is quite controversial in the United States. In Western culture, the monophasic sleep pattern is considered a marker of brain maturation,” Ji said. “In China, time for napping is built into the post-lunch schedule for many adults in work settings and students at schools.”

Ji has studied the circadian rhythm of sleep (a person’s 24-hour cycle). A developmental change takes place in circadian rhythm during adolescence; teenagers’ rhythm shifts one to two hours later than the preadolescent period.

“This phase delay is biologically driven in adolescents,” Ji said. “Think about that in a school schedule. Teenagers have to get up early for school. And, with this phase delay of going to bed later, they are at-risk for chronic sleep deprivation.”

Ji explained that these adolescents may experience impaired neurocognitive function, which makes paying attention in school even more difficult. Memory and reasoning ability also suffer.

A circadian dip occurs daily from 12 to 2 p.m. During that period, adolescents are more likely to fall asleep. In a U.S. school, a student does not have a formal opportunity to do so.

“Throughout childhood, U.S. kids experience decreases in napping tendencies. Kids are trained to remove their midday napping behavior,” said Ji. “Conversely in China, the school schedule allows children to maintain it.”

Researchers have taken a friend or foe mentality towards napping. Many consider a midday snooze as needed compensation for nighttime sleep deprivation; another faction believes daytime napping continually interferes with nighttime sleep. Many studies invite people to a lab setting — experimentally imposing the nap — and find the aforementioned cognitive benefits. But Ji said that’s difficult to correlate with habitual sleep at home.

“The results from lab studies may be different from what the population is habitually doing at home — sleeping in their own bed,” Ji said.

Lots of research exists on adults, but that’s not the case for adolescents. This lack of literature motivated Ji to take on the task. And since the American school schedule was a barrier to finding more information, researchers used Chinese data in the University of Delaware and University of Pennsylvania collaborative study.

Key findings

Ji investigated two dimensions of nap behavior — frequency and duration. Routine nappers, who napped five to seven days in a week, had sustained attention, better nonverbal reasoning ability and spatial memory. How long to nap is also an important question? The sweet spot is between 30 to 60 minutes. A nap longer than one hour interferes with circadian rhythm. Participants who slept between 30 to 60 minutes produced better accuracy in attention tasks as well as faster speed. She recommends not to nap after 4 p.m., nor over-nap.

Researchers were surprised to find a positive relationship between midday napping and nighttime sleep, which is different than the literature. Habitual nappers (who napped more often) tended to have a better nighttime sleep.

“That’s different than the findings in the United States, where napping may serve as a function to replace sleep lost from the previous night. Consequently, that may interfere with the following night’s sleep,” Ji said. “In China, a midday nap is considered a healthy lifestyle. Routine nappers are more likely to experience healthy nighttime sleep. So routine nappers are essentially trained to sleep well and sleep more at night.”

Ji was clear that this study was observational. At this point, she cannot conclude causality. She hopes this line of research can inform future studies and public health policy.

http://www.udel.edu/udaily/2018/april/xiaopeng-ji-napping-neurocognitive-function/

By Brigitte Steger

The Japanese don’t sleep. This is what everyone – the Japanese above all – say. It’s not true, of course. But as a cultural and sociological statement, it is very interesting.

I first encountered these intriguing attitudes to sleep during my first stay in Japan in the late 1980s. At that time Japan was at the peak of what became known as the Bubble Economy, a phase of extraordinary speculative boom. Daily life was correspondingly hectic. People filled their schedules with work and leisure appointments, and had hardly any time to sleep. The lifestyle of this era is aptly summed up by a wildly popular advertising slogan of the time, extolling the benefits of an energy drink. “Can you battle through 24 hours? / Businessman! Businessman! Japanese businessman!”

Many voiced the complaint: “We Japanese are crazy to work so much!” But in these complaints one detected a sense of pride at being more diligent and therefore morally superior to the rest of humanity. Yet, at the same time, I observed countless people dozing on underground trains during my daily commute. Some even slept while standing up, and no one appeared to be at all surprised by this.

I found this attitude contradictory. The positive image of the worker bee, who cuts back on sleep at night and frowns on sleeping late in the morning, seemed to be accompanied by an extensive tolerance of so-called ‘inemuri’ – napping on public transportation and during work meetings, classes and lectures. Women, men and children apparently had little inhibition about falling asleep when and wherever they felt like doing so.

If sleeping in a bed or a futon was considered a sign of laziness, then why wasn’t sleeping during an event or even at work considered an even greater expression of indolence? What sense did it make to allow children to stay up late at night to study if it meant that they would fall asleep during class the next day? These impressions and apparent contradictions led to my more intensive involvement with the theme of sleep for my PhD project several years later.

Initially, I had to fight against prejudice as people were reluctant to consider sleep a serious topic for academic enquiry. Of course, it was precisely such attitudes that had originally caught my attention. Sleep can be loaded with a variety of meanings and ideologies; analysing sleep arrangements and the discourse on it reveals attitudes and values embedded in the contexts in which sleep is organised and discussed. In my experience, it is the everyday and seemingly natural events upon which people generally do not reflect that reveal essential structures and values of a society.

We often assume that our ancestors went to bed ‘naturally’ when darkness fell and rose with the Sun. However, sleep times have never been such a simple matter, whether in Japan or elsewhere. Even before the invention of electric light, the documentary evidence shows that people were scolded for staying up late at night for chatting, drinking and other forms of pleasure. However, scholars – particularly young samurai – were considered highly virtuous if they interrupted their sleep to study, even though this practice may not have been very efficient as it required oil for their lamps and often resulted in them falling asleep during lectures.

Napping is hardly ever discussed in historical sources and seems to have been widely taken for granted. Falling asleep in public tends to be only mentioned when the nap is the source for a funny anecdote, such as when someone joins in with the wrong song at a ceremony, unaware that they have slept through most of it. People also seem to have enjoyed playing tricks on friends who had involuntarily dozed off.

Early rising, on the other hand, has clearly been promoted as a virtue, at least since the introduction of Confucianism and Buddhism. In antiquity, sources show a special concern for the work schedule of civil servants, but from the Middle Ages onwards, early rising was applied to all strata of society, with “going to bed late and rising early” used as a metaphor to describe a virtuous person.

Another interesting issue is co-sleeping. In Britain, parents are often told they should provide even babies with a separate room so that they can learn to be independent sleepers, thus establishing a regular sleep schedule. In Japan, by contrast, parents and doctors are adamant that co-sleeping with children until they are at least at school age will reassure them and help them develop into independent and socially stable adults.

Maybe this cultural norm helps Japanese people to sleep in the presence of others, even when they are adults – many Japanese say they often sleep better in company than alone. Such an effect could be observed in spring 2011 after the huge tsunami disaster destroyed several coastal towns. Survivors had to stay in evacuation shelters, where dozens or even hundreds of people shared the same living and sleeping space. Notwithstanding various conflicts and problems, survivors described how sharing a communal sleeping space provided some comfort and helped them to relax and regain their sleep rhythm.

However, this experience of sleeping in the presence of others as children is not sufficient on its own to explain the widespread tolerance of inemuri, especially at school and in the workplace. After some years of investigating this subject, I finally realised that on a certain level, inemuri is not considered sleep at all. Not only is it seen as being different from night-time sleep in bed, it is also viewed differently from taking an afternoon nap or power nap.

How can we make sense of this? The clue lies in the term itself, which is composed of two Chinese characters. ‘I’ which means ‘to be present’ in a situation that is not sleep and ‘nemuri’ which means ‘sleep’. Erving Goffman’s concept of “involvement within social situations” is useful I think in helping us grasp the social significance of inemuri and the rules surrounding it. Through our body language and verbal expressions we are involved to some extent in every situation in which we are present. We do, however, have the capacity to divide our attention into dominant and subordinate involvement.

In this context, inemuri can be seen as a subordinate involvement which can be indulged in as long as it does not disturb the social situation at hand – similar to daydreaming. Even though the sleeper might be mentally ‘away’, they have to be able to return to the social situation at hand when active contribution is required. They also have to maintain the impression of fitting in with the dominant involvement by means of body posture, body language, dress code and the like.

Inemuri in the workplace is a case in point. In principle, attentiveness and active participation are expected at work, and falling asleep creates the impression of lethargy and that a person is shirking their duties. However, it is also viewed as the result of work-related exhaustion. It may be excused by the fact that meetings are usually long and often involve simply listening to the chair’s reports. The effort made to attend is often valued more than what is actually achieved. As one informant told me: “We Japanese have the Olympic spirit – participating is what counts.”

Diligence, which is expressed by working long hours and giving one’s all, is highly valued as a positive moral trait in Japan. Someone who makes the effort to participate in a meeting despite being exhausted or ill demonstrates diligence, a sense of responsibility and their willingness to make a sacrifice. By overcoming physical weaknesses and needs, a person becomes morally and mentally fortified and is filled with positive energy. Such a person is considered reliable and will be promoted. If, in the end, they succumb to sleep due to exhaustion or a cold or another health problem, they can be excused and an “attack of the sleep demon” can be held responsible.

Moreover, modesty is also a highly valued virtue. Therefore, it is not possible to boast about one’s own diligence – and this creates the need for subtle methods to achieve social recognition. Since tiredness and illness are often viewed as the result of previous work efforts and diligence, inemuri – or even feigning inemuri by closing one’s eyes – can be employed as a sign that a person has been working hard but still has the strength and moral virtue necessary to keep themselves and their feelings under control.

Thus, the Japanese habit of inemuri does not necessarily reveal a tendency towards laziness. Instead, it is an informal feature of Japanese social life intended to ensure the performance of regular duties by offering a way of being temporarily ‘away’ within these duties. And so it is clear: the Japanese don’t sleep. They don’t nap. They do inemuri. It could not be more different.

http://www.bbc.com/future/story/20160506-the-japanese-art-of-not-sleeping