ted演讲（8篇）
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ted演讲稿【第一篇】
亲爱的同学们：
大家好！
今天我国旗下演讲的题目是《健康饮食从我做起》。
每一家的健康与食品息息相关，随着经济社会不断进步，人们饮食文化日益多样化，食品卫生与安全成为备受关注的话题。
要健康饮食，就要做到以下几点：
1.不购买街边小吃或街边小店的垃圾食品，去一些正规超市购买食物。
2.买所需食品时，要注意生产日期、保质期、QS生产许可标志等等。
3.认准品牌购买，尽量买一些有品牌的食品。
4.少吃油炸食品及零食，多吃蔬菜水果等有营养的食品。
5.不买价格明显过低的食品，不要贪小失大。
注意以上几点，就大致能做到安全饮食了。俗话说：“民以食为天”。说得通俗一点就是人们每天要吃和喝，食物是人类赖以生存的物质。食品的质量决定了人类生命的质量。因此，食品必须是安全的并且有益健康的。
同时，也呼吁食品安全，关系你我他，但愿生产者不再为食品安全脸红，国人不再为食品安全担心，国家不再为食品安全丢脸。现在，让我们一起行动起来，杜绝有害食品，倡导绿色食品！希望同学们听了我这次的讲话后都健康饮食，健康地成长。
谢谢大家！
ted演讲稿【第二篇】
try something new for 30 days 小计划帮你实现大目标
a few years ago, i felt like i was stuck in a rut, so i decided to followin the footsteps of the great american philosopher, morgan spurlock, and trysomething new for 30 days. the idea is actually pretty simple. think aboutsomething you’ve always wanted to add to your life and try it for the ne_t 30days. it turns out, 30 days is just about the right amount of time to add a newhabit or subtract a habit — like watching the news — from your life.
几年前， 我感觉对老一套感到枯燥乏味，所以我决定追随伟大的美国哲学家摩根·斯普尔洛克的脚步，尝试做新事情30天。这个想法的确是非常简单。考虑下，你常想在你生命中做的一些事情 接下来30天尝试做这些。这就是，30天刚好是这么一段合适的时间 去养成一个新的习惯或者改掉一个习惯——例如看新闻——在你生活中。
there’s a few things i learned while doing these 30-day challenges. thefirst was, instead of the months flying by, forgotten, the time was much morememorable. this was part of a challenge i did to take a picture everyday for amonth. and i remember e_actly where i was and what i was doing that day. i alsonoticed that as i started to do more and harder 30-day challenges, myself-confidence grew. i went from desk-dwelling computer nerd to the kind of guywho bikes to work — for fun. even last year, i ended up hiking up , the highest mountain in africa. i would never have been thatadventurous before i started my 30-day challenges.
当我在30天做这些挑战性事情时，我学到以下一些事。第一件事是，取代了飞逝而过易被遗忘的岁月的是这段时间非常的更加令人难忘。挑战的一部分是要一个月内每天我要去拍摄一张照片。我清楚地记得那一天我所处的位置我都在干什么。我也注意到随着我开始做更多的，更难的30天里具有挑战性的事时，我自信心也增强了。我从一个台式计算机宅男极客变成了一个爱骑自行车去工作的人——为了玩乐。甚至去年，我完成了在非洲最高山峰乞力马扎罗山的远足。在我开始这30天做挑战性的事之前我从来没有这样热爱冒险过。
i also figured out that if you really want something badly enough, you cando anything for 30 days. have you ever wanted to write a novel? every november,tens of thousands of people try to write their own 50,000 word novel fromscratch in 30 days. it turns out, all you have to do is write 1,667 words a dayfor a month. so i did. by the way, the secret is not to go to sleep until you’vewritten your words for the day. you might be sleep-deprived, but you’ll finishyour novel. now is my book the ne_t great american novel? no. i wrote it in amonth. it’s awful. but for the rest of my life, if i meet john hodgman at a tedparty, i don’t have to say, “i’m a computer scientist.” no, no, if i want to ican say, “i’m a novelist.”
我也认识到如果你真想一些槽糕透顶的事，你可以在30天里做这些事。你曾想写小说吗？每年11月，数以万计的人们在30天里，从零起点尝试写他们自己的5万字小说。这结果就是，你所要去做的事就是每天写1667个字要写一个月。所以我做到了。顺便说一下，秘密在于除非在一天里你已经写完了1667个字，要不你就甭想睡觉。你可能被剥夺睡眠，但你将会完成你的小说。那么我写的书会是下一部伟大的美国小说吗？不是的。我在一个月内写完它。它看上去太可怕了。但在我的余生，如果我在一个ted聚会上遇见约翰·霍奇曼，我不必开口说，“我是一个电脑科学家。”不，不会的，如果我愿意我可以说，“我是一个小说家。”
(laughter)
(笑声)
so here’s one last thing i’d like to mention. i learned that when i madesmall, sustainable changes, things i could keep doing, they were more likely tostick. there’s nothing wrong with big, crazy challenges. in fact, they’re a tonof fun. but they’re less likely to stick. when i gave up sugar for 30 days, day31 looked like this.
我这儿想提的最后一件事。当我做些小的、持续性的变化，我可以不断尝试做的事时，我学到我可以把它们更容易地坚持做下来。这和又大又疯狂的具有挑战性的事情无关。事实上，它们的乐趣无穷。但是，它们就不太可能坚持做下来。当我在30天里拒绝吃糖果，31天后看上去就像这样。
(laughter)
(笑声)
so here’s my question to you: what are you waiting for? i guarantee you thene_t 30 days are going to pass whether you like it or not, so why not thinkabout something you have always wanted to try and give it a shot for the ne_t 30days.
所以我给大家提的问题是：大家还在等什么呀？我保准大家在未来的30天定会经历你喜欢或者不喜欢的事，那么为什么不考虑一些你常想做的尝试并在未来30天里试试给自己一个机会。
thanks.
谢谢。
(applause)
(掌声)
ted演讲稿【第三篇】
敬爱的老师，亲爱的同学：
每一天清晨太阳都会从东边升起，到了傍晚就会从西边落下，这个没有任何一个人能够改变，同样我们没法让时间停止，也没不可能让别人怎摸样，唯一能改变的，仅有自己！
小的时候，我总会问别人这样一个问题：你觉得我好不好，那莫在你心中我排第几呢？尤其是对自己亲近的人，如果他们的回答让我不高兴的话，我总会很生气很生气，下意识的觉得他们不喜欢我，所以就拼命的让他们改变看法，谁出我满意的答案！并且让他们都也必须要为我而改变，否则我会很难过的！
此刻想起来的确是可笑至极了，可是在今日我仍会向好朋友问这样的问题。
可是初中毕竟不是以前了，渐渐的我和身边的同学变得很疏远，无论是男生还是女生，无论是班里的同学还是年级里面的，关系都不是很好，那种感觉真的好难受，我想哭，可是却不敢。
我不明白为什末，我无力去对别人说你应当，你必须之类的话了。
不明白为什末，一霎那间我忽然懂得了什莫，我想要求自己做些深末。可能是因为此刻的环境吧，我不再在乎别人的看法，只做自己而已。
我以往无数次的想过要改变自己，可是好像都失败了，我不想明白原因，只想做我自己，所以此刻的我不再在乎别人的看法，已经不再在乎很多事情了，我不明白这算不算改变，如果是的话，那末是变好还是坏！
可是我清楚的体会到此刻的生活比以前简便很多，趣味很多。
是啊，即使很多人都认为江山易改本性难移，可是改变自己还是比改变别人要容易得多吖！
ted演讲稿【第四篇】
when i was seven years old and my sister was just five years old, we wereplaying on top of a bunk bed. i was two years older than my sister at the time-- i mean, i'm two years older than her now -- but at the time it meant she hadto do everything that i wanted to do, and i wanted to play war. so we were up ontop of our bunk beds. and on one side of the bunk bed, i had put out all of joe soldiers and weaponry. and on the other side were all my sister's mylittle ponies ready for a cavalry charge.
there are differing accounts of what actually happened that afternoon, butsince my sister is not here with us today, let me tell you the true story --(laughter) -- which is my sister's a little bit on the clumsy side. somehow,without any help or push from her older brother at all, suddenly amy disappearedoff of the top of the bunk bed and landed with this crash on the floor. now inervously peered over the side of the bed to see what had befallen my fallensister and saw that she had landed painfully on her hands and knees on all fourson the ground.
i was nervous because my parents had charged me with making sure that mysister and i played as safely and as quietly as possible. and seeing as how ihad accidentally broken amy's arm just one week before ... (laughter) ...heroically pushing her out of the way of an oncoming imaginary sniper bullet,(laughter) for which i have yet to be thanked, i was trying as hard as i could-- she didn't even see it coming -- i was trying as hard as i could to be on mybest behavior.
and i saw my sister's face, this wail of pain and suffering and surprisethreatening to erupt from her mouth and threatening to wake my parents from thelong winter's nap for which they had settled. so i did the only thing my littlefrantic seven year-old brain could think to do to avert this tragedy. and if youhave children, you've seen this hundreds of times before. i said, "amy, amy,wait. don't cry. don't cry. did you see how you landed? no human lands on allfours like that. amy, i think this means you're a unicorn."
(laughter)
now that was cheating, because there was nothing in the world my sisterwould want more than not to be amy the hurt five year-old little sister, but amythe special unicorn. of course, this was an option that was open to her brain atno point in the past. and you could see how my poor, manipulated sister facedconflict, as her little brain attempted to devote resources to feeling the painand suffering and surprise she just e_perienced, or contemplating her new-foundidentity as a unicorn. and the latter won out. instead of crying, instead ofceasing our play, instead of waking my parents, with all the negativeconsequences that would have ensued for me, instead a smile spread across herface and she scrambled right back up onto the bunk bed with all the grace of ababy unicorn ... (laughter) ... with one broken leg.
what we stumbled across at this tender age of just five and seven -- we hadno idea at the time -- was something that was going be at the vanguard of ascientific revolution occurring two decades later in the way that we look at thehuman brain. what we had stumbled across is something called positivepsychology, which is the reason that i'm here today and the reason that i wakeup every morning.
when i first started talking about this research outside of academia, outwith companies and schools, the very first thing they said to never do is tostart your talk with a graph. the very first thing i want to do is start my talkwith a graph. this graph looks boring, but this graph is the reason i gete_cited and wake up every morning. and this graph doesn't even mean anything;it's fake data. what we found is --
(laughter)
if i got this data back studying you here in the room, i would be thrilled,because there's very clearly a trend that's going on there, and that means thati can get published, which is all that really matters. the fact that there's oneweird red dot that's up above the curve, there's one weirdo in the room -- iknow who you are, i saw you earlier -- that's no problem. that's no problem, asmost of you know, because i can just delete that dot. i can delete that dotbecause that's clearly a measurement error. and we know that's a measurementerror because it's messing up my data.
so one of the very first things we teach people in economics and statisticsand business and psychology courses is how, in a statistically valid way, do weeliminate the weirdos. how do we eliminate the outliers so we can find the lineof best fit? which is fantastic if i'm trying to find out how many advil theaverage person should be taking -- two. but if i'm interested in potential, ifi'm interested in your potential, or for happiness or productivity or energy orcreativity, what we're doing is we're creating the cult of the average withscience.
if i asked a question like, "how fast can a child learn how to read in aclassroom?" scientists change the answer to "how fast does the average childlearn how to read in that classroom?" and then we tailor the class right towardsthe average. now if you fall below the average on this curve, then psychologistsget thrilled, because that means you're either depressed or you have a disorder,or hopefully both. we're hoping for both because our business model is, if youcome into a therapy session with one problem, we want to make sure you leaveknowing you have 10, so you keep coming back over and over again. we'll go backinto your childhood if necessary, but eventually what we want to do is make younormal again. but normal is merely average.
and what i posit and what positive psychology posits is that if we studywhat is merely average, we will remain merely average. then instead of deletingthose positive outliers, what i intentionally do is come into a population likethis one and say, why? why is it that some of you are so high above the curve interms of your intellectual ability, athletic ability, musical ability,creativity, energy levels, your resiliency in the face of challenge, your senseof humor? whatever it is, instead of deleting you, what i want to do is studyyou. because maybe we can glean information -- not just how to move people up tothe average, but how we can move the entire average up in our companies andschools worldwide.
the reason this graph is important to me is, when i turn on the news, itseems like the majority of the information is not positive, in fact it'snegative. most of it's about murder, corruption, diseases, natural very quickly, my brain starts to think that's the accurate ratio of negativeto positive in the world. what that's doing is creating something called themedical school syndrome -- which, if you know people who've been to medicalschool, during the first year of medical training, as you read through a list ofall the symptoms and diseases that could happen, suddenly you realize you haveall of them.
i have a brother in-law named bobo -- which is a whole other story. bobomarried amy the unicorn. bobo called me on the phone from yale medical school,and bobo said, "shawn, i have leprosy." (laughter) which, even at yale, ise_traordinarily rare. but i had no idea how to console poor bobo because he hadjust gotten over an entire week of menopause.
(laughter)
see what we're finding is it's not necessarily the reality that shapes us,but the lens through which your brain views the world that shapes your if we can change the lens, not only can we change your happiness, we canchange every single educational and business outcome at the same time.
when i applied to harvard, i applied on a dare. i didn't e_pect to get in,and my family had no money for college. when i got a military scholarship twoweeks later, they allowed me to go. suddenly, something that wasn't even apossibility became a reality. when i went there, i assumed everyone else wouldsee it as a privilege as well, that they'd be e_cited to be there. even ifyou're in a classroom full of people smarter than you, you'd be happy just to bein that classroom, which is what i felt. but what i found there is, while somepeople e_perience that, when i graduated after my four years and then spent thene_t eight years living in the dorms with the students -- harvard asked me to; iwasn't that guy. (laughter) i was an officer of harvard to counsel studentsthrough the difficult four years. and what i found in my research and myteaching is that these students, no matter how happy they were with theiroriginal success of getting into the school, two weeks later their brains werefocused, not on the privilege of being there, nor on their philosophy or theirphysics. their brain was focused on the competition, the workload, the hassles,the stresses, the complaints.
when i first went in there, i walked into the freshmen dining hall, whichis where my friends from waco, te_as, which is where i grew up -- i know some ofyou have heard of it. when they'd come to visit me, they'd look around, they'dsay, "this freshman dining hall looks like something out of hogwart's from themovie "harry potter," which it does. this is hogwart's from the movie "harrypotter" and that's harvard. and when they see this, they say, "shawn, why do youwaste your time studying happiness at harvard? seriously, what does a harvardstudent possibly have to be unhappy about?"
embedded within that question is the key to understanding the science ofhappiness. because what that question assumes is that our e_ternal world ispredictive of our happiness levels, when in reality, if i know everything aboutyour e_ternal world, i can only predict 10 percent of your long-term percent of your long-term happiness is predicted not by the e_ternal world,but by the way your brain processes the world. and if we change it, if we changeour formula for happiness and success, what we can do is change the way that wecan then affect reality. what we found is that only 25 percent of job successesare predicted by 75 percent of job successes are predicted by your optimismlevels, your social support and your ability to see stress as a challengeinstead of as a threat.
i talked to a boarding school up in new england, probably the mostprestigious boarding school, and they said, "we already know that. so everyyear, instead of just teaching our students, we also have a wellness week. andwe're so e_cited. monday night we have the world's leading e_pert coming in tospeak about adolescent depression. tuesday night it's school violence andbullying. wednesday night is eating disorders. thursday night is elicit druguse. and friday night we're trying to decide between risky se_ or happiness."(laughter) i said, "that's most people's friday nights." (laughter) (applause)which i'm glad you liked, but they did not like that at all. silence on thephone. and into the silence, i said, "i'd be happy to speak at your school, butjust so you know, that's not a wellness week, that's a sickness week. whatyou've done is you've outlined all the negative things that can happen, but nottalked about the positive."
the absence of disease is not health. here's how we get to health: we needto reverse the formula for happiness and success. in the last three years, i'vetraveled to 45 different countries, working with schools and companies in themidst of an economic downturn. and what i found is that most companies andschools follow a formula for success, which is this: if i work harder, i'll bemore successful. and if i'm more successful, then i'll be happier. thatundergirds most of our parenting styles, our managing styles, the way that wemotivate our behavior.
and the problem is it's scientifically broken and backwards for tworeasons. first, every time your brain has a success, you just changed thegoalpost of what success looked like. you got good grades, now you have to getbetter grades, you got into a good school and after you get into a betterschool, you got a good job, now you have to get a better job, you hit your salestarget, we're going to change your sales target. and if happiness is on theopposite side of success, your brain never gets there. what we've done is we'vepushed happiness over the cognitive horizon as a society. and that's because wethink we have to be successful, then we'll be happier.
but the real problem is our brains work in the opposite order. if you canraise somebody's level of positivity in the present, then their braine_periences what we now call a happiness advantage, which is your brain atpositive performs significantly better than it does at negative, neutral orstressed. your intelligence rises, your creativity rises, your energy levelsrise. in fact, what we've found is that every single business outcome brain at positive is 31 percent more productive than your brain atnegative, neutral or stressed. you're 37 percent better at sales. doctors are 19percent faster, more accurate at coming up with the correct diagnosis whenpositive instead of negative, neutral or stressed. which means we can reversethe formula. if we can find a way of becoming positive in the present, then ourbrains work even more successfully as we're able to work harder, faster and moreintelligently.
what we need to be able to do is to reverse this formula so we can start tosee what our brains are actually capable of. because dopamine, which floods intoyour system when you're positive, has two functions. not only does it make youhappier, it turns on all of the learning centers in your brain allowing you toadapt to the world in a different way.
we've found that there are ways that you can train your brain to be able tobecome more positive. in just a two-minute span of time done for 21 days in arow, we can actually rewire your brain, allowing your brain to actually workmore optimistically and more successfully. we've done these things in researchnow in every single company that i've worked with, getting them to write downthree new things that they're grateful for for 21 days in a row, three newthings each day. and at the end of that, their brain starts to retain a patternof scanning the world, not for the negative, but for the positive first.
journaling about one positive e_perience you've had over the past 24 hoursallows your brain to relive it. e_ercise teaches your brain that your behaviormatters. we find that meditation allows your brain to get over the cultural adhdthat we've been creating by trying to do multiple tasks at once and allows ourbrains to focus on the task at hand. and finally, random acts of kindness areconscious acts of kindness. we get people, when they open up their inbo_, towrite one positive email praising or thanking somebody in their social supportnetwork.
and by doing these activities and by training your brain just like we trainour bodies, what we've found is we can reverse the formula for happiness andsuccess, and in doing so, not only create ripples of positivity, but create areal revolution.
thank you very much.
(applause)
经典TED英语演讲稿【第五篇】
What I'd like to do today is talk about one of my favorite subjects, and that is the neuroscience of sleep.
Now, there is a sound -- (Alarm clock) -- aah, it worked -- a sound that is desperately, desperately familiar to most of us, and of course it's the sound of the alarm clock. And what that truly ghastly, awful sound does is stop the single most important behavioral experience that we have, and that's sleep. If you're an average sort of person, 36 percent of your life will be spent asleep, which means that if you live to 90, then 32 years will have been spent entirely asleep.
Now what that 32 years is telling us is that sleep at some level is important. And yet, for most of us, we don't give sleep a second thought. We throw it away. We really just don't think about sleep. And so what I'd like to do today is change your views, change your ideas and your thoughts about sleep. And the journey that I want to take you on, we need to start by going back in time.
"Enjoy the honey-heavy dew of slumber." Any ideas who said that? Shakespeare's Julius Caesar. Yes, let me give you a few more quotes. "O sleep, O gentle sleep, nature's soft nurse, how have I frighted thee?" Shakespeare again, from -- I won't say it -- the Scottish play. [Correction: Henry IV, Part 2] (Laughter) From the same time: "Sleep is the golden chain that ties health and our bodies together." Extremely prophetic, by Thomas Dekker, another Elizabethan dramatist.
But if we jump forward 400 years, the tone about sleep changes somewhat. This is from Thomas Edison, from the beginning of the 20th century. "Sleep is a criminal waste of time and a heritage from our cave days." Bang. (Laughter) And if we also jump into the 1980s, some of you may remember that Margaret Thatcher was reported to have said, "Sleep is for wimps." And of course the infamous -- what was his name? -- the infamous Gordon Gekko from "Wall Street" said, "Money never sleeps."
What do we do in the 20th century about sleep? Well, of course, we use Thomas Edison's light bulb to invade the night, and we occupied the dark, and in the process of this occupation, we've treated sleep as an illness, almost. We've treated it as an enemy. At most now, I suppose, we tolerate the need for sleep, and at worst perhaps many of us think of sleep as an illness that needs some sort of a cure. And our ignorance about sleep is really quite profound.
Why is it? Why do we abandon sleep in our thoughts? Well, it's because you don't do anything much while you're asleep, it seems. You don't eat. You don't drink. And you don't have sex. Well, most of us anyway. And so therefore it's -- Sorry. It's a complete waste of time, right? Wrong. Actually, sleep is an incredibly important part of our biology, and neuroscientists are beginning to explain why it's so very important. So let's move to the brain.
Now, here we have a brain. This is donated by a social scientist, and they said they didn't know what it was, or indeed how to use it, so -- (Laughter) Sorry. So I borrowed it. I don't think they noticed. Okay. (Laughter)
The point I'm trying to make is that when you're asleep, this thing doesn't shut down. In fact, some areas of the brain are actually more active during the sleep state than during the wake state. The other thing that's really important about sleep is that it doesn't arise from a single structure within the brain, but is to some extent a network property, and if we flip the brain on its back -- I love this little bit of spinal cord here -- this bit here is the hypothalamus, and right under there is a whole raft of interesting structures, not least the biological clock. The biological clock tells us when it's good to be up, when it's good to be asleep, and what that structure does is interact with a whole raft of other areas within the hypothalamus, the lateral hypothalamus, the ventrolateral preoptic nuclei. All of those combine, and they send projections down to the brain stem here. The brain stem then projects forward and bathes the cortex, this wonderfully wrinkly bit over here, with neurotransmitters that keep us awake and essentially provide us with our consciousness. So sleep arises from a whole raft of different interactions within the brain, and essentially, sleep is turned on and off as a result of a range of
Okay. So where have we got to? We've said that sleep is complicated and it takes 32 years of our life. But what I haven't explained is what sleep is about. So why do we sleep? And it won't surprise any of you that, of course, the scientists, we don't have a consensus. There are dozens of different ideas about why we sleep, and I'm going to outline three of those.
The first is sort of the restoration idea, and it's somewhat intuitive. Essentially, all the stuff we've burned up during the day, we restore, we replace, we rebuild during the night. And indeed, as an explanation, it goes back to Aristotle, so that's, what, 2,300 years ago. It's gone in and out of fashion. It's fashionable at the moment because what's been shown is that within the brain, a whole raft of genes have been shown to be turned on only during sleep, and those genes are associated with restoration and metabolic pathways. So there's good evidence for the whole restoration hypothesis.
What about energy conservation? Again, perhaps intuitive. You essentially sleep to save calories. Now, when you do the sums, though, it doesn't really pan out. If you compare an individual who has slept at night, or stayed awake and hasn't moved very much, the energy saving of sleeping is about 110 calories a night. Now, that's the equivalent of a hot dog bun. Now, I would say that a hot dog bun is kind of a meager return for such a complicated and demanding behavior as sleep. So I'm less convinced by the energy conservation idea.
But the third idea I'm quite attracted to, which is brain processing and memory consolidation. What we know is that, if after you've tried to learn a task, and you sleep-deprive individuals, the ability to learn that task is smashed. It's really hugely attenuated. So sleep and memory consolidation is also very important. However, it's not just the laying down of memory and recalling it. What's turned out to be really exciting is that our ability to come up with novel solutions to complex problems is hugely enhanced by a night of sleep. In fact, it's been estimated to give us a threefold advantage. Sleeping at night enhances our creativity. And what seems to be going on is that, in the brain, those neural connections that are important, those synaptic connections that are important, are linked and strengthened, while those that are less important tend to fade away and be less important.
Okay. So we've had three explanations for why we might sleep, and I think the important thing to realize is that the details will vary, and it's probable we sleep for multiple different reasons. But sleep is not an indulgence. It's not some sort of thing that we can take on board rather casually. I think that sleep was once likened to an upgrade from economy to business class, you know, the equiavlent of. It's not even an upgrade from economy to first class. The critical thing to realize is that if you don't sleep, you don't fly. Essentially, you never get there, and what's extraordinary about much of our society these days is that we are desperately sleep-deprived.
So let's now look at sleep deprivation. Huge sectors of society are sleep-deprived, and let's look at our sleep-o-meter. So in the 1950s, good data suggests that most of us were getting around about eight hours of sleep a night. Nowadays, we sleep one and a half to two hours less every night, so we're in the six-and-a-half-hours-every-night league. For teenagers, it's worse, much worse. They need nine hours for full brain performance, and many of them, on a school night, are only getting five hours of sleep. It's simply not enough. If we think about other sectors of society, the aged, if you are aged, then your ability to sleep in a single block is somewhat disrupted, and many sleep, again, less than five hours a night. Shift work. Shift work is extraordinary, perhaps 20 percent of the working population, and the body clock does not shift to the demands of working at night. It's locked onto the same light-dark cycle as the rest of us. So when the poor old shift worker is going home to try and sleep during the day, desperately tired, the body clock is saying, "Wake up. This is the time to be awake." So the quality of sleep that you get as a night shift worker is usually very poor, again in that sort of five-hour region. And then, of course, tens of millions of people suffer from jet lag. So who here has jet lag? Well, my goodness gracious. Well, thank you very much indeed for not falling asleep, because that's what your brain is craving.
One of the things that the brain does is indulge in micro-sleeps, this involuntary falling asleep, and you have essentially no control over it. Now, micro-sleeps can be sort of somewhat embarrassing, but they can also be deadly. It's been estimated that 31 percent of drivers will fall asleep at the wheel at least once in their life, and in the , the statistics are pretty good: 100,000 accidents on the freeway have been associated with tiredness, loss of vigilance, and falling asleep. A hundred thousand a year. It's extraordinary. At another level of terror, we dip into the tragic accidents at Chernobyl and indeed the space shuttle Challenger, which was so tragically lost. And in the investigations that followed those disasters, poor judgment as a result of extended shift work and loss of vigilance and tiredness was attributed to a big chunk of those disasters.
So when you're tired, and you lack sleep, you have poor memory, you have poor creativity, you have increased impulsiveness, and you have overall poor judgment. But my friends, it's so much worse than that.
(Laughter)
If you are a tired brain, the brain is craving things to wake it up. So drugs, stimulants. Caffeine represents the stimulant of choice across much of the Western world. Much of the day is fueled by caffeine, and if you're a really naughty tired brain, nicotine. And of course, you're fueling the waking state with these stimulants, and then of course it gets to 11 o'clock at night, and the brain says to itself, "Ah, well actually, I need to be asleep fairly shortly. What do we do about that when I'm feeling completely wired?" Well, of course, you then resort to alcohol. Now alcohol, short-term, you know, once or twice, to use to mildly sedate you, can be very useful. It can actually ease the sleep transition. But what you must be so aware of is that alcohol doesn't provide sleep, a biological mimic for sleep. It sedates you. So it actually harms some of the neural proccessing that's going on during memory consolidation and memory recall. So it's a short-term acute measure, but for goodness sake, don't become addicted to alcohol as a way of getting to sleep every night.
Another connection between loss of sleep is weight gain. If you sleep around about five hours or less every night, then you have a 50 percent likelihood of being obese. What's the connection here? Well, sleep loss seems to give rise to the release of the hormone ghrelin, the hunger hormone. Ghrelin is released. It gets to the brain. The brain says, "I need carbohydrates," and what it does is seek out carbohydrates and particularly sugars. So there's a link between tiredness and the metabolic predisposition for weight gain.
Stress. Tired people are massively stressed. And one of the things of stress, of course, is loss of memory, which is what I sort of just then had a little lapse of. But stress is so much more. So if you're acutely stressed, not a great problem, but it's sustained stress associated with sleep loss that's the problem. So sustained stress leads to suppressed immunity, and so tired people tend to have higher rates of overall infection, and there's some very good studies showing that shift workers, for example, have higher rates of cancer. Increased levels of stress throw glucose into the circulation. Glucose becomes a dominant part of the vasculature and essentially you become glucose intolerant. Therefore, diabetes 2. Stress increases cardiovascular disease as a result of raising blood pressure. So there's a whole raft of things associated with sleep loss that are more than just a mildly impaired brain, which is where I think most people think that sleep loss resides.
So at this point in the talk, this is a nice time to think, well, do you think on the whole I'm getting enough sleep? So a quick show of hands. Who feels that they're getting enough sleep here? Oh. Well, that's pretty impressive. Good. We'll talk more about that later, about what are your tips.
So most of us, of course, ask the question, "Well, how do I know whether I'm getting enough sleep?" Well, it's not rocket science. If you need an alarm clock to get you out of bed in the morning, if you are taking a long time to get up, if you need lots of stimulants, if you're grumpy, if you're irritable, if you're told by your work colleagues that you're looking tired and irritable, chances are you are sleep-deprived. Listen to them. Listen to yourself.
What do you do? Well -- and this is slightly offensive -- sleep for dummies: Make your bedroom a haven for sleep. The first critical thing is make it as dark as you possibly can, and also make it slightly cool. Very important. Actually, reduce your amount of light exposure at least half an hour before you go to bed. Light increases levels of alertness and will delay sleep. What's the last thing that most of us do before we go to bed? We stand in a massively lit bathroom looking into the mirror cleaning our teeth. It's the worst thing we can possibly do before we went to sleep. Turn off those mobile phones. Turn off those computers. Turn off all of those things that are also going to excite the brain. Try not to drink caffeine too late in the day, ideally not after lunch. Now, we've set about reducing light exposure before you go to bed, but light exposure in the morning is very good at setting the biological clock to the light-dark cycle. So seek out morning light. Basically, listen to yourself. Wind down. Do those sorts of things that you know are going to ease you off into the honey-heavy dew of slumber.
Okay. That's some facts. What about some myths?
Teenagers are lazy. No. Poor things. They have a biological predisposition to go to bed late and get up late, so give them a break.
We need eight hours of sleep a night. That's an average. Some people need more. Some people need less. And what you need to do is listen to your body. Do you need that much or do you need more? Simple as that.
Old people need less sleep. Not true. The sleep demands of the aged do not go down. Essentially, sleep fragments and becomes less robust, but sleep requirements do not go down.
And the fourth myth is, early to bed, early to rise makes a man healthy, wealthy and wise. Well that's wrong at so many different levels. (Laughter) There is no, no evidence that getting up early and going to bed early gives you more wealth at all. There's no difference in socioeconomic status. In my experience, the only difference between morning people and evening people is that those people that get up in the morning early are just horribly smug.
(Laughter) (Applause)
Okay. So for the last part, the last few minutes, what I want to do is change gears and talk about some really new, breaking areas of neuroscience, which is the association between mental health, mental illness and sleep disruption. We've known for 130 years that in severe mental illness, there is always, always sleep disruption, but it's been largely ignored. In the 1970s, when people started to think about this again, they said, "Yes, well, of course you have sleep disruption in schizophrenia because they're on anti-psychotics. It's the anti-psychotics causing the sleep problems," ignoring the fact that for a hundred years previously, sleep disruption had been reported before anti-psychotics.
So what's going on? Lots of groups, several groups are studying conditions like depression, schizophrenia and bipolar, and what's going on in terms of sleep disruption. We have a big study which we published last year on schizophrenia, and the data were quite extraordinary. In those individuals with schizophrenia, much of the time, they were awake during the night phase and then they were asleep during the day. Other groups showed no 24-hour patterns whatsoever. Their sleep was absolutely smashed. And some had no ability to regulate their sleep by the light-dark cycle. They were getting up later and later and later and later each night. It was smashed.
So what's going on? And the really exciting news is that mental illness and sleep are not simply associated but they are physically linked within the brain. The neural networks that predispose you to normal sleep, give you normal sleep, and those that give you normal mental health are overlapping. And what's the evidence for that? Well, genes that have been shown to be very important in the generation of normal sleep, when mutated, when changed, also predispose individuals to mental health problems. And last year, we published a study which showed that a gene that's been linked to schizophrenia, which, when mutated, also smashes the sleep. So we have evidence of a genuine mechanistic overlap between these two important systems.
Other work flowed from these studies. The first was that sleep disruption actually precedes certain types of mental illness, and we've shown that in those young individuals who are at high risk of developing bipolar disorder, they already have a sleep abnormality prior to any clinical diagnosis of bipolar. The other bit of data was that sleep disruption may actually exacerbate, make worse the mental illness state. My colleague Dan Freeman has used a range of agents which have stabilized sleep and reduced levels of paranoia in those individuals by 50 percent.
So what have we got? We've got, in these connections, some really exciting things. In terms of the neuroscience, by understanding the neuroscience of these two systems, we're really beginning to understand how both sleep and mental illness are generated and regulated within the brain. The second area is that if we can use sleep and sleep disruption as an early warning signal, then we have the chance of going in. If we know that these individuals are vulnerable, early intervention then becomes possible. And the third, which I think is the most exciting, is that we can think of the sleep centers within the brain as a new therapeutic target. Stabilize sleep in those individuals who are vulnerable, we can certainly make them healthier, but also alleviate some of the appalling symptoms of mental illness.
So let me just finish. What I started by saying is take sleep seriously. Our attitudes toward sleep are so very different from a pre-industrial age, when we were almost wrapped in a duvet. We used to understand intuitively the importance of sleep. And this isn't some sort of crystal-waving nonsense. This is a pragmatic response to good health. If you have good sleep, it increases your concentration, attention, decision-making, creativity, social skills, health. If you get sleep, it reduces your mood changes, your stress, your levels of anger, your impulsivity, and your tendency to drink and take drugs. And we finished by saying that an understanding of the neuroscience of sleep is really informing the way we think about some of the causes of mental illness, and indeed is providing us new ways to treat these incredibly debilitating conditions.
Jim Butcher, the fantasy writer, said, "Sleep is God. Go worship." And I can only recommend that you do the same.
Thank you for your attention.
(Applause)