要点：时间感知、记忆与专注力

欢迎来到《赫伯曼实验室精华》，我们将重温往期节目，为您带来最有效、最具实操性的基于科学的心理健康、身体健康与表现提升工具。我是安德鲁·赫伯曼，斯坦福医学院神经生物学与眼科学教授。今天我们要探讨的是时间感知。我们对时间的感知或许是衡量生命最重要的标尺，因为这种感知直接关联着调控情绪、压力、快乐、兴奋的神经化学状态，并从根本上塑造着我们评估过去的方式。

Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science based tools for mental health, physical health, and performance. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today, are talking about time perception. Our perception of time is perhaps the most important factor in how we gauge our life. And the reason for that is that our perception of time is directly linked to the neurochemical states that control mood, stress, happiness, excitement, and of course it frames the way in which we evaluate our past.

它框定了我们对当下的认知——判断自己是否走在正轨，也框定了我们对未来的预期。让我们深入探讨时间感知，其最基础的层面被称为'节律同步'。这是指你的内在生理与心理过程如何与外部事物相联结。而人类终生都无法摆脱的最基本同步形式，就是所谓的'年节律'。

It frames our present, whether or not we think we are on track or off track, and it frames our sense of the future. So let's talk about time perception. And the most fundamental aspect of time perception is something called entrainment. Entrainment is the way in which your internal processes, your biology and your psychology are linked to some external thing. And the most basic form of entrainment that we are all a slave to all year round for our entire life are so called circannual rhythms.

我们的眼睛、大脑和身体内存在专门记录时间流逝的神经元，就像体内内置的日历系统。其运作机制精妙而简洁：眼睛接收的光线会抑制大脑释放褪黑激素。这种激素有两大功能：促使夜间产生睡意，以及调节睾酮、雌激素等其他激素水平。

We have neurons, nerve cells in our eye, in our brain, and in our body that are marking off the passage of time throughout the year, literally a calendar system in your brain and body. And the way this works is beautifully simple. Light seen by your eyes inhibits, meaning it reduces the amount of a hormone released in your brain called melatonin. Melatonin has two major functions. One function is to make you sleepy at night and the other is to regulate some of the other hormones of the body, in particular testosterone and estrogen.

根据居住地不同，全年日照时长变化会导致接触阳光的总量差异。白昼较长时，体内褪黑激素分泌量通常较少；反之在短日照时期，褪黑激素的分泌量及持续时间都会显著增加。因此褪黑激素水平与日照时长直接相关。

Throughout the year, depending on where you live, day length varies. And as a consequence, the amount of light from the sun that is available to you varies. So when days are long, the amount of melatonin in your brain and body that's released tends to be less. When days are very short, the amount of melatonin that's released and the duration that that melatonin exists in your brain and body tends to be much longer. So melatonin correlates with day length.

接触更多光照时褪黑激素减少，光照不足时则增多。虽然每日光接触量不同，但人体具备精密机制来综合计算自然光与人造光源的暴露量。这个系统精确到令人惊叹——例如北半球春季的8小时白昼期间，随着日照逐渐延长，褪黑激素水平持续递减，这个信号会传遍全身系统，这就是多数人在春季精力更充沛的原因。反之冬季8小时白昼期间，对应褪黑激素水平却会逐日递增，原因何在？

And if we are viewing more light, we have less melatonin, we view less light, we have more melatonin. You see different amounts of light each day, but we have a process in our brain and body that averages the amount of light that you're seeing both from artificial sources and from sunlight and measures that off. And it's so exquisitely precise that for a given say eight hour day in the spring, because spring in the Northern Hemisphere or elsewhere, you know, days are getting longer, that means that the amount of melatonin is getting progressively less and less, and that signal is conveyed to all the systems of your brain and body. And this is why most people, not all, but most people feel like they have more energy in the spring. Conversely, when you have an eight hour day in the winter, the amount of melatonin that corresponds to that eight hour day is getting progressively greater and greater because why?

因为白昼日渐缩短，褪黑激素便日复一日增加。每个细胞和系统都对此作出响应，因此多数人在冬季会感到精力稍逊、情绪略低（当然存在例外）。褪黑激素信号就这样将你的内在状态——情绪、精力感、甚至食欲——与地球公转这个外部事件完美同步。还存在其他形式的节律同步，即你的身心与外部环境的其他匹配机制。

Days are getting shorter, so melatonin is increasing from day to day to day. Every cell and system of your body pays attention to this, and as a consequence, most people, not all, but most people feel they have a little less or sometimes a lot less energy and a slightly lower mood in the winter months. Now, there are exceptions to this, of course, but the melatonin signal is the way in which your internal state, your mood, your sense of energy, even your appetite is entrained, is matched to some external event. In this case, the event is the rotation of the earth around the sun. There are other forms of entrainment, meaning the matching of your brain and body to things that are happening in your external environment.

全年范围内，人类分泌的睾酮与雌激素会随日照变化——长日照期分泌量通常高于短日照期。下一个我们被同步的时间单元是'昼夜节律'，即24小时周期。这可能是人类最强大且无法逃避的生理节律。位于口腔上方的生物钟细胞会以极其规律的节奏向身心释放化学物质，自然形成了24小时周期中的清醒活跃期与睡眠期。

Across the calendar year, the amount of testosterone and estrogen that human beings make varies, such that in longer days, they tend to make more testosterone and estrogen than in shorter days. The next level of time or bin of time, as we say, that we are all entrained or matched to is the so called circadian time cycle, which is twenty four hour rhythm. This is perhaps the most powerful rhythm that we all contain and that none of us can escape from. We all have this circadian clock that resides over the roof of our mouth, the cells in that circadian clock fire, meaning they release chemicals into our brain and body on a very regular rhythm. Not surprisingly, there are periods of every twenty four hour cycle when we are very active and we tend to be alert and others when we are asleep.

我们拥有昼夜节律钟，它会周期性波动，每二十四小时升降一次并重复循环。我们身体的每个细胞中，各种基因的表达都呈现二十四小时的振荡规律。正如我们所说，这些节律被外界的光暗周期所同步——清晨阳光、黄昏阳光以及深夜的黑暗，确保我们大脑和身体细胞内发生的这些振荡变化与外界光暗周期保持一致。我必须再三强调，保持昼夜节律同步的精确性至关重要。为什么呢？

We have the circadian clock, it oscillates, it goes up and down once every twenty four hours and then repeats. Every cell of our body has a twenty four hour oscillation in the expression of various genes. They are entrained, as we say, to the outside light dark cycle because morning sunlight, evening sunlight, and the lack of light in the middle of the night, make sure that the changes, these oscillations that are occurring within the cells of our brain and body are matched to the outside light dark cycle. And I cannot emphasize enough how important it is that your circadian entrainment be precise. Why?

因为昼夜节律同步的紊乱会导致严重的健康问题。它会增加患癌风险，加剧肥胖问题，引发心理健康隐患，延缓伤口愈合，降低身心表现水平，还会扰乱荷尔蒙分泌。

Because disruptions in circadian entrainment cause huge health problems. They increase cancer risk. They increase obesity. They increase mental health issues. They decrease wound healing, they decrease physical and mental performance, they disrupt hormones.

你需要让自身细胞与外在的昼夜节律保持同步。而外在昼夜节律主要由阳光出现与消失的时段构成。这就是为什么从这场关于昼夜节律同步的讨论中，可以提炼出以下简单方案：在醒来后一小时内（假设你是清晨起床，尤其要如此）接触十到三十分钟的明亮光线，最好是阳光，到户外去晒太阳。然后在下午或傍晚时分再次进行，时长同样为十到三十分钟，具体取决于室外光线强度。

You want your cells to be linked to the circadian cycle that's outside you. And the circadian cycle outside you mainly consists of when there's sunlight and when there is not. And that's why the simple protocols to fall out of this whole discussion about circadian entrainment are the following. View ten to thirty minutes of bright light, ideally sunlight within an hour of waking, assuming that you're waking early in the day, especially you wake up early in the day, get outside, see sunlight. Do that again in the afternoon or around evening, ten to thirty minutes, depending on how bright it is outside.

本质上，你需要在白天通过眼睛接收尽可能多的明亮光线（理想来源是阳光）。而到了晚上，则要尽量减少进入眼睛的强光。还有其他方法可以所谓地校准你的生物钟，其中最有效的方式之一是在每天相对固定的时段进行体育活动。不必每天坚持，但如果要锻炼，尽量选择每天相近的时间。

Basically you want as much bright light, ideally from sunlight coming in through your eyes throughout the day. And then in the evening, you want as little bright light coming in through your eyes. There are other ways to so called entrain your circadian clock. One of the best ways to do that is to engage in physical activity at fairly regular times of day. You don't have to do it every day, but if you're going to exercise, try and exercise at a fairly consistent time of day.

当这个生物钟开始紊乱时会发生什么？毕竟本期主题是时间感知，而非昼夜节律与同步机制。1985年Ashoff进行的经典研究（现已被多次重复）发现：当人们进入没有钟表、窗户的环境，有时甚至处于持续黑暗或恒亮条件下——

What happens when this circadian clock starts getting disrupted? I mean, this is after all an episode about time perception. It's not an episode about circadian rhythms and entrainment. Well, there's a classic study by Ashoff done in 1985 that's now been repeated many times where they had people go into environments where they didn't have clocks and they didn't have windows and they didn't have watches. They were sometimes even in constant dark or constant light.

研究人员评估了人们对较短时间跨度的感知能力，结果非常有趣：人们会低估自己在这些封闭环境中度过的时间。比如经过42天后询问受试者，他们会回答28天或36天。

And they evaluated how well people perceive the passage of time on shorter timescales. And what they found was really interesting. What they found is that people underestimate how long they were in these isolated environments. So after forty two days or so, they'd ask people, how long do you think you've been in here? And people would say twenty eight days or thirty six days.

在缺乏钟表、阳光接触或规律人工光照的异常环境中，人们普遍低估了自己的停留时长。此外研究发现，他们对较短时间间隔的感知也严重紊乱。正常情况下人们能较准确估算两分钟（误差最多5-15秒），但当昼夜节律同步机制被破坏时，人们对分钟甚至秒级的时间感知会出现巨大偏差。

They generally underestimated how long they had been in this very odd environment with no clocks or watches or exposure to sunlight or regular rhythms of artificial light. In addition, they found that their perception of shorter time intervals was also really disrupted. So if they ask them to measure off two minutes, normally people are pretty good at measuring off two minutes. People come within, you know, five to fifteen seconds at most. Well, when people's circadian clocks or circadian entrainment, I should say, was disrupted, their perception of time measurement on shorter timescales of minutes or even seconds was greatly disrupted.

正如我们稍后将看到的，这实际上会给你应对工作、应对各类挑战带来巨大问题。你需要让自己的昼夜节律与外界光暗周期高度同步，这样你对较短时间间隔的感知才能精确。因为事实证明，准确感知特定任务或所参与事项的时间能力，是预测你表现优劣的最根本方式之一。我们早就知道有些方法可以改善睡眠，包括服用苏糖酸镁、茶氨酸、洋甘菊提取物和甘氨酸等成分，以及藏红花和缬草根等较冷门的物质。这些都是临床验证过的成分，能帮助你入睡、保持睡眠，并醒来时感觉更精神焕发。

And as we'll see in a couple of minutes, that actually causes great problems for how you contend with work, how you contend with challenges of different kinds. You want your circadian entrainment to be pretty locked in or pretty entrained to the outside light dark cycle so that your perception of time on shorter time intervals can be precise because the ability to perceive time accurately for the given task or given thing that you're involved in turns out to be one of the most fundamental ways that predicts how well or poorly you perform that thing or task. We've known for a long time that there are things that we can do to improve our sleep. And that includes things that we can take things like magnesium threonate, theanine, chamomile extract, and glycine, along with lesser known things like saffron and valerian root. These are all clinically supported ingredients that can help you fall asleep, stay asleep, and wake up feeling more refreshed.

我很兴奋地宣布，我们的长期赞助商AG1刚刚推出了一款名为AGZ的新产品——一种夜间饮品，旨在帮助你获得更好睡眠并醒来时感觉神清气爽。过去几年里，我与AG1团队合作研发了这个新配方。它含有最佳比例的助眠成分，只需简单冲泡即可饮用。这省去了在繁杂的助眠补充剂中筛选合适剂量和成分的所有麻烦。据我所知，AGZ是目前市场上最全面的睡眠补充剂。

I'm excited to share that our longtime sponsor AG1 just created a new product called AGZ, a nightly drink designed to help you get better sleep and have you wake up feeling super refreshed. Over the past few years, I've worked with the team at AG1 to help create this new AGZ formula. It has the best sleep supporting compounds in exactly the right ratios in one easy to drink mix. This removes all the complexity of trying to forge the vast landscape of supplements focused on sleep and figuring out the right dosages and which ones to take for you. AGZ is to my knowledge, the most comprehensive sleep supplement on the market.

我在睡前30到60分钟服用它——顺便说一句，味道很棒。它显著提升了我睡眠的质量和深度。这既来自我的主观感受，也通过睡眠监测数据得到验证。我期待大家都能尝试这款AGZ新配方，享受优质睡眠带来的益处。

I take it thirty to sixty minutes before sleep. It's delicious by the way. And it dramatically increases both the quality and the depth of my sleep. I know that both from my subjective experience of my sleep and because I track my sleep. I'm excited for everyone to try this new AGZ formulation and to enjoy the benefits of better sleep.

AGZ有巧克力、薄荷巧克力和混合莓果三种口味。正如我之前提到的，它们都非常美味。三者中我最喜欢薄荷巧克力，但其实每种都很棒。若想尝试AGZ，请访问drinkagz.com/huberman获取特别优惠。再次提醒，网址是drinkagz.com/huberman。

AGZ is available in chocolate, chocolate mint, and mixed berry flavors. And as I mentioned before, they're all extremely delicious. My favorite of the three has to be, I think chocolate mint, but I really liked them all. If you'd like to try AGZ, go to drinkagz.com/huberman to get a special offer. Again, that's drinkagz.com/huberman.

接下来我想谈谈所谓的超昼夜节律。超昼夜节律是指约90分钟的生理周期。我们的全部生命活动都被分割成这些90分钟的超昼夜周期。无论你夜间睡6小时、4小时、8小时还是10小时，整个睡眠过程都由这些90分钟周期构成。而早晨醒来后，你做的许多事同样受这些超昼夜节律支配。

Next, I'd like to talk about so called ultradian entrainment. Ultradian rhythms are rhythms of about ninety minutes or so. And all of our existence is broken up into these ninety minute ultradian cycles. When you go to sleep at night, whether or not you sleep six hours or four hours or eight hours or ten hours, that entire period of sleep is broken up into these ninety minute ultradian cycles. However, when you wake up in the morning, many of the things that you do are governed by these ultradian rhythms.

例如，90分钟的时间段似乎是大脑能够进入专注警觉状态、进行高强度工作的理想时长。约90分钟后，你从事这类脑力或体力工作的能力会显著下降。从自助类书籍到商业著作，再到大众心理学读物，都试图利用这种超昼夜周期，建议人们将困难任务限制在90分钟内完成。我也是这个观点的支持者——实际上我采用90分钟工作周期，认为这种方式极其有效。

For instance, the ninety minute time block seems to be the one in which the brain can enter a state of focus and alertness and do hard work and focus, focus, focus. And then at about ninety minutes, there's a significant drop in your ability to engage in this mental or physical work. Now, from the self help literature to the business literature, to the pop psychology literature has tried to leverage these ultradian cycles by saying, if you're going to do something hard and you want to focus on it, limit it to ninety minutes or less. And I am one of those people who's also joined that conversation. And indeed I use ninety minute work cycles and I think they are extremely powerful.

虽然这本身不算是时间感知，但它再次体现了节律同步现象。我们同步于什么？在这个案例中，你同步的是特定神经化学物质的释放——主要是乙酰胆碱和多巴胺，它们让大脑能保持约90分钟的专注。约90分钟后，这些物质的释放量会急剧下降，导致专注力减退。常有人问我：如何确定90分钟周期起点？比如早上8点醒来刚结束一个睡眠周期，是否意味着下个可用于工作的周期从8:01就开始了？

While this isn't time perception per se, it is again, an example of entrainment. What are we in training to? Well, what you're in training to is the release of particular neurochemicals, in this case, acetylcholine and dopamine that allow your brain to focus for particular periods of time, ninety minutes or so, and after about ninety minutes or so, the amount of those chemicals that can be released tends to drop very low, which is why your ability to focus becomes diminished. I always get the question, how do you know when the ninety minute cycle begins? In other words, let's say you wake up at 8AM and you just finished a ninety minute sleep cycle, does that mean that your next ninety minute cycle where you could do work begins right at 08:01?

不。关于这些基本休息活动周期，即超昼夜节律，有趣的是你可以随时启动它们。你可以设定一个时钟并决定，好，现在开始专注，现在开始工作，这九十分钟周期就是我要工作的时间段。然而你无法协商的是，大约一百分钟或一百二十分钟后，无论你是谁，你的表现都会下降。你将无法像之前那样专注。

No. The interesting thing about these basic rest activity cycles, these ultradian rhythms, is that you can initiate them whenever you want. You can set a clock and decide, okay, now the focus begins, now the work begins, and this ninety minute cycle is the period in which I'm going to do work. What you can't negotiate however, is that at about a hundred minutes or one hundred and twenty minutes, no matter who you are, you're going to see a diminishment in performance. You're not going to focus as well.

这再次是因为这些九十分钟周期与释放乙酰胆碱、多巴胺以及某种程度上去甲肾上腺素的神经元能力相关联，这些物质赋予我们高度专注、动机和驱动力，而这些周期正是通过这些神经回路发挥作用。大约九十分钟后，这些回路的活跃度会大幅降低，因此要继续保持高度专注就变得困难得多。有些人喜欢一天进行多个九十分钟的专注周期。这种情况下，你需要将它们分开。你不能连续进行一个又一个的九十分钟周期。

And that's again, because of the way that these ninety minute cycles are linked to the ability of the neurons that release acetylcholine and dopamine, and to some extent norepinephrine, the things that give us narrow focus, motivation, and drive, the way that these ninety minute cycles are involved in those circuits. After about ninety minutes, those circuits are far less willing to engage and therefore it's much harder to continue to focus to a high degree. Some people like to do multiple ninety minute cycles per day of focus. In that case, you need to separate them out. You can't do one ninety minute cycle then go right into another ninety minute cycle, another ninety minute cycle.

遗憾的是，你无法欺骗这些与乙酰胆碱、多巴胺和去甲肾上腺素相关的神经回路。对我来说，我可以在上午进行一个周期，下午可能再进行一个。这不是那种像查看电子邮件、发短信或刷社交媒体之类的工作。这是需要高度专注的艰苦工作，是解决各种难题的过程，这对每个人来说都会有所不同。

You can't cheat these circuits related to acetylcholine and dopamine and norepinephrine, unfortunately. For me, I can do one mid morning and probably do another one in the afternoon. This is not the kind of work that's like checking email or text messaging or social media. This is very focused hard work. It's working on hard problems of various kinds, and this will be different for everybody.

所以我建议它们之间至少间隔两到四个小时。大多数人可能一天最多只能应付两个周期。也许有些异于常人的人能做到三四个，但这种情况极其罕见。我认为即使一天一个周期也会感觉是相当大的精神投入，之后你会感到相当疲惫。现在我们讨论了年节律、昼夜节律和超昼夜节律，但还没有真正讨论时间感知本身。

So I recommend that they be spaced by at least two to four hours. And most people probably won't be able to handle more than two per day. There are probably some mutants out there that could do three or four, but that's exceedingly rare. I think even one a day is going to feel like a significant mental investment and afterwards you're going to feel pretty taxed. So now we've talked about circannual, circadian and ultradian rhythms, but we haven't really talked about time perception per se.

我们主要讨论了潜意识中缓慢振荡的方式，通过这些方式我们被调整以适应一年或一天，以及这些我们可以施加于工作上的超昼夜周期，如果我们愿意，可以利用它们来提高专注力。但关于时间本身的感知呢？究竟是什么控制着我们感知时间流逝的快慢？基本上有三种时间感知形式我们都应该了解。一种是我们对当下时间流逝的感知，即事情发生对我们来说显得有多快或多慢。

We've mainly talked about the subconscious, slow oscillatory ways in which we are entrained or matched to the year or to the day, and these ultradian cycles that we can impose on our work and that we can leverage toward more focus if we like. But what about the actual perception of time? What actually controls how fast or how slowly we perceive time going by? There are basically three forms of time perception that we should all be aware of. One is our perception of the passage of time in the present, how quickly or slowly things seem to be happening for us.

这有点像间隔计时器在滴答作响。滴答，滴答，滴答，要么像那样精细分割，要么滴答，滴答，滴答。我们有间隔计时器。我会讨论这些间隔计时器的基础。我们还参与所谓的预期计时，这就像秒表一样，随着事情向前发展进行测量。

This is kind of like an interval timer ticking off time. Tick, tick, tick, It's either fine slicing like that or tick, tick, tick. We have interval timers. I'll discuss the basis of those interval timers. We also engage in what's called prospective timing, which is like a stopwatch, measuring off things as they go forward.

这听起来可能有点像我刚才描述的，但实际上有点不同。例如，如果我让你开始测量未来两分钟的时间间隔，你可以做得很好。但如果我让你测量未来五分钟的时间间隔，而且你不能使用任何钟表、手表或手机之类的工具，你就必须设定刻度。你必须决定在这五分钟的时间块内你要计数多少次。还有回顾性时间，这是你如何测量过去的时间。

That might sound a little bit like what I just described, but it's actually a little bit different. For instance, if I told you to start measuring off a two minute time interval into the future, you could do that pretty well. But if I told you you had to measure a five minute time interval into the future and you couldn't use any clocks or watches or your phone or anything like that, you would have to set the tick marks. You would have to decide how many times you were going to count off during that five minute time block. There's also retrospective time, which is how you measure off time in the past.

所以如果我说，比如上周，我知道你去了公园，和朋友做了一些事，晚上还外出聚餐，那么午餐和晚餐之间隔了多久？你可能会想，我记得七点吃的晚餐，午餐大概在两点左右。你正在用记忆重构过去的事件序列，感知它们在时间中的相对位置，对吧？我们既有对过去时间间隔的回顾性测量，也有对未来时间的预期性测量。人类神经系统对时间感知的美妙之处在于，它归根结底由几种简单分子调控——这些分子决定了我们是精细切割时间，还是将时间打包成更大的区块。

So if I say, you know, last week, I know you went to the park, you did some things with friends, you know, you went out in the evening, how long was it between lunch and when you went to dinner with friends? You probably think, okay, well, I remember I went to dinner at seven and we had lunch right around two. You're using memory to reconstruct certain sets of events in the past and get a sense of their relative positioning within time, okay? So we have retrospective, current time interval measurements, and then a prospective time measurement into the future. The beauty of time perception in the human nervous system is that it boils down to a couple of simple molecules that govern whether or not we are fine slicing time or whether or not we are batching time in larger bins.

这些分子你可能听说过，比如多巴胺、去甲肾上腺素，它们被称为神经调质，因为能调节其他神经回路的工作方式。还有血清素等物质。血清素与多巴胺和去甲肾上腺素在大脑中的释放部位不同，对时间感知的影响也不同。举个多巴胺和血清素如何调节时间感知的例子，我想引用一些已在动物和人类身上得到验证的研究——这些研究表明，大脑释放的多巴胺越多，我们越容易高估已流逝的时间。让我再强调一次。

Those molecules go by names that maybe you've heard things like dopamine and norepinephrine, neuromodulators called neuromodulators because they modulate, they change the way that other neural circuits work. Also things like serotonin. Serotonin is released from a different site in the brain than dopamine and norepinephrine is, and has a different effect on time perception. So just to give you an example of how things like dopamine and serotonin can modulate our perception of time, I want to focus on a little bit of literature that now has been done fortunately in animals and humans, and which essentially shows that the more dopamine that's released into our brain, the more we tend to overestimate the amount of time that has just passed. Let me repeat that.

大脑中释放的多巴胺越多，我们越倾向于高估时间的流逝量。这些实验设计非常直接（抱歉），且具有高度客观性：给受试者或动物服用增加多巴胺的药物后，让他们在不借助钟表的情况下判断一分钟何时结束。随着大脑多巴胺水平升高，人们往往在38秒时就认为一分钟到了——他们明显高估了实际经过的时间。

The more dopamine that is released into our brain, the more we tend to overestimate how much time has passed. These experiments are very straightforward, excuse me, and they're very objective, which is really nice, which is you can give people or an animal a drug that increases the amount of dopamine and then ask them to measure off without any measurement device like a watch or a clock when one minute has passed. As dopamine levels rise in the brain, people tend to think that the minute is up before a minute. So at the thirty eight second mark, they'll say, okay, think a minute up. So they've overestimated how much time has passed, okay?

多巴胺水平越高，人们的高估倾向越明显。而去甲肾上腺素（又称正肾上腺素）的作用与多巴胺非常相似。相反，神经调质血清素会让人低估时间流逝量。这非常有趣——不仅展示了药理学如何调节时间感知，也与昼夜节律密切相关。

The higher the level of dopamine, the more people tend to overestimate. Now it's also true that norepinephrine, also called noradrenaline, plays a role and its role is very similar to that of dopamine. Conversely, the neuromodulator serotonin causes people to underestimate the amount of time that's passed. So this is very interesting. It's interesting in terms of how pharmacology can be used to adjust time perception, but it's also interesting in the context of that circadian rhythm.

新证据表明，在24小时周期内，大脑、血液和身体中的多巴胺、去甲肾上腺素与血清素含量会随昼夜节律剧烈波动。大量数据指向一个事实：在 circadian 周期的前半段（约上午时段），多巴胺和去甲肾上腺素水平远高于血清素；而在后半段（特别是傍晚至夜间），血清素水平开始上升。这意味着我们对时间流逝的感知在昼夜两个阶段会有显著差异——这对规划每日日程至关重要，毕竟大家都在思考如何安排全天任务。

There's some emerging evidence that throughout the twenty four hour cycle, there are robust changes in the amount of dopamine, norepinephrine, and serotonin that are present in the brain and bloodstream and body, depending on time of day within the circadian cycle. So much of the evidence points to the fact that in the first half of the day, approximate first half of the day, dopamine and norepinephrine are elevated in the brain, body and bloodstream much more than is serotonin. And that in the second half of the day, and in particular towards evening and nighttime, serotonin levels are going up. What that means is that our perception of the passage of time will be very different in the early part of the day and in the latter half of the day. Now, is important in terms of how one thinks about structuring their day, because I know many people are thinking about the various tasks that they need to do throughout their day.

所有关于工作效率的文献（至少我查阅过的）都指出：我们应该把最困难、最不想做或最重要的任务放在早晨完成，这既是心理策略，也能带来成就感。坦白说，我认为这个方案非常棒。顺便补充一点支持性证据（同时也回归昼夜节律的核心作用）：当睡眠被剥夺、碎片化或长期低质量时，最先出现的就是多巴胺能、去甲肾上腺素能和血清素能系统的昼夜调节紊乱。多巴胺和去甲肾上腺素对时间感知的影响有时会带来破坏性甚至适应不良的结果，最典型的例子就是创伤经历。

Many, or I should say all of the literature, at least that I can find on productivity and things of that sort point to the idea that we should be doing the hardest task, the thing that we want to do the least or the most important task early in the day as a kind of a psychological tool for getting it done and feeling as if we accomplished something. And I think that's an excellent protocol, frankly. And as an aside, to support what I said, but also to take us back to this critical role of the circadian rhythm, there is a lot of evidence that when one's sleep is disrupted, when sleep is either too short or is fragmented or is not of high enough quality for enough days, one of the first things to happen is that there is a dysregulation of these dopaminergic, noradrenergic, and serotonergic states throughout the day. Now there is a version of how dopamine and norepinephrine can impact our perception of the passage of time in ways that can be very disruptive or even maladaptive. And the best example that I'm aware of is trauma.

许多车祸或其他重大创伤的幸存者会出现「超频」现象。当事件发生时，多巴胺和去甲肾上腺素水平激增，导致我们对时间的「帧率」感知急剧升高——仿佛一切都在超慢速运动。这看似不全是坏事，但问题在于这种记忆的编码方式：涉及海马体和新皮层的记忆系统本质上是时空记录仪。什么是时空记录仪？

Many people who have been in car accidents or who have experienced some other form of major trauma do what's called overclocking. Overclocking is when levels of dopamine and norepinephrine increase so much during a particular event that we find slice, in other words, the frame rate is increased so much so that we perceive things as happening in ultra slow motion. Now that might not seem like a bad thing overall, but the problem with overclocking is the way in which that information gets stamped down into the memory system. So the memory system, which involves areas of the brain like the hippocampus, but also the neocortex is basically a space time recorder. What do I mean by space time recorder?

当然，你的神经系统位于头骨的黑暗之中。它对外界知之甚少，除了通过眼睛进入的光线、耳朵接收的声波以及皮肤接触等。因此，它必须接收所有这些神经信号，并创建事件的记录。它不会记录所有发生的事，但车祸、创伤这类事件往往会被铭刻在我们的记忆里。所谓‘铭刻’，实际上是指反映某些事件的神经元精确放电序列。

Well, your nervous system of course is housed in the darkness of your skull. It doesn't have a whole lot of information about the outside world, except light coming in through the eyes and whatever happens to hit our ears in terms of sound waves and skin and so forth. So it has to take all those neural signals and it has to create a record of what happened. Now it doesn't create a record of everything that happened, but car accidents and trauma and things of that sort oftentimes are stamped down into our record of what happened. And what gets stamped down, what we actually mean by the phrase stamped down is that the precise firing of the sequence of neurons that reflected some events.

假设我遭遇车祸，特定的神经元会因为车辆翻滚、尖叫声、血迹等而激活。所有这些神经活动在海马体中重复，同时这些神经元的放电序列也被记住。所以不仅是神经元按一、二、三、四的顺序放电，还包括它们以特定速率放电。实际事件中是一、二、三、四的顺序，记忆则存储为这些神经元按一、二、三、四放电的模式，对吧？

So let's say I'm in a car accident, certain neurons are firing because of the flipping of the car or there's screams or there's blood or things of that sort. All of that neural activity gets repeated in the hippocampus, and then the sequence of the firing of those neurons is also remembered. So it's not just that neuron one, two, three, four fired in that sequence. It's also that neuron one, two, three, four fired at a particular rate. So it would be one, two, three, four during the actual event, and then the memory is stored as firing of those neurons as one, two, three, four, right?

如果事件发生时神经元以一、二、三、四的速率放电，记忆存储就不会简单重复这个序列。换句话说，既有‘空间编码’——特定神经元的激活很重要，也有‘速率编码’——神经元放电的速度或相对时序同样是记忆的一部分。这赋予记忆系统极大的灵活性。意味着你可以用海马体中同一组神经元，通过调整不同神经元的放电速率组合来存储更多记忆。否则，若每个记忆都需要不同神经元组，我们就需要巨大的海马体和头颅了。

If during the event it was one, two, three, four at that rate, the storage of the memory is not going to be one, two, three, four, okay? In other words, there's both a space code as we say, meaning the particular neurons that fire is important, and there's a rate code, how quickly those neurons fire or the relative firing, the timing of the firing of those neurons is also part of the memory. This affords our memory system tremendous flexibility. What it means is that you can take the same set of neurons in the hippocampus and stamp down many, many more memories because all you have to do is use a match of the different rates of the different neurons that we're firing in order to set that code, right? Otherwise, if you needed a different set of neurons for every memory, you need an enormous hippocampus, you need an enormous head.

我想你已经理解了基本概念。‘超频’是指帧率过高导致记忆被深刻铭刻，人们很难摆脱这种记忆及其相关情绪。事实上，创伤受害者首先认识到的是他们不会忘记发生的事情。理想情况下，通过良好治疗，最终体验的情感重量将与记忆本身分离。可能有人会问：为什么创伤期间会释放多巴胺？

So I think you get the basic idea. Overclocking is a case in which the frame rate is so high that a memory gets stamped down and people have a very hard time shaking that memory and the emotions associated with that memory. In fact, one of the first things that trauma victims learn is that they aren't going to forget what happened. What's eventually going to happen ideally with good treatment is that the emotional weight of the experience will eventually be divorced from the memory of the experience. Some of you are probably saying why dopamine during trauma?

我曾以为多巴胺是快乐分子。实际上，它不一定是奖励分子，而是动机、追求和驱动的分子。由于多巴胺与去甲肾上腺素的密切关系，它们常共同释放。我们不确定车祸等创伤中是否释放多巴胺。

I thought dopamine was the feel good molecule. Well, in reality, dopamine is not necessarily a molecule of reward. It's a molecule of motivation, pursuit and drive. And because of the close relationship between dopamine and norepinephrine, oftentimes they are co released. So whether or not dopamine is released during car crashes or other forms of trauma, we don't know.

但我们确知的是，多巴胺系统和去甲肾上腺素系统（后者即去甲肾上腺素）在唤醒状态增强时会大幅活跃。唤醒可具负价（关联于我们厌恶的事件），也可具正价。但多巴胺和去甲肾上腺素是所有高唤醒状态的共同标志。这就是为什么我们看到多巴胺与时间感知变化（无论积极还是消极事件）相关的证据。现在我要短暂休息，感谢我们的赞助商BetterHelp。

But what we do know is that both the dopamine system and noradrenergic system, when we say noradrenergic, we mean norepinephrine, those systems are greatly increased anytime there's a heightened state of arousal. And arousal can have negative valence, meaning associated with an event that we really hate, that we would prefer not to be involved in, or it can have positive valence. But dopamine and norepinephrine are kind of the common hallmark of all things of elevated arousal. And so that's why we see evidence for dopamine being associated with these changes in time perception, both for positive events and for negative events. I'd like to take a quick break and acknowledge one of our sponsors, BetterHelp.

BetterHelp提供完全在线进行的专业治疗服务。我坚持每周治疗已超三十年。最初是学校留校条件所迫，但很快意识到治疗对整体健康至关重要。事实上，我认为定期治疗与每周锻炼同等重要——当然我也坚持锻炼。

BetterHelp offers professional therapy with a licensed therapist carried out entirely online. I've been doing weekly therapy for well over thirty years. Initially, didn't have a choice. It was a condition of being allowed to stay in school, but pretty soon I realized that therapy is an extremely important component to overall health. In fact, I consider doing regular therapy just as important as getting regular exercise, which of course I also do every week.

优质的心理治疗本质上提供三方面的价值。首先，它能建立与可信任之人的良好关系，你可以与之讨论所有关心的问题。其次，它能以情感支持或定向指导的形式提供帮助。第三，专业治疗能带来有价值的洞见。通过BetterHelp平台，你可以轻松找到与你契合的专业治疗师，获得有效治疗带来的这些益处。

There are essentially three things that great therapy provides. First of all, it provides a good rapport with somebody that you can trust and talk to about all issues that you're concerned about. Second of all, it can provide support in the form of emotional support or directed guidance. And third, expert therapy can provide useful insights. With BetterHelp, they make it very easy to find an expert therapist with whom you resonate with and can provide those benefits that come through effective therapy.

此外，由于BetterHelp支持全程在线治疗，时间效率极高。它能轻松融入繁忙的日程，无需通勤前往治疗师办公室或在候诊室等待。你只需上线就能进行咨询。若想尝试BetterHelp，请访问betterhelp.com/huberman，首月可享九折优惠。

Also because BetterHelp allows therapy to be done entirely online, it's very time efficient. It's easy to fit into a busy schedule. There's no commuting to a therapist's office or sitting in a waiting room or anything like that. You simply go online and hold your appointment. If you would like to try BetterHelp, go to betterhelp.com/huberman to get 10% off your first month.

再次重申：betterhelp.com/huberman。到目前为止，我一直在讨论多巴胺和部分血清素如何差异化影响你对当下事件快慢的感知。但请记住，我们同时拥有预期时间、当下体验时间和回溯时间。精彩的研究表明，多巴胺状态不仅改变当下的体验方式，还会改变我们对过去事件的记忆方式及其发生速率——且这两个方向是相反的。

Again, that's betterhelp.com/huberman. Now, up until now, I've been talking about how dopamine and to some extent serotonin can differentially impact your perception of how fast or how slowly things are happening in the moment. But remember, we have prospective time, we have our experience of time in the moment, and we have retrospective time. And there are beautiful studies that have showed that the dopaminergic state changes the way, not just that we experience things now, but that it changes the way in which we remember things in the past and the rate at which those things occurred. And those are in opposite direction.

简而言之，当你经历有趣或多样化（包含多种元素）的事情时——即大脑多巴胺水平升高时——你会感觉时间飞逝。想象孩子在游乐园的奇妙一天：他们体验无数新鲜事物，兴奋不已，感觉时光飞驰。但事后回忆时，却会觉得那是充满无数事件的漫长一天。这就形成了我们对当下有趣、刺激、多样化事件的感知与事后记忆之间的悖论关系。

So to make this very simple, if something that you experience is fun or varied, meaning it has a lot of different components in it, and in other words, is associated with an increase in dopamine in your brain, you will experience that as going by very fast. Imagine an amazing day for a kid at an amusement park. They can do a ton of things, it's all new, they're very excited and they'll feel like it goes by very fast. But later, they will remember that experience as being very long, that it was a long day full of many, many events. And so there's this paradoxical relationship between how we perceive fun, exciting, varied events in the present and how we remember them in the past.

有过度假经历的人会发现，当度过精彩的假期时，整体感觉时光飞逝。假期最后一天你会感叹：哇，过得真快！因为发生了太多事情。但6-8个月后回忆时，却会觉得：哇，那是段好长的时光，我们做了这个，又做了那个...记忆中的时间总比实际体验更绵长。

For those of you who've gone on vacation, if you've had an amazing day on vacation, it'll seem like, an amazing vacation overall, it will seem like it goes by very fast. The last day of vacation, you sort of go, woah, it went by so fast because there's so much happening. But in memory, six to eight months later, you remember, wow, that just went, that was a long, long thing. We had this, then we had that, then we did this, then we had that. It tends to spool out in a longer memory than the actual experience.

相反，当你感到无聊或厌恶某事时，当下会觉得时间难熬。但回溯时，那段时光在记忆中却显得短暂。我提及这些是因为：驱动我们的不仅是昼夜节律钟、年节律钟和超昼夜节律钟，还有这些随兴奋程度变化的计时器——而决定这种变化的正是多巴胺和血清素等神经调节物质。

Conversely, if you're bored with something or it's something you really don't like, it's going to seem like it takes a long time to go through that experience in the moment. But retroactively looking back, it will seem like that moment was very short. And so the reason I bring this up is we aren't just driven by these circadian clocks and these circannual clocks and these ultradian clocks. We are driven by these timers that vary depending on our level of excitement. And they vary depending on our level of excitement because of these neuromodulators, dopamine and serotonin.

我喜欢这样理解：你拥有两块秒表。一块是多巴胺秒表，它以毫秒为单位精密切片，像高分辨率摄像机般记录体验。另一块则收集大时间单元，表针以更大间隔跳动标记时间。根据你是兴奋还是无聊，你会启用不同的时间秒表，从而产生不同的时间感知。

So the way I like to think about it is that you have two clocks, two stopwatches. One is a dopaminergic stopwatch that find slices really closely. It's like counts off milliseconds and it's grabbing a movie of your experience at very high resolution. And then the other hand, have a stopwatch that's gathering big time bins, big ticks along the hand is moving at bigger intervals, marking off time. And depending on whether or not you're excited or whether or not you're bored, you're using different stopwatches on time and therefore you're perceiving your differently.

多巴胺等神经调节物质与新奇感如何影响时间感知和记忆的一个非常有趣的方面，在于我们如何看待自身与地点及人物的关系。有研究文献明确指出，在一个地方经历的新奇体验越多，我们不仅会觉得自己更熟悉那个地方，还会感觉在那里度过的时间比实际更长。这里有个思维实验可以说明文献中的观点：假设我搬到纽约市——我个人确实很喜欢纽约。

One very interesting aspect to the way that neuromodulators like dopamine and novelty interact with time perception and memory is how we perceive our relationship to places and people. So really interesting literature showing that the more novel experiences we have in a place, the more we feel we know that place obviously, but the longer we feel we've been there. So here's the kind of Gedunken or thought experiment that illustrates what's in the literature. Let's say I were to move to New York City. I happen to really like New York City.

虽然从未在那里生活过，但假设我住了一年。在这个思想实验中，如果我经历了100次不同的新鲜刺激体验，一年后我会感觉自己确实在那里生活了一年。但如果在纽约换了三个住处，结识了三倍的人，获得三倍的新奇体验，我的主观感受会是居住时间远超实际。这种现象在社交互动中同样成立。

I've never lived there, but let's say I lived there. I lived in a given apartment for a year and I would have a number of different experiences in this mental experiment, let's say I had a 100 different exciting and new experiences. I would, at the end of that year, feel as if I lived there a certain period of time, one year, I would actually know I lived there one year. If however I lived in three different places in New York City and I met three times as many people and I had three times as many novel experiences, I would actually feel as if I had been there much longer than had I only lived in one location. This is also true for social interactions.

当与某人共同经历多个新环境时，我们会产生更深刻的相互了解感。这揭示了多巴胺如同大脑中的弹性货币——它在我们期待之事成真时释放，也在意外发生时涌现（即便是负面意外）。但更引人深思的是它与时间感知的关联。

When we move to multiple or several novel environments with somebody else, we tend to feel as if we know that person much better and that they know us much better. Now that's all very interesting and speaks to the fact that dopamine is a kind of flexible currency in the brain. It's doled out, if you will, or released when something that one hopes will happen happens. And it's released when there's a surprise, even if it's negative surprise, it's not something that the subject wanted to happen. But the more interesting thing is how that relates to time perception.

关键在于：多巴胺的释放频率和时机实际上设定了我们对所有事物的感知'帧率'，不仅限于积极或消极事件。多巴胺对时间感知的这种支配性影响，指向一个清晰、可操作且强大的工具——习惯。虽然习惯在各种语境下被讨论过，但从多巴胺奖励与时间感知的角度看，在一天中特定间隔安排习惯性routine，不仅能有效调动多巴胺系统，更能将每天划分为一系列我称之为'功能单元'的模块。

What I mean is how often and when you release dopamine is actually setting the frame rate on the entire perception of everything, not just for positive events or negative events. This governance over our perception of time that dopamine has points to a very clear, very actionable and very powerful tool. And that is a tool that many people have talked about before, which are habits. People have discussed habits in a variety of contexts, but in the context of dopamine reward and time perception, what this means is that placing specific habitual routines at particular intervals throughout your day is a very, not just convenient, but a very good way to incorporate the dopamine system so that you divide your day into a series of what I would call functional units. What would this look like?

比如晨起后固定进行某个触发多巴胺释放的习惯。这不仅能带来愉悦感（多巴胺确实能激发动力），更重要的是它标记了某个时间段的开始。随后在早餐等节点插入其他习惯行为——无需严格精确时间，但保持规律序列——这种方式不仅能获得多巴胺相关的奖励和动力，更会成为我们划分全天体验的框架。

It would mean waking up and having one specific habit that you always engage in that causes a release of dopamine. You could say, well, great, that'll make me feel good. And I would agree, dopamine release generally makes us feel motivated, but it would have an additional effect of marking that time of day as the beginning of a particular time bin. Then inserting another habit, perhaps the beginning of, I don't know, your breakfast or something, but recognizing that that's a habit and being fairly habitual. You don't have to be obsessively precise about the timing, but that regular sequencing of things is going to lead not just to dopamine release as it relates to reward and motivation and feeling good, but it actually becomes the way in which we carve up our entire experience of our day.

今天我们探讨了时间感知的诸多方面（虽未穷尽所有），包括神经同步、多巴胺的作用、习惯以及为特定目标调整时间感的各类方法。若想深入了解，我推荐Dean Bornemano教授的杰作《你的大脑是时间机器：时间神经科学与物理学》，这位UCLA教授是该领域的世界级权威。

Today, we covered a lot about time perception. We certainly didn't cover everything about time perception, but we covered things like entrainment, the role of dopamine, habits, and various routines that can adjust your sense of time for sake of particular goals. If you're interested in learning more about time perception, I'd like to point you to a really excellent book called Your Brain Is a Time Machine, The Neuroscience and Physics of Time. The book was written by professor Doctor. Dean Bornemano, who's a professor at UCLA and a world expert in the neuroscience and physics of time.

感谢您今天的宝贵时间与专注聆听。最后同样重要的是，感谢您对科学的热情。

Thank you for your time and attention today. And last, but certainly not least, thank you for your interest in science.