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9 myths about psychology: debunked

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    You've heard of your I.Q.,
    your general intelligence,
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    but what's your Psy-Q?
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    How much do you know
    about what makes you tick,
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    and how good are you
    at predicting other people's behavior
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    or even your own?
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    And how much of what you think you know
    about psychology is wrong?
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    Let's find out by counting down
    the top 10 myths of psychology.
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    You've probably heard it said
    that when it comes to their psychology,
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    it's almost as if men are from Mars
    and women are from Venus.
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    But how different
    are men and women really?
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    To find out, let's start
    by looking at something
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    on which men and women really do differ
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    and plotting some psychological
    gender differences on the same scale.
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    One thing men and women
    do really differ on
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    is how far they can throw a ball.
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    So if we look at the data for men here,
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    we see what is called
    a normal distribution curve.
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    A few men can throw a ball really far,
    and a few men not far at all,
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    but most a kind of average distance.
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    And women share
    the same distribution as well,
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    but actually there's
    quite a big difference.
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    In fact, the average man
    can throw a ball further
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    than about 98 percent of all women.
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    So now let's look at what
    some psychological gender differences
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    look like on the same standardized scale.
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    Any psychologist will tell you
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    that men are better
    at spatial awareness than women --
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    so things like map-reading,
    for example -- and it's true,
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    but let's have a look
    at the size of this difference.
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    It's tiny; the lines are so close
    together they almost overlap.
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    In fact, the average woman is better
    than 33 percent of all men,
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    and of course, if that was 50 percent,
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    then the two genders
    would be exactly equal.
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    It's worth bearing in mind that this
    difference and the next one I'll show you
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    are pretty much the biggest
    psychological gender differences
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    ever discovered in psychology.
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    So here's the next one.
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    Any psychologist will tell you
    that women are better
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    with language and grammar than men.
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    So here's performance
    on the standardized grammar test.
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    There go the women. There go the men.
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    Again, yes, women are better on average,
    but the lines are so close
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    that 33 percent of men
    are better than the average woman,
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    and again, if it was 50 percent,
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    that would represent
    complete gender equality.
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    So it's not really
    a case of Mars and Venus.
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    It's more a case of, if anything,
    Mars and Snickers:
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    basically the same, but one's maybe
    slightly nuttier than the other.
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    I won't say which.
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    Now we've got you warmed up.
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    Let's psychoanalyze you using
    the famous Rorschach inkblot test.
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    So you can probably see two, I dunno,
    two bears or two people or something.
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    But what do you think they're doing?
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    Put your hand up if you think
    they're saying hello.
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    Not many people. Okay.
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    Put your hands up if you think
    they are high-fiving.
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    Okay. What if you think they're fighting?
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    Only a few people there.
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    Okay, so if you think they're
    saying hello or high-fiving,
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    then that means you're a friendly person.
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    If you think they're fighting,
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    you're a bit more of a
    nasty, aggressive person.
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    Are you a lover or a fighter, basically.
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    What about this one?
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    This isn't really a voting one, so on
    three everyone shout out what you see.
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    One, two, three.
    (Audience shouting)
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    I heard hamster. Who said hamster?
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    That was very worrying.
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    A guy there said hamster.
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    Well, you should see
    some kind of two-legged animal here,
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    and then the mirror image of them there.
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    If you didn't, then this means
    that you have difficulty
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    processing complex situations
    where there's a lot going on.
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    Except, of course,
    it doesn't mean that at all.
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    Rorschach inkblot tests
    have basically no validity
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    when it comes to diagnosing
    people's personality
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    and are not used
    by modern-day psychologists.
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    In fact, one recent study found
    that when you do try
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    to diagnose people's personalities
    using Rorschach inkblot tests,
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    schizophrenia was diagnosed
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    in about one sixth of apparently
    perfectly normal participants.
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    So if you didn't do that well on this,
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    maybe you are not
    a very visual type of person.
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    So let's do another
    quick quiz to find out.
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    When making a cake, do you prefer to --
    so hands up for each one again --
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    do you prefer to use
    a recipe book with pictures?
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    Yeah, a few people.
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    Have a friend talk you through?
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    Or have a go, making it up
    as you go along?
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    Quite a few people there.
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    Okay, so if you said A,
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    then this means that you
    are a visual learner
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    and you learn best when information
    is presented in a visual style.
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    If you said B, it means
    you're an auditory learner,
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    that you learn best when information
    is presented to you in an auditory format.
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    And if you said C, it means
    that you're a kinesthetic learner,
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    that you learn best when you get stuck in
    and do things with your hands.
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    Except, of course,
    as you've probably guessed,
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    that it doesn't, because
    the whole thing is a complete myth.
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    Learning styles are made up and are
    not supported by scientific evidence.
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    So we know this because in
    tightly controlled experimental studies,
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    when learners are given material to learn
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    either in their preferred style
    or an opposite style,
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    it makes no difference at all to the
    amount of information that they retain.
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    And if you think about it
    for just a second,
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    it's just obvious
    that this has to be true.
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    It's obvious that
    the best presentation format
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    depends not on you,
    but on what you're trying to learn.
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    Could you learn to drive a car,
    for example,
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    just by listening to someone
    telling you what to do
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    with no kinesthetic experience?
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    Could you solve simultaneous equations
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    by talking them through in your head
    and without writing them down?
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    Could you revise
    for your architecture exams
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    using interpretive dance
    if you're a kinesthetic learner?
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    No. What you need to do
    is match the material to be learned
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    to the presentation format, not you.
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    I know many of you are A-level students
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    that will have recently gotten
    your GCSE results.
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    And if you didn't quite get
    what you were hoping for,
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    then you can't really blame
    your learning style,
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    but one thing that you might want
    to think about blaming is your genes.
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    So what this is all about is a
    recent study at University College London
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    found that 58 percent of the variation
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    between different students
    and their GCSE results
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    was down to genetic factors.
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    That sounds like a very precise figure,
    so how can we tell?
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    Well, when we want to unpack
    the relative contributions
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    of genes and the environment,
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    what we can do is do a twin study.
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    So identical twins share
    100 percent of their environment
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    and 100 percent of their genes,
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    whereas non-identical twins
    share 100 percent of their environment,
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    but just like any brother and sister,
    share only 50 percent of their genes.
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    So by comparing how similar
    GCSE results are in identical twins
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    versus non-identical twins,
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    and doing some clever math,
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    we can an idea of how much variation
    and performance is due to the environment
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    and how much is due to genes.
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    And it turns out that it's
    about 58 percent due to genes.
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    So this isn't to undermine the hard work
    that you and your teachers here put in.
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    If you didn't quite get the GCSE results
    that you were hoping for,
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    then you can always try blaming
    your parents, or at least their genes.
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    One thing that you shouldn't blame
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    is being a left-brained
    or right-brained learner,
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    because again, this is a myth.
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    So the myth here is that
    the left brain is logical,
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    it's good with equations like this,
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    and the right brain is more creative,
    so the right brain is better at music.
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    But again, this is a myth
    because nearly everything that you do
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    involves nearly all parts
    of your brain talking together,
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    even just the most mundane thing
    like having a normal conversation.
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    However, perhaps one reason
    why this myth has survived
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    is that there is
    a slight grain of truth to it.
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    So a related version of the myth
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    is that left-handed people are
    more creative than right-handed people,
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    which kind of makes sense because
    your brain controls the opposite hands,
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    so left-handed people,
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    the right side of the brain
    is slightly more active
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    than the left-hand side of the brain,
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    and the idea is the right-hand side
    is more creative.
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    Now, it isn't true per se
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    that left-handed people are more creative
    than right-handed people.
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    What is true that ambidextrous people,
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    or people who use both hands
    for different tasks,
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    are more creative thinkers
    than one-handed people,
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    because being ambidextrous involves
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    having both sides of the brain
    talk to each other a lot,
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    which seems to be involved
    in creating flexible thinking.
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    The myth of the creative left-hander
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    arises from the fact
    that being ambidextrous
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    is more common amongst
    left-handers than right-handers,
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    so a grain of truth in the idea
    of the creative left-hander,
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    but not much.
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    A related myth that you've
    probably heard of
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    is that we only use
    10 percent of our brains.
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    This is, again, a complete myth.
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    Nearly everything that we do,
    even the most mundane thing,
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    uses nearly all of our brains.
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    That said, it is of course true
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    that most of us don't use our brainpower
    quite as well as we could.
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    So what could we do
    to boost our brainpower?
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    Maybe we could listen
    to a nice bit of Mozart.
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    Have you heard of the idea
    of the Mozart effect?
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    So the idea is that listening
    to Mozart makes you smarter
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    and improves your
    performance on I.Q. tests.
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    Now again, what's interesting
    about this myth
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    is that although it's basically a myth,
    there is a grain of truth to it.
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    So the original study found that
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    participants who were played
    Mozart music for a few minutes
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    did better on a subsequent I.Q. test
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    than participants who simply
    sat in silence.
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    But a follow-up study recruited
    some people who liked Mozart music
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    and then another group of people
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    who were fans of
    the horror stories of Stephen King.
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    And they played the people
    the music or the stories.
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    The people who preferred
    Mozart music to the stories
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    got a bigger I.Q. boost
    from the Mozart than the stories,
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    but the people who preferred
    the stories to the Mozart music
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    got a bigger I.Q. boost
    from listening to the Stephen King stories
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    than the Mozart music.
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    So the truth is that listening
    to something that you enjoy
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    perks you up a bit
    and gives you a temporary I.Q. boost
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    on a narrow range of tasks.
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    There's no suggestion that
    listening to Mozart,
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    or indeed Stephen King stories,
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    is going to make you any smarter
    in the long run.
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    Another version of the Mozart myth
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    is that listening to Mozart can make you
    not only cleverer but healthier, too.
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    Unfortunately, this doesn't
    seem to be true
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    of someone who listened
    to the music of Mozart almost every day,
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    Mozart himself,
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    who suffered from gonorrhea,
    smallpox, arthritis,
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    and, what most people think eventually
    killed him in the end, syphilis.
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    This suggests that Mozart
    should have bit more careful, perhaps,
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    when choosing his sexual partners.
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    But how do we choose a partner?
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    So a myth that I have to say
    is sometimes spread a bit by sociologists
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    is that our preferences in a romantic
    partner are a product of our culture,
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    that they're very culturally specific.
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    But in fact, the data don't back this up.
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    A famous study surveyed people from
    [37] different cultures across the globe,
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    from Americans to Zulus,
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    on what they look for in a partner.
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    And in every single culture
    across the globe,
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    men placed more value
    on physical attractiveness in a partner
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    than did women,
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    and in every single culture, too,
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    women placed more importance than did men
    on ambition and high earning power.
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    In every culture, too,
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    men preferred women
    who were younger than themselves,
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    an average of, I think it was 2.66 years,
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    and in every culture, too,
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    women preferred men
    who were older than them,
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    so an average of 3.42 years,
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    which is why we've got here
    "Everybody needs a Sugar Daddy."
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    So moving on from trying
    to score with a partner
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    to trying to score in basketball
    or football or whatever your sport is.
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    The myth here is that sportsmen go through
    hot-hand streaks, Americans call them,
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    or purple patches,
    we sometimes say in England,
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    where they just can't miss,
    like this guy here.
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    But in fact, what happens is that
    if you analyze the pattern
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    of hits and misses statistically,
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    it turns out that it's
    nearly always at random.
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    Your brain creates patterns
    from the randomness.
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    If you toss a coin,
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    a streak of heads or tails is going
    to come out somewhere in the randomness,
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    and because the brain likes to see
    patterns where there are none,
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    we look at these streaks
    and attribute meanings to them
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    and say, "Yeah he's really on form today,"
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    whereas actually you would
    get the same pattern
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    if you were just getting
    hits and misses at random.
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    So an exception to this, however,
    is penalty shootouts.
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    A recent study looking
    at penalty shootouts in football
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    shows that players who represent countries
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    with a very bad record
    in penalty shootouts,
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    like, for example, England,
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    tend to be quicker to take their shots
    than countries with a better record,
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    and presumably as a result,
    they're more likely to miss.
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    Which raises the question
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    of if there's any way that we
    could improve people's performance.
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    And one thing you might think about doing
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    is punishing people for their misses
    and seeing if that improves them.
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    This idea, the effect that punishment
    can improve performance,
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    is what participants
    thought they were testing
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    in Milgram's famous learning
    and punishment experiment
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    that you've probably heard about
    if you're a psychology student.
  • 11:54 - 11:57
    The story goes that participants
    were prepared to give
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    what they believed to be fatal
    electric shocks to a fellow participant
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    when they got a question wrong,
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    just because someone
    in a white coat told them to.
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    But this story is a myth
    for three reasons.
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    Firstly and most crucially, the lab coat
    wasn't white, it was in fact grey.
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    Secondly, the participants
    were told before the study
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    and reminded any time
    they raised a concern,
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    that although the shocks were painful,
    they were not fatal
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    and indeed caused
    no permanent damage whatsoever.
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    And thirdly, participants
    didn't give the shocks
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    just because someone
    in the coat told them to.
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    When they were interviewed
    after the study,
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    all the participants said
    that they firmly believed
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    that the learning and punishment study
    served a worthy scientific purpose
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    which would have
    enduring gains for science
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    as opposed to the momentary nonfatal
    discomfort caused to the participants.
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    Okay, so I've been talking
    for about 12 minutes now,
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    and you've probably been
    sitting there listening to me,
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    analyzing my speech patterns
    and body language
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    and trying to work out if you should
    take any notice of what I'm saying,
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    whether I'm telling the truth
    or whether I'm lying,
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    but if so you've
    probably completely failed,
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    because although we all think
    we can catch a liar
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    from their body language
    and speech patterns,
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    hundreds of psychological tests
    over the years have shown
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    that all of us, including
    police officers and detectives,
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    are basically at chance when it comes
    to detecting lies from body language
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    and verbal patterns.
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    Interestingly, there is one exception:
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    TV appeals for missing relatives.
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    It's quite easy to predict
    when the relatives are missing
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    and when the appealers have in fact
    murdered the relatives themselves.
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    So hoax appealers are more likely
    to shake their heads, to look away,
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    and to make errors in their speech,
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    whereas genuine appealers are more likely
  • 13:35 - 13:38
    to express hope that the person
    will return safely
  • 13:38 - 13:40
    and to avoid brutal language.
  • 13:40 - 13:44
    So, for example, they might say
    "taken from us" rather than "killed."
  • 13:44 - 13:47
    Speaking of which,
    it's about time I killed this talk,
  • 13:47 - 13:50
    but before I do, I just want
    to give you in 30 seconds
  • 13:50 - 13:53
    the overarching myth of psychology.
  • 13:53 - 13:58
    So the myth is that psychology is just
    a collection of interesting theories,
  • 13:58 - 14:01
    all of which say something useful
    and all of which have something to offer.
  • 14:01 - 14:04
    What I hope to have shown you
    in the past few minutes
  • 14:04 - 14:05
    is that this isn't true.
  • 14:05 - 14:09
    What we need to do is assess
    psychological theories
  • 14:09 - 14:10
    by seeing what predictions they make,
  • 14:10 - 14:13
    whether that is that listening to Mozart
    makes you smarter,
  • 14:13 - 14:18
    that you learn better when information is
    presented in your preferred learning style
  • 14:18 - 14:22
    or whatever it is, all of these
    are testable empirical predictions,
  • 14:22 - 14:23
    and the only way we can make progress
  • 14:23 - 14:25
    is to test these predictions
    against the data
  • 14:25 - 14:28
    in tightly controlled
    experimental studies.
  • 14:28 - 14:31
    And it's only by doing so
    that we can hope to discover
  • 14:31 - 14:34
    which of these theories
    are well supported,
  • 14:34 - 14:37
    and which, like all the ones
    I've told you about today, are myths.
  • 14:37 - 14:38
    Thank you.
  • 14:38 - 14:42
    (Applause)
Title:
9 myths about psychology: debunked
Speaker:
Ben Ambridge
Description:

How much of what you think about your brain is actually wrong? In this whistlestop tour of dis-proved science, Ben Ambridge walks through 10 popular ideas about psychology that have been proven wrong — and uncovers a few surprising truths about how our brains really work.

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Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
14:55

English subtitles

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