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Why You Can't Remember Being a Baby - Video học tiếng Anh
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Why You Can't Remember Being a Baby
Why You Can't Remember Being a Baby
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0:00
Look at a photo of yourself as a one-year-old. You probably think
0:03
you're looking at a younger version of you, and that you've simply forgotten those early years.
0:08
But biologically… that’s not true.
0:10
Your brain didn't just misplace those memories. It actively formatted the hard
0:14
drive. The baby in that picture? It isn't you. It’s a completely different entity whose mind
0:19
was physically disassembled and overwritten so that your current consciousness could exist.
0:25
This is why you can’t remember being a baby.
0:28
Chapter One - The Stranger in the Album
0:30
You’ve probably heard the myth that the human body physically replaces itself every seven
0:35
years. But like a lot of the internet’s favorite and oft-repeated pop science,
0:39
it’s only half the real truth. While cells like your skin and gut cells - incidentally,
0:44
the ones most exposed to harsh sunlight and powerful acid - will replenish every few
0:48
weeks. So, you’ll keep plenty of your baby cells until you drop dead. For example, only about 40%
0:54
of the cells in your heart will cycle throughout your life, the rest are here for the long haul.
0:59
But your memories?
1:00
They aren’t nearly as durable.
1:02
You can’t remember being the baby in a photo, but the scary thing is seeing that photo will
1:07
make you think you remember it. In a process that scientists call Infantile or childhood amnesia,
1:13
a series of complex - but not mysterious - processes wipe that mental state clean. In
1:18
their place is a big, murky void that’s vulnerable to modern day information impressing upon it.
1:24
The fact is, the baby you in the album is completely alien to the modern day you. So alien,
1:30
that someone could show you a photo of a different baby and you’d start to believe that it was you.
1:35
Little by little, the old memories are shoved into the paper shredder and replaced by a new one.
1:41
When does it stop being the old you?
1:43
It’s such a disturbing question that philosophers
1:46
have two different models for this: The Ship of Theseus and The Sorites Paradox.
1:51
In the first, if, over a number of decades, you slowly replace each part of a ship in
1:56
repairs until none of the original parts remain, you’re left to wonder:
2:00
Is it the same ship? In the second, you need to consider a pile of sand:
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How many grains of sand do you have to remove before it stops being a pile? Or in our case,
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how many memories inside that baby brain need to fade before the baby fades, too?
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Are you real? Have you always been you? Or, scientifically,
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were you the second tenant waiting in the wings during infant brain development, ready to move in?
2:24
Chapter Two - The Hardware Illusion
2:27
The first thing you need to understand is that it’s not because babies are working
2:31
with weak hardware. In fact, the exact opposite is true.
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A baby’s brain is actually a high-performance Ferrari compared
2:38
to the busted down Honda Civic of a brain most of us are working with by middle-age.
2:42
As an adult, your brain makes up only 2% of your overall body mass. Before you’re born,
2:47
it’s over 10 times that, 25% just before birth. And even after birth, the brain still accounts for
2:53
an impressive 10% of the baby’s body mass. And for the first 3 months of your life,
2:58
your brain will continue to grow by 1% per day in a period of incomparably rapid brain
3:04
development. The infant brain is a powerful data sponge, with an astonishing 50% more synaptic
3:10
connections than an adult brain. If you had the kind of brain that you had as a baby as an adult,
3:17
imagine how quickly you could pick up new skills, learn new languages, and develop your personality.
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The neuroplasticity is unparalleled.
3:24
More than a million neural connections are created every second in the infant brain,
3:29
and this process exacts an insane metabolic cost. 60% of a baby’s energy goes directly to the
3:35
development of their brain. Even at 3 years old, your brain will be twice as active as the brain
3:39
of an adult. When you look at it through this lens, the average baby or toddler is a crawling,
3:45
babbling supercomputer before they can even recite their ABCs. Clearly, you don’t lose
3:50
all your baby memories just because your baby brain is an inherently weak piece of hardware.
3:55
But the wholesale deletion of your infant self isn’t a bug in the system, it’s a feature.
4:00
The infant brain has no problem encoding short term memories. But when it comes to long term
4:05
memories, there’s a structural bottleneck built into a vital part of your brain:
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The Hippocampus. It’s a small part of your limbic system that organizes your memories
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by picking which short term memories to encode deeply as long term memories. As
4:19
the authoritative study on the matter puts it, “during infancy, when hippocampal neurogenesis
4:24
levels are high and freshly generated memories tend to be rapidly forgotten.”
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Basically, out with the old, and in with the new.
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And when that old is out, it’s out forever. But that’s not the only process that seems
4:35
deadset on annihilating your childhood self. It turns out,
4:38
the very growth of your brain might just be the ultimate nail in the coffin…
4:43
Chapter Three - The Hard Drive Format
4:45
The 2014 research of Paul W Frankland and Sheena A Josselyn into the nature
4:50
of neurogenesis - that’s the creation of new neural tissue - has completely altered our view
4:54
on how the brain assassinates itself in order to be reborn. They call it a “Clearance Mechanism”.
5:00
It’s a way to prevent the brain from clogging itself up with junk data, like passwords for
5:05
accounts you no longer use, old lottery numbers, and what you had for breakfast 3 years ago to the
5:10
day. Keeping all that stuff in your brain would likely feel more like a curse than a superpower.
5:15
The particular Clearance Mechanism that Frankland and Josselyn identified has everything to do with
5:20
how new cells are generated in the subgranular zone of the dentate gyrus. That’s where they
5:26
first multiply before later joining up to the circuitry of the hippocampus. This is what
5:30
happens when you’re having new experiences and, in the process, creating new memories.
5:35
Imagine you had a box full of plastic balls, kind of like the ones you’d find in a ballpit.
5:40
Then we give you a new ball, and tell you that we want you to move it to the bottom
5:44
of the box… Without moving any of the other balls in the process. Impossible, right?
5:49
That’s exactly how the new cells created in the subgranular zone
5:52
of the dentate gyrus interfere with the structure of the hippocampus.
5:56
You can’t add something new to a closed system without
5:59
fundamentally altering what’s already in there. To quote the study’s results,
6:03
“as new cells integrate into the hippocampus they necessarily remodel existing circuitry.
6:08
This remodeling may degrade memories already stored in those circuits.”
6:12
It’s not just adding to the circuits, it’s scrambling them.
6:16
The more you learn, the less you know.
6:18
The process of growing up, when viewed in light of these findings, is almost like upgrading
6:23
a system’s RAM while the computer is still running. It’s a violent incursion that upsets
6:27
the established order and rips through the mental architecture that’s already there. This research
6:32
is an insane paradigm shift for a huge number of reasons, like analyzing the way that established
6:37
and new memories interact. It also shows that by targeting specific parts of the brain, we may find
6:43
new avenues of treatment for memory-eroding disorders like amnesia and dementia.
6:47
It also continues carrying a disturbing pattern: The “You” that exists as a baby seems
6:53
utterly doomed by fate due to processes inherent in your body and brain as you grow up. And the
6:59
insane thing is, we’re still only scratching the surface of just how many natural processes
7:03
in the body seem to be pitching in on this conspiracy against your own mind.
7:08
Chapter Four - The Synaptic Massacre
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The human brain is like real estate: Space is always a factor.
7:15
The size of your skull will always limit the physical size of your brain.
7:18
The physical size of your brain will in turn always limit the number of synaptic
7:22
connections possible within it. Like I said earlier, when you're an infant,
7:26
your brain is an absolute sponge for all of life’s data around you. In that time you’ll pick up a
7:32
lot of valuable information, from language to knowing you shouldn’t touch a hot stove.
7:36
Inevitably, like someone who clicks the download link on every file they see on the internet,
7:41
your brain is also going to vacuum up a lot of junk, which can range from useless
7:46
to actively dangerous. That is why, when a person begins to hit puberty,
7:50
their mind and memories undergo a violent period of culling known as “Synaptic Pruning”, which,
7:55
in practice, means an insane massacre of countless memories. And if you’re
7:59
watching this and aged between 12 and 30, it’s happening to you right now. You’re right there
8:05
in the liminal space between the death of who you were and the becoming of who you’ll be.
8:09
And what synapses will be pruned depends entirely on each individual person, too. Think of it as the
8:15
principle of “use it or lose it”, where the synaptic connections that you use most over
8:20
this period - the memories of people and places you see most often, the skills you use most and
8:25
so on. - will strengthen. The connections that are underused wither away and die.
8:30
You’ll receive plenty of benefits from the synaptic pruning process,
8:33
from increased focus to clearer memory to better sensory processing. But for
8:37
the “previous tenant” of your body, this is basically the fulfilment of armageddon.
8:42
You hit your absolute peak level of synapses at around age 3, and between then and 10 years old,
8:48
you’ll see an absolutely insane 50% of your extra synapses completely wiped out.
8:54
It’s like a city wiping out half its roads and bridges to reduce congestion on the others. The
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fascinating but tragic part of all this is that you’ll never actually truly know what you lost.
9:05
But even if you could get over the neurological hurdle to understand all this,
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there’s another locked door behind this one, and this is purely a psychological one…
9:15
Chapter Five - The Mirror and the Ghost
9:17
When do you actually start thinking of yourself as You?
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It sounds like the kind of question that people at a party would start asking each
9:24
other at around 2 AM, after a few too many. But it’s actually a question that
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psychologists have pondered in depth for decades. They’ve even devised a brilliant
9:33
test to investigate: The MSR, or “Mirror Self-Recognition”, test.
9:37
In 1970, psychologist Gordon Gallup Jr. had a bright idea that a human or any other animal’s
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degree of self-awareness could be measured by their ability to recognize their reflection
9:47
as themself, and not as another animal. The specific variant for human babies is mostly
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known as “The Rouge Test”, where rouge makeup is used to draw a dot somewhere on the child’s skin
9:58
that they couldn’t see. Usually in places like their forehead. If the baby saw the red dot in
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their reflection and immediately reached for their own forehead rather than for the mirror itself,
10:09
it was a reasonably strong sign that they had a degree of self-conception.
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But here’s the interesting part.
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In the first 12 months of their life, for the most part, babies almost uniformly fail the
10:19
mirror test. They do not see the strange little bald drooling creature in the mirror and think,
10:25
“That’s me”, because their sense of “Me” has not, in any real way, solidified. They instead,
10:30
in the earliest iterations of human studies, saw their reflection in the mirror as a “social
10:35
playmate.” It’s only between 20 and 24 months that recognition rose above 65%,
10:41
so before that, almost half of infants were simply seeing strangers in the mirror.
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How can you store memories of the self without even knowing what the self really
10:50
is? It leaves babies with the need to find a different way to contextualise memory,
10:55
but our main way of doing that doesn’t exactly become pre-coded, either.
10:59
Chapter Six - The Language Lock
11:02
One of the many items in the human toolkit that have given us dominance over planet
11:06
Earth is our ability to communicate with verbal and written language. Our vocabulary,
11:10
in many ways, is our way of drawing the borders of our imagination.
11:14
So, what does this mean for the brain before we develop language?
11:18
If feeling and sensation are the gooey organs of memory, then language is the skeleton that holds
11:23
it all together. Before language, this so-called “pre-verbal” or “somatic” memory is encoded in
11:29
pure sensation. But as children gain language skills in their first 2 to 3 years of age,
11:34
their way of encoding memory radically changes to use language as a kind of mental storage medium.
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And when the medium changes, the message is lost. A 2002 study by Gabrielle Simcock and
11:45
Harlene Hayne tried to discover whether children acquiring new vocabulary gave them the power
11:50
to describe pre-verbal memories. The results of their test still feel incredibly shocking today:
11:56
“By the time of the test, children of all ages had acquired most of the vocabulary necessary
12:01
to describe the target event. Despite this, they did not translate preverbal aspects of
12:06
their memory into language during the test. In no instance did a child verbally report information
12:11
about the event that was not part of his or her productive vocabulary at the time of encoding.
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We conclude that language development plays a pivotal role in childhood amnesia.”
12:22
In other words, as soon as you’re able to say, “Bye bye, baby”, that’s exactly what you should
12:27
be saying to all your memories before that time. But whenever you learn strange and
12:31
distressing information like this, you might find yourself looking for exceptions. Like,
12:36
what happens to the memories of people who can remember pretty much everything?
12:40
Chapter Seven - The HSAM Paradox
12:43
Sometimes, memory can be a curse.
12:45
Picture the most embarrassing moment of your life. Imagine being able to recall
12:50
that moment with absolute vivid clarity for the rest of your life. Such is the struggle of
12:55
people with Highly Superior Autobiographical Memory, or HSAM. This means that a person
13:01
with this condition can flawlessly remember everything that happened to them specifically.
13:06
This condition is exceedingly rare, with only around 60 people ever being
13:09
successfully diagnosed. Research is still ongoing, but currently the best guess as
13:14
to why it affects people is a larger temporal lobe, for memory processing,
13:18
and a bigger caudate nucleus, which plays a role in learning. And the existence of a condition like
13:24
this raises a fascinating question: Even among people who supposedly have perfect
13:28
recall, why can so many of them still not remember their earliest years as a baby?
13:33
For the most part, these hyper-realistic memories begin in late childhood. This
13:37
means that even when you have hyper memory ability, you still can’t escape the infant
13:43
memory guillotine that is childhood amnesia. It’s simply a natural and inevitable part of life.
13:49
But it feels impossible to accept this as an absolute without asking another question:
13:54
What’s the evolutionary benefit of throwing our earliest years in the garbage?
13:58
Chapter Eight - The Stability-Plasticity Dilemma
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It’s clear the brain as an organ is always changing, evolving,
14:05
adapting to the era of life it’s serving. And as your life progresses, simply put,
14:10
you need a different type of brain. In your earliest years, nothing is more important
14:13
than neuroplasticity. Your mind is like a soft, wet ball of clay, and every day,
14:18
the information it takes in begins to shape it. As you grow up, you get a better sense of
14:23
your path in life, and your experiences mold that clay into something specific. Let’s say,
14:28
for the sake of argument, that the ball of clay that is your brain gets molded into a cup.
14:34
But even in the shape of a cup, you shouldn’t pour hot coffee into wet clay. So,
14:38
what do you do? You put that cup into a kiln and bake it into its shape. In this moment,
14:43
the cup loses plasticity - the ability to be anything - and instead gains stability.
14:49
It’s just one thing now, but it’s a lot better at being that one thing than it was before.
14:54
Much the same process happens to your brain.
14:57
It loses the chance to exist in the world of potential, but in exchange,
15:01
it gets to be something, which is valuable in a global community of social creatures.
15:06
When you’ve thoroughly learned to walk and talk, your brain needs to throw out the walking and
15:10
talking manuals to make room for the more complex demands of existence. But just because all of this
15:15
is erased doesn’t mean that there’s no lingering traces in the foggy world of your adult mind.
15:21
Chapter Nine - The Ghost in the Machine
15:23
Of the many processes working in the brain at any one time,
15:26
only a few of them are actually conscious. Most are running on a kind of background tab,
15:31
even things that aren’t physical reflexes but learned skills like walking and talking. These
15:36
are called “procedural memories”, and they’re part of the larger subcategory of “implicit memories.”
15:41
This is the living legacy of your brain’s previous occupant, actions and reactions
15:46
rooted in your own deep history, things you do without really understanding why.
15:50
You’re nervous around dogs for no reason, but it was probably because a German Shepherd barked in
15:56
your face before you were 1 year old. You grow up having vaguely positive feelings about your
16:00
mother before you even really knew her, because of the bond you built before you were yourself. The
16:06
smoke is there, but the fire has long gone out. And all you can do is ask: Where did it all go?
16:12
Chapter Ten - The New Tenant
16:14
All of this ultimately proves the frightening truth we were hinting at at the start of the
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video: You - which is to say, the blob of ever-changing memories and flaring
16:23
synapses that decides by committee that it’s “You” - has always, in a sense, been you…
16:29
You just need to knock a few years off your age to get a truly accurate picture.
16:34
The first tenant of the fixer-upper you call your body, the one who learned to walk, who said this
16:39
body’s first words, who saw its first sunrise and sunset, is little more than a data ghost now.
16:45
A faint impression that appears in the back of your mind when you look at old photos,
16:49
or get told cute stories of your early years by your parents. They gave you everything,
16:55
and you killed them all just by coming into existence.
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So the next time you’re looking at your reflection in a mirror,
17:01
take a moment to remember that this reflection has never just been yours. Maybe whisper a little
17:06
“thank you” to the person who kept it warm for you for those first few years. Perhaps,
17:10
if there’s something after this, you’ll someday get to meet them.
17:14
Want to know more about the terrifying fragility of the human memory? Now check
17:18
out “A Man Went in for a Root Canal and Lost His Memory Forever”, or watch this instead!
