Brain Rules PDF Summary
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12 Principles for Surviving and Thriving at Work, Home, and School
Do you know how your brain works?
Let us burst your bubble: you don’t.
Which is why it’s more than necessary that you take some time to learn the 12 most essential
Who Should Read “Brain Rules”? And Why?
Even though this book is suited for neuroscientists and psychologists as well, it probably works best as one of the best popular science books on how the brain works for laypeople and students.
It would be great if people in power read it too – Medina’s ideas on how our classrooms and business environments should look like seem to us not only great but revolutionary.
If only some of them could become reality.
About John Medina
John J. Medina is a developmental molecular biologist and research consultant, working primarily on issues related to mental health with pharmaceutical and biotechnological companies.
The author of the “Molecules of the Mind” column in the Psychiatric Times journal, he is also the founding director of the Talaris Research Institute.
Brain Rules, part of a trilogy of similarly titled books (with Brain Rules for Aging Well and Brain Rules for Baby) is one of the many books on the subject he has so far authored, such as What You Need to Know About Alzheimer’s, The Clock of Ages and Depression.
Find out more at http://www.medinascientific.com/
“Brain Rules PDF Summary”
“I am a nice guy, but I am a grumpy scientist,” says John Medina in the “Introduction” to Brain Rules, a reader-friendly exploration of our brain powers with applicable revelations, based exclusively on peer-reviewed scientific studies.
That’s what the sentence above refers to, in fact: for a study to appear in his book, Medina goes on, “it has to pass what some at The Boeing Company (for which I have done some consulting) call MGF: the Medina Grump Factor.”
What does Medina Grump Factor mean?
“That means,” explains the guy after whom it is named, “the supporting research for each of my points must first be published in a peer-reviewed journal and then successfully replicated.”
In other words, all of the rules presented here are factual and verified; they are, as Medina calls them, “things we know about how the brain works.”
Unfortunately, it seems that most of these things are either willfully ignored by the people who have created – and carry on creating – our societies or are not known to anyone outside the neuroscientific community.
Because, in a nutshell, what they all point to is this:
If you wanted to create an education environment that was directly opposed to what the brain was good at doing, you probably would design something like a classroom. If you wanted to create a business environment that was directly opposed to what the brain was good at doing, you probably would design something like a cubicle. And if you wanted to change things, you might have to tear down both and start over.
Well, this is to book which can help you start off on the right foot.
Key Lessons from “Brain Rules”
1. Rule #1: Exercise Boosts Brain Power
2. Rule #2: The Human Brain Evolved, Too
3. Rule #3: Every Brain Is Wired Differently
4. Rule #4: We Don’t Pay Attention to Boring Things
5. Rule #5: Repeat to Remember
6. Rule #6: Remember to Repeat
7. Rule #7: Sleep Well, Think Well
8. Rule #8: Stressed Brains Don’t Learn the Same Way
9. Rule #9: Stimulate More of the Senses
10. Rule #10: Vision Trumps All Other Senses
11. Rule #11: Male and Female Brains Are Different
12. Rule #12: We Are Powerful and Natural Explorers
Rule #1: Exercise Boosts Brain Power
Let’s get straight to the point: your body is not built to sit 8 hours a day; your brain likes that even less.
Think of it this way: you’ve become who you are – aka homo sapiens – not because your predecessors say 8 hours a day, but because they walked at least 10 and as much as 20 kilometers a day.
Your brain still craves this experience!
All of the studies consistently prove this: exercise boosts brain power, especially in sedentary populations.
Whether it’s long-term memory (see Rule #6) or problem-solving tasks, attention (see Rule #4) or reasoning – exercisers always outperform couch potatoes.
And there’s a physiological reason for this!
Namely, exercising stimulates the production of certain hormones, one of which is the BDNF.
That acronym stands for brain-derived neurotrophic factor in the scientific community, but in layman’s terms, you can translate that to “boost dem neurons, friend.”
Because BDNF refreshes your neurons and strengthens the connections between them and that’s great both for your problem-solving capabilities and long-term memory.
To sum up in Medina’s words: “To improve your thinking skills, move… Aerobic exercise just twice a week halves your risk of dementia.”
Rule #2: The Human Brain Evolved, Too
Now, it’s important to note that when we use the word “brain,” it’s almost more appropriate to use it in the plural.
Because we don’t have one, but three brains inside our skulls.
The oldest one is the lizard brain, which is “lively as Las Vegas” and controls “most of your body’s housekeeping chores;” namely, “breathing, heart rate, sleeping, and waking.”
The second one is the (paleo)mammalian brain, which is responsible for your survival, or as some scientists say, the four F’s: “fighting, feeding, fleeing, and … reproductive behavior.”
Finally, the third one is the human brain, the one responsible for all the complex tasks, the pinnacle of evolution.
Now, everybody expects from you to have your human brain active at all times; the problem is the other two brains are still there; most of these rules concern the mammalian brain which is a large part of us and is still too powerful to be ignored.
Until we evolve to become something more than sapiens, we’re still part animals; and we need to react appropriately to this fact.
Rule #3: Every Brain Is Wired Differently
The brain may have evolved historically in humans as species, but it is also continually evolving (well, sort of) inside each and every one of us.
“What you do and learn in life,” writes Medina, “physically changes what your brain looks like – it literally rewires it.”
Think of your brain as an empty map containing no roads. More or less, all humans share the same blueprint (the same locations and places, the same milestones), but no two humans connect these by drawing upon the map the same, exact roads.
In other words: “no two people’s brains store the same information in the same way in the same place.”
It is wiring – connecting the different regions of the brain – which makes virtuous pianists and it is wiring which helps some people be so great at chess.
However, wiring is also the reason why some people score high at IQ tests, and others don’t.
“We have a great number of ways of being intelligent,” writes Medina, “many of which don’t show up on IQ tests.”
Rule #4: We Don’t Pay Attention to Boring Things
When it comes to paying attention, your brain is, simply put, not evolved enough to multitask.
So even though you try to talk on your cell phone while driving, the fact is that your brain is constantly switching on and off between the two; what actually happens inside your brain when you think you’re multitasking is chaotic singletasking between more than one assignment.
It is literally impossible to multitask: “the brain’s attentional ‘spotlight’ can focus on only one thing at a time.”
Also, as you know full well from every single PowerPoint presentation you’ve seen so far in your life, it is impossible for you to pay attention for more than 10 minutes at anything.
So if you want to keep your audience’s attention, do something which will arouse their emotions at 9 minutes and 59 seconds!
Rule #5: Repeat to Remember
The Romans had a nice saying: repetitio mater studiorum est; repetition is the mother of learning.
Because that’s precisely how your brain works when it tries to remember things; it first encodes them, and then stores them; however, unless you try to decode the info repeatedly, your brain just forgets the code, and, thus, you forget the information.
This is the reason why you sometimes can suddenly recall something you’ve forgotten after reproducing the environment or the immediate surrounding information of the one you’re interested in.
The more elaborate the initial encoding, the longer you’ll remember the info; the more often you visit the information stored, the more likely it will become part of your long-term memory.
Which brings us to Rule #6.
Rule #6: Remember to Repeat
“Most memories disappear within minutes,” says John Medina, “but those that survive the fragile period strengthen with time”:
Long-term memories are formed in a two-way conversation between the hippocampus and the cortex, until the hippocampus breaks the connection and the memory is fixed in the cortex – which can take years.
After this process is finalized, you don’t even need to think to remember something: your brain does it by default.
But what does this mean in practical terms?
Simply put, it means that the schools of the future should completely eliminate homework and instead focus on initiating “review holidays.”
In other words, if every third or fourth day, you repeat with your class your notes of the previous days (in summarized form), then you’ll have no need of homework.
Rule #7: Sleep Well, Think Well
Let us ask you a question: do you feel tired every day around 3 o’clock?
If so, do you know why?
No, it’s not because of your work or your kids or what not – it’s because your brain really needs a nap from time to time!
Put it this way: sleeping is not exactly something evolution should encourage; after all, it’s not a great idea to sleep for 8 hours when there are lions around you; and yet, sleeping has endured to this day.
It’s just too essential.
Afternoon naps especially!
Because, even though “people vary in how much sleep they need and when they prefer to get it, but the biological drive for an afternoon nap is universal.”
Don’t believe us?
According to one study, a 26-minute nap improved NASA pilots’ performance by 34 percent!
So, what are you waiting for?
It’s time for a sleep revolution!
Rule #8: Stressed Brains Don’t Learn the Same Way
As we have already told you, stress is the direct product of your body’s defense mechanism.
In a nutshell, when in a fight-or-flee situation, your body switches off all the systems which are not necessary for your immediate survival and turns on all those which are.
Your body’s defense system – the release of adrenaline and cortisol – is built for an immediate response to a serious but passing danger, such as a saber-toothed tiger. Chronic stress, such as hostility at home, dangerously deregulates a system built only to deal with short-term responses.
So, in other words, when the danger of a saber-toothed tiger attack passed, the bodies of the Neanderthals went back to normal; however, ours don’t – because saber-toothed tigers have evolved into never-ending streams of abstract fears, be they deadlines or homework assignments.
Unfortunately, chronic stress causes your brain to stop working properly, “crippling your ability to learn and remember.”
Want better schools and offices?
Make them as stress-free as possible!
Rule #9: Stimulate More of the Senses
You know why some people have unlimited memories?
Because they include more of their senses to remember things.
Just ask synesthetes, aka people who smell colors or see sounds; apparently, they also remember things unusually well.
But there’s a very understandable reason for this.
“We absorb information about an event through our senses,” reminds us John Medina, “translate it into electrical signals (some for sight, others from sound, etc.), disperse those signals to separate parts of the brain, then reconstruct what happened, eventually perceiving the event as a whole.”
Memory, as we learned above (Rules #3, #5 and #6) is all about your capability to connect the dots, aka wire the parts of the brain which keep the information.
Just imagine the power when you are hardwired to connect them because you experience everything in more than one sense!
Why not use this while learning new things?
Also, an interesting trivia: because smell signals bypass the thalamus, smells bring back memories most forcefully.
Rule #10: Vision Trumps All Other Senses
Leonardo da Vinci knew this intuitively; science has all but proven it: “vision is by far our most dominant sense, taking up half of our brain’s resources.”
In fact, it’s wrong to say that we see with our eyes; we’re, in truth, seeing with our brains. Consequently, “what we see is only what our brain tells us we see.”
It’s only natural that this is not 100 percent accurate; in fact, this explains, in no uncertain terms, why some people see ghosts or visions. Simply put, their eyes are seeing what their brain tells them to see, even though there’s nothing of that sort in reality.
Vision is so important, in fact, that, as Wittgenstein argued, it’s possible that you can’t really understand things unless you translate them into images.
That’s the reason why you use analogies and why the only way you can comprehend the beginning of Beethoven’s Fifth is by saying that it’s Destiny knocking on the door.
“We learn and remember best through pictures,” concludes Medina, “not through written or spoken words.”
Rule #11: Male and Female Brains Are Different
No matter what religions say, women are actually the more complex sex: the X chromosome (which females have two of, and men only one of) carries “an unusually large percentage of genes involved in brain manufacture.”
Also, the X chromosome carries about 1,500 genes, fifteen times more than the number of genes in the corresponding male Y chromosome.
In other words, the brains of males and females are different both structurally and biochemically; even though this explains how men and women react to stress and why men are generally the more stable sex, we don’t know if the differences go past, say, the speed of serotonin production.
Also, we don’t know whether we should encourage these differences or balance them out; and, if the latter one, in which direction.
So, anyone who says that he knows and he’s advocating either of the views, he’s lying – because science hasn’t said the final word on this just yet.
Rule #12: We Are Powerful and Natural Explorers
If you observe a baby for a while, you’ll immediately understand that we’ve evolved to learn new things “not by passive reaction to the environment but by active testing through observation, hypothesis, experiment, and conclusion.”
In other words, you posit a hypothesis (“lions are great creatures”), then look for errors in it (“wow: that look is slightly menacing”), and then, another part of your brain tells you that you need to change your behavior if you want to survive on this planet (“you better run”).
The great news?
“Some parts of our adult brains stay as malleable as a baby’s,” says Medina.
Yes, that means exactly what you think it means: you can create neurons and learn new things throughout your whole life.
Since you’re reading this summary, you’re actually doing that right now.
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“Brain Rules Quotes”The most common communication mistakes? Relating too much information, with not enough time devoted to connecting the dots. Click To Tweet We must do a better job of encouraging lifelong curiosity. Click To Tweet One of the greatest predictors of successful aging, they found, is the presence or absence of a sedentary lifestyle. Click To Tweet Studies show that a person who is interrupted takes 50 percent longer to accomplish a task. Not only that, he or she makes up to 50 percent more errors. Click To Tweet Emotionally charged events are better remembered—for longer, and with more accuracy – than neutral events. Click To Tweet
Our Critical Review
Brain Rules seems like one of the best candidates for the Brain 101 book you’ve always wanted to find, but never could.
It’s science-based, nicely structured, simply written, and offers many practically applicable ideas.And there’s a whole website – which includes references and a film – if you want to delve into the subject further once you finish the book.
Learn more and more, in the speed that the world demands.