The Brain — The Story of You

Namburi Srinath

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Many believe that the brain has the most complex design in the world (or maybe entire universe). Instead of validating whether it’s the most intricate design ever made by nature/God, everyone agrees to the point that the brain (Not just human brain!!) deserves a special place in evolution.

“If the human brain were so simple that we could understand it, we would be so simple that we couldn’t” — Emerson Pugh (Image source: Healthline)

So, what makes it so intricate despite the same carbon atoms that’s present in the rest of our body?

Is it the arrangement of atoms? If so, can’t we just tweak this arrangement and make a leg or a hand work as brain? Or, is it just the number of neurons and their synapse connectivity, strength? If so, can’t we simply map all the connections, simulate and reproduce identical copy (just as we take xerox of a paper)

In the book “The Brain — The story of you”, David Eagleman, a professor from Stanford University explains many concepts regarding brain succinctly and tries to answer why brain is unique. Anyone who is into AI, psychology, neuroscience or just fascinated to learn about YOU should pick this book.

Understanding brain

We humans are unfinished — Hardwired vs Livewired

A fish can swim immediately after birth. A giraffe can stand within hours after birth. If you observe, almost all the animals take very less time to develop their abilities. So, why do you think humans take so much time (years) in learning or acquiring basic skills?

Animals are preprogrammed (by evolution) so that it won’t take much time to learn the skills that’s required for their survival (fish can’t spare even few hours to learn how to swim). That’s called Hardwired and in most cases, it can’t be changed.

On the other hands, human brains are Livewired. While we don’t have too much program hard-coded during birth, we learn from environment and those experiences gets continuously imprinted on brain.

A very rough analogy with respect to computer science is that Hardwired ~ ROM (permanent) and Livewired ~ RAM (rewrite)

Most of us believe this preparedness (animal brain, as it’s brain already has contents) vs flexibility (human brain, as we continuously learn throughout life) trade off is what makes us special in this planet. But animals do learn a lot of skills (which we can’t). In a sense, there is no good reason to have a special place for human brain (if you believe it deserves special place, it’s from human perspective thus creating a bias)

Who am I? — A philosophical perspective

If you ask this question, some of the most popular answers you might reflect on are:

  1. I am my physical self: But then, “Within seven years, every atom in your body gets replaced by new ones”. So, your “physical self” is not a constant factor to measure who you are.
The “Ship of Theseus” is a thought experiment which attempts to answer the very same question of “Who am I?” in a different philosophical sense. (Check this video from TED: https://youtu.be/UHwVyplU3Pg) (Source: Blog)

2. I am an average of my memories: Ironically, your memories are also volatile (you feel more excited when you are doing skydiving rather than recollecting your act a year later). So, with your memories depending on the time, how can you say “I am ____” because it changes at every point in your life.

3. I am sentient (Experiencing/perceiving): But when you sleep, the neuronal activity is different (more synchronous, calm) from when you are awake (highly random)

So, “Who you are depends on what your neurons are up to, moment by moment”

What is reality? — We live in past

Observe this figure and comment whether A and B are same shade

Our brain constructs an internal model of the world and it simply re-calibrates based on what it sees on a daily basis. If it conflicts with our basic instincts (like seeing a flying panda), we become stressed out (But that doesn’t mean that it’s not real) (Pic: Checker shadow illusion)

It might be surprising to believe that A and B are the same shade (cover the rest of the image to test it). There are a ton of illusions focusing on this area which convey that we can’t blindly trust on our senses thus brings the necessity to doubt our reality.

Reality is not what’s happening outside but what’s happening inside.

Another concern with reality is we live in past. Suppose you touch a hot stove at t = 0. It takes some time (t~10ms) to feel that you are touching a hot stove and reflex. So, the moment you touched the stove (t = 0) has passed the moment you feel and acknowledge it (t ~ 10ms). (Image source)

“Human beings are works in progress that mistakenly think they’re finished. The person you are right now is as transient, as fleeting and as temporary as all the people you’ve ever been. The one constant in our lives is change.” — Dan Gilbert

Who is in control?

When you choose what dress you want to wear or what food you want to eat, do you really believe that you have total control on the decision that you made?

Your conscious mind is only the tip of the iceberg. Most of the decisions are taken by your unconscious mind. For example, try to count till 100 consciously i.e before uttering a digit, you need to acknowledge in your mind.

Shockingly, it’s a no. We believe that conscious brain controls us but it’s the unconscious brain that has overall control i.e it does tasks in background thus controlling conscious brain which controls us.

In a way, you didn’t have control in choosing your profession. During the first few years after your birth, your brain rewires rapidly removing many career options for you. It’s as if, you have many career choices like being a cricketer, actor, engineer, doctor, architect … and in those initial years because of rapid rewiring, it makes less probable in choosing one profession over another. In other words,

A rough analogy can be: In a bin (brain) there are a lot of papers (choices). Throwing of many papers (choices) eventually results in a single paper (career) in bin.

“You become who you are, not because of what grows in your brain but because of what is removed”

Some common questions

Are our eyes just a high-resolution camera?

Often, we see people comparing camera’s to our eyes. Many believe that a very high resolution camera can just function as eye. Is it true?

Sadly no. Eyes != High resolution camera because seeing is not just about photons hitting your eye. It’s a collective experience felt by body (Pic credits)

Researchers at MIT placed 2 kittens (A and P) in a vertically striped cylinder for few weeks after their birth with one kitten (P) placed in a box i.e can’t walk while the other kitten (A) can walk. Later in life, the kitten which was made to walk during the experiment (i.e kitten A) developed normal vision while the other kitten had difficulty.

Famous kitten experiment from Richard Held and Alan Hein, MIT. As the kittens were placed immediately after their birth, they couldn’t learn anything from environment and the only difference will be in experimental setup i.e both kittens are seeing the same visual input but one can walk while the other can’t. So, any difference in later life can be attributed to this walking impairment.

So, basically

Seeing → Seeing + Hearing + Smelling + Walking +Tasting + .. (and processing all these senses)

Why pistol is used instead of flashlight during races? — Neurological point of view

Have you ever wondered why pistol is used in races instead of flashlight. Well, a valid reason might be:

Most of the races occur during daytime and as it’s sunny, using light as a signal might not be a good idea. Or if it’s night, there will be lot of interference from flood lights.

Another reason why pistol is preferred is because of the initial heads-down position which gives an advantage for sprinters. (Image source)

But a neurological perspective can give more insights into this. We all know that light travels way faster than sound. But the visual system takes a lot more time than audio system to process (those who are into AI can understand it easier). So, it turns out that we respond faster to sound than light (difference is in order of milliseconds which is important in events like Olympics) thus making it as a preferred choice.

We usually acknowledge “seeing lighting before hearing bolt” to the fact that light travels faster than sound (t = 1ms and t = 20ms). But we also need to acknowledge the processing speed of complex visual (t = 1–10ms) to simpler auditory (t = 20–21ms) system.

Is it true that handicapped people have special abilities as shown in movies (Eg: a blind person can hear more clear etc;)?

Just imagine your brain as a collection book shelves and each shelf has it’s own functions (like a shelf for mystery books, a shelf for literature books etc;). Suppose you don’t have any literature books. Eventually, that shelf will be occupied by other genres.

The analogy that Brain → Book shelves is not exactly true. Different book shelves might not interact each other but different parts of brain are in constant interaction and that makes it more difficult to understand

In the same way, if the areas of brain that are associated with eyes doesn’t work (in case of blind), it will be eventually used by other organs thus improving their efficiency (but it might not be unrealistic as shown in many movies)

Why do we connect with actors in movies? (As in cry, laugh etc; when watching them)

Pain is processed in several parts of brain and the entire network is called pain matrix. Suppose someone slaps you. Starting from the interaction on your cheek till the pain is felt, all that processing is taken care by this pain matrix.

The moment someone slaps you (though it’s not good), there will a flow of information. Your cheek can feel some pressure variation, eyes process your opponent’s face and produces some signals → These signals are processed in various parts of brain including pain matrix → Outputs a feeling of pain on cheek (maybe tear signals to eyes if you are emotional) or turning on defensive mode in case it’s a fight

Research shows that watching someone else in pain i.e watching movies, reading novels activates this pain matrix. In other words, watching someone else in pain and you being in pain activates almost same neural connections.

So, the better the acting/writing skills are → The easier they can trigger our pain matrix.

In other words, this is empathy i.e being in other’s hat which is becoming a rare skill in modern world.

Some people say the bigger the head size is, the more intelligent they are. Is it true?

I don’t know whether it’s true or not but “intelligence” is a loosely defined term. And the best assumption might be:

Bigger head size → Might have more number of neurons → Might have more interactions between neurons thus strengthening → More skilled at what they do

Suppose I cut half the brain. Will it still work?

As our brains are livewired, it will figure out eventually what happened and will try to cope up (restore) as far as it can. So, surprisingly it’s a yes, though not advisable.

At the end of the day, all that matters is the quantity of quality interactions among neurons. (Source: pngkey)

Can we make a machine conscious?

The term consciousness has several definitions and is one of the most debatable topic. So, we shall stick to the basic definition i.e “subjective experience”.

All the experiences that we feel are nothing but the interactions of neurons (i.e electrochemical reactions in the subatomic levels). So, if we can replicate the pattern, yes we can make a machine conscious. But we have to answer some intricate questions as described by this hierarchical pyramid.

A hierarchical pyramid describing various questions present in the field of consciousness. Maybe, it takes a decade to fully understand and solve the really hard question i.e “Why is anything conscious?” ~ “Why evolution in the first place bought this one?” (Source: Life 3.0 by Max Tegmark)

P.S: Sleep research is another active area in psychology and some common questions are answered in this blog

Book suggested by Uday Girish Maradana

Further readings:

  1. Who am I?: www.brainpickings.org%2F2014%2F06%2F18%2Fdaniel-gilbert-happiness-future-self%2F
  2. The Ship of Theseus: https://www.brainpickings.org/2016/03/08/plutarch-the-ship-of-theseus-ted-ed/
  3. Kitten experiment: http://embodiedknowledge.blogspot.com/2011/12/classic-experiment-by-held-and-hein.html

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