Why do we have to one-third of time spent sleeping life? -Sleep, sleep, memory-IT information

Studies have found that insomnia can lead to confusion of brain electrical activity of neurons, thus preventing memory writes.

Why we spent on sleep one-third time in one's life? Lack of scientific explanation of this problem so far, but about the sleepless nights of damage to brain research has brought us a glimmer of inspiration, but also for the potential treatment of depression offer exciting clues.

In a study published in August, the new, the researchers found for the first time, sleep resets the brain neurons in awake when a stable connection. This process is very important for memory and learning in the brain, which we have to adapt to the world around them.

Scientists have found that just one night of sleep loss is enough to block the brain's natural replacement system. Once deprived of their rest time, seems to occur over connections of neurons in the brain and electrical activity of brain disorders also occur that the new memory does not properly handle.

Germany Freiburg, a psychiatrist at the University of kelisituofu·nisen (Christoph Nissen) conducted the study, he for the study to help mentally ill patients was very excited by the potential. Radical therapy for major depression is one of the sleep deprivation, that is, do not put patients to sleep, Neeson think this treatment is through changes in patients with brain function. This new study provides a deeper understanding of this phenomenon, and has the potential to generate actual treatment.

"Why should humans sleep? This is a fundamental problem. Why are we such brain States spends so much time in my life? The study tells us that sleep is a highly active process of the brain, and not a waste of time. Healthy brain needs sleep. "Nissen said.

The study's results also support the synaptic equilibrium hypothesis of sleep (synaptic homeostasis hypothesis,SHY), this hypothesis was proposed by scientists at the University of Wisconsin-Madison in 2003. Our brains need a lot of information in a single day, whether it is the morning news, weather conditions, or chat after lunch and tea making needs of raw materials, and this theory can explain our brain absorbs a wide range of information in a day, why will need a rest.

SHY hypothesis is that, when we're in the waking state, as the learning process progresses, formation of neural connections in the brain synapses can be continually enhanced, eventually leading to the brain is full of all kinds of information. This process requires a lot of energy, while sleep brain activity leveled off, consolidate memories and be fully prepared for cycle the next morning.

In this article published in the nature newsletter (Nature Communications) journal papers, Nissen described a series of aged 19-25 years, 11 men and 9 women to participate in the test results, some of them after a good night's sleep, while others couldn't sleep at all the night before. In the sleepless nights, the participants can play games, take a walk, or cook food, but caffeine is not allowed. Researchers to full observation to make sure they stay awake.

In the first round of experiments, Nissen using magnetic pulses to activate the neurons in the brains of volunteers and raises his left hand twitching of the muscles. For volunteers with no sleep, very weak pulse is enough to trigger muscle movement. This shows that the sleep-deprived brain in a State of more exciting, and enjoy a good night's sleep than neuronal connections in the brain should also more closely.

Next, Nissen was another form of brain stimulation to simulate memory are written to the neuronal activation. He found that the sleep-deprived group of neurons respond more difficult, it also means that write to memory sleep loss caused by damage to the process.

In short, the results show that sleep can calm the brain activity in order to write to memory. In contrast, disorders of the sleep-deprived brain is interference from electrical activity in the brain, making it difficult to complete the memory function, and that this process was almost blocked. The consequences of sleep loss can be manifested through a simple memory test, test weary volunteers performed much worse than after rest of volunteers. However, how sleep affects the brain connection? Refined mechanism, you might want to answer "why are we sleeping" the issue itself is much more important. Understanding the mechanism, can help a lot to overcoming sleep problems night-shift workers and military personnel, develop new drugs or strategies to help them restore normal brain connections. In this study, the volunteers ' blood tests indicated that sleep deprivation reduces brain-derived neurotrophic factor (BDNF) levels, and that the regulation of synaptic connections in the brain.

But Nissen is more interested in the treatment of depression, this study helps scientists better understand sleep deprivation in the treatment and its effect on depression. "If you make a night without sleep in patients with major depression, about 60% people in the mood, motivation and cognitive functions show substantial improvement. We believe that it is because of this therapy in these patients can be converted to a more favourable status. "He said.

Although the effects of sleep deprivation therapy is very alarming, but many patients will relapse in the subsequent night's sleep, so it is not widely used. But Nissen thinks that's not the point. "It proves that we could in just a few hours to convert a different state of mind. Our idea was to use sleep and sleep deprivation to understanding the brain and the development of new treatment options. If you take antidepressants or psychotherapy, that might take weeks or months to see results. ”

Zhuliao·tuonuoni, Professor of sleep medicine at the University of Wisconsin-Madison (Giulio Tononi) is the first SHY hypothesis of the scientists, he believed that the new study "very subtle and powerful", and confirmed that at present can only be conducted in animal experiments.

"Sleep is critical is one of the main reasons, it makes your brain in the process of learning new things every day to store and consolidate the old memories," Tononi says, "learning and memory requires synaptic activity, which is energy consumption and very easy to reach saturation. During sleep, the brain can readjust days increased synaptic activity to normal levels. ”

Norway Oslo University psychologist Lars? Wesley (Lars Westlye) with "stunning" to praise the research, he said, the results can make the sleep biology, complex brain functions and links between many mental illnesses such as schizophrenia and depression. And Nissen, he agreed that clearer understanding of brain connections may explain the effect of sleep deprivation therapy in patients with depression in very significant reasons, and plans to study the efficacy of these patients.

"These new findings strongly encourage further research on patients, which can not only learn more about the root causes of disease, but also the development of new treatments. "Lal says.

为什么我们要把人生三分之一的时间花在睡觉上？ - 睡觉,睡眠,记忆 - IT资讯

研究发现，失眠会导致神经元脑电活动的混乱，从而妨碍记忆的写入。

为何我们把人生中三分之一的时间花在睡觉上？这个问题至今为止仍缺乏科学解释，但关于失眠的夜晚对大脑造成损害的研究却给我们带来了一丝启示，同时也为抑郁症的潜在治疗方法提供了令人兴奋的线索。

在8月新发表的一项研究中，研究人员首次发现，睡眠能够重置大脑在清醒时所构成稳定的神经元连接。这一过程对于大脑的记忆和学习而言十分重要，以此我们才能适应周遭世界。

科学家们发现，仅仅一个晚上的睡眠缺失就足以阻断大脑天然的重置机制。一旦被剥夺休息时间，大脑中的神经元似乎就会出现过度连接的状况，并且脑电活动也出现紊乱，以至于新产生的记忆不能得到恰当的处理。

德国弗莱堡大学的精神病学家克里斯托弗·尼森（Christoph Nissen）主持了这项研究，他对于这项研究帮助精神疾病患者的潜在功能感到十分激动。重性抑郁的根治疗法之一就是睡眠剥夺，也就是不让患者睡觉，尼森认为这种疗法是通过改变患者的大脑连接而发挥作用的。这项新研究为这一现象提供了更深层次的理解，并有可能产生更多实际的治疗方法。

“人类为什么要睡觉？这是个根本问题。为什么我们要为这种大脑状态花费生命中如此多的时间？这项研究告诉我们，睡眠是一段大脑高度活跃的过程，而且并非浪费时间。健康的大脑功能需要睡眠。”尼森说道。

这项研究的结果同时也佐证了睡眠的突触静态平衡假说（synaptic homeostasis hypothesis，SHY），这种假说是由威斯康辛大学麦迪逊分校的科学家在2003年提出的。我们的大脑在一天中需要接受诸多信息，无论是早间新闻、天气情况，还是午饭后的闲聊和泡茶需要的原料，而这一理论能够解释我们的大脑在吸收一天中各式各样的信息后为什么会需要休息。

SHY假说认为，当我们处于清醒状态时，随着学习过程的进行，形成大脑内神经元连接的突触能够得到不断地增强，最终令大脑中充满了各类信息。这一过程需要大量的能量，而睡眠则令大脑活动趋于平缓、巩固记忆并为第二天早上的循环往复做好充分准备。

在这篇发表于《自然·通讯》（Nature Communications）期刊的论文中，尼森描述了一系列由年龄在19到25岁之间的11名男性和9名女性参与的试验结果，他们中有的经历了一晚良好的睡眠，有的则前一晚都没有睡觉。在无眠的夜晚里，参与者们可以玩游戏、散步或烹饪食物，但不允许摄入咖啡因。研究人员对其进行全程观察以确保他们保持清醒。

在首轮实验中，尼森采用磁脉冲来激活自愿者大脑中的神经元并引发左手肌肉的抽搐。对于没有睡觉的自愿者，非常微弱的脉冲就已经足以引发肌肉的运动。这说明缺少睡眠的大脑处于一种更加兴奋的状态，与享受一晚良好的睡眠相比，大脑中神经元的连接程度也要更加紧密。

接下来，尼森进行了另一种形式的大脑刺激来模拟记忆被写入时神经元的激活方式。他发现，睡眠剥夺实验组的神经元更难发生响应，这也说明写入记忆过程会受到睡眠缺失所带来的损害。

总之，研究结果表明，睡眠能够令大脑的活动平静下来，以便写入记忆。与之相反，被剥夺睡眠的大脑会被紊乱的脑电活动所干扰，从而很难完成记忆功能，以至于这一过程几乎被阻断了。睡眠缺失的后果可以通过一个简单的记忆测试体现出来，测试中疲惫的志愿者们的表现要比经过充分休息的志愿者差得多。不过，睡眠到底是如何影响大脑连接的？提炼出其中的机制，可能要比回答“我们为什么要睡觉”这个问题本身重要得多。了解了这样的机制，就能帮助很多需要克服睡眠不足问题的夜班工人及军事人员，开发出新型药物或对策帮助他们恢复大脑的正常连接。在这个研究中，志愿者们的血样检测表明，睡眠不足降低了脑源性神经营养因子（BDNF）的水平，而这种分子能够调控大脑中的突触连接。

但尼森更感兴趣的是抑郁症治疗方面，这个研究帮助科学家更好地理解了睡眠剥夺治疗及其对抑郁症的疗效。“如果你让重性抑郁患者一晚上不睡觉，大约60%的患者都会在心情、动机和认知功能上表现出实质性的改善。我们认为，这是因为这种疗法可以将这些患者转换到一种更加有利的状态。”他说道。

尽管睡眠剥夺疗法的疗效十分惊人，但由于许多患者在随后的夜间睡眠中都会复发，所以其应用并不广泛。但尼森认为这不是重点。“它证明了我们有可能在短短几小时内转换一个人不同的心情状态。我们的想法就是利用睡眠和睡眠剥夺来理解大脑并开发新型治疗方案。如果采用抗抑郁药物或心理治疗，那可能需要几周或几个月才会看到疗效。”

威斯康辛大学麦迪逊分校的睡眠医学教授朱利奥·托诺尼（Giulio Tononi）是首位提出SHY假说的科学家，他认为这项新型研究“非常精妙且强大”，并且证实了目前只能在动物试验中进行的实验结果。

“睡眠至关重要的一个主要原因就是，它令大脑在每天学习新事物的过程中能够存储并巩固旧记忆，”托诺尼说道，“学习和记忆需要突触活动，这非常消耗能量并且很容易达到饱和。在睡眠过程中，大脑能够将白天逐渐增强的突触活动重新调节到正常水平。”

挪威奥斯陆大学的心理学家拉尔斯?韦斯利（Lars Westlye）用“精彩绝伦”来称赞这项研究，他表示，这项研究结果能够阐明睡眠生物学、复杂的大脑功能以及精神分裂症和抑郁症等诸多精神疾病间的联系。和尼森一样，他也认为对于大脑连接性的更清晰的理解可能会解释睡眠剥夺疗法在抑郁症患者中疗效十分显著的原因，并计划研究这些患者的疗效。

“这些新研究结果可以强有力地激励患者组的进一步研究，这不但可以进一步了解疾病的根源，同时还能开发新的治疗方式。”拉尔斯说道。