Today finished the movie, 'Paa'; that I started 2 days back (it’s another of my ideas, to rarely finish a movie in one sitting). 'Paa' is based on a rare condition called Progeria, an extremely rare genetic condition (1 in 8 million birth); where aging like symptoms are marked in relatively very early age. It’s a genetic condition that occurs as new mutation and is not inherited. [1]
As I was watching the movie, there was a question in my mind all the time. Auro, the character played by Big B, is a 13 year old kid suffering from Progeria. As in Progeria, though Auro is a kid, he looks like a very old guy, got glasses (though it’s not rare to find 13 year old having glass), is bald, has wrinkled skin and looks probably like a old Lilliputian guy. But interestingly, he behaves just like any 13 year old would do. He hangs out with guys of his age, he does things, plays and talks like a 13 year old. Does this means that though he is aging physically, his brain seems to be growing at normal pace. For once I thought maybe it’s another Bollywood flick, where you are not supposed to think too much and apply too much logic. But later I started looking about Progeria to find if it really does has no affect on the pace of brain growth.
I found few information about Progeria, but none that answered my question. I found characteristic symptoms include extreme short stature, early loss of hair, wrinkled skin, head disproportionately large for face, prominent scalp veins, low body weight, high-pitched voice, etc. that starts to show from 18-24 months. However, individuals retain normal mental and motor development. [2] [3] This is interesting to know; but then does it means that - though rest of physical body is deteriorating fast; brain which is also a physical lump of mass, does not deteriorates.
One interesting finding is related to the abnormal formation of lamin A protein caused by mutation in the gene known as lamin A (LMNA). The LMNA gene codes for two proteins, lamin A and lamin C, that are known to play a key role in stabilizing the inner membrane of the cell's nucleus. Abnormal formation of this protein seems to destabilize the cell's nuclear membrane in a way that may be particularly harmful to tissues routinely subjected to intense physical force, such as the cardiovascular and musculoskeletal systems. [3] But then does this explains all the symptoms of Progeria, or maybe there is more than this.
This does sound a good explanation for the causes of Progeria, but it does not seems to answer my question - does physical deterioration of brain occurs and if it does, why cognitive development is normal? So, I started my own thinking machine and came to following argument -
We are born with this physical mass sitting on top of our body, which grows in size as we grow old; but note that no new neurons are formed other than the ones we are born with. Interesting fact is, as a new born, we have the most number of neurons that we will ever have in our life. Because as we grow right as infant, many of the earlier neurons die. So a person with Progeria, should also have same brain capacity to start with as a normal human would. So Progeria person is not disadvantaged by not having grown enough neuronal count, because as said, even though he has Progeria, he is born with more neuronal count than he will have later in his life.
This physical lump, even when taken off a dead person, kept in some laboratory, showing no signs of life, doing no function and no neuronal firing, is still a brain. But when its working, its produces what we will call certain behavior, which in itself is the product of our mind. In simpler terms, mind is the product of the processing going on in the brain, that gets manifested into certain actions that we perceive as behavior.
A person with Progeria has a disorder where his physical body is deteriorating faster than that of a normal human being. So I assume that the physical brain might also be deteriorating and maybe at the same pace. But does that physical deterioration of brain has any affect on his mind, or eventually to his behavior. Maybe yes, but probably not too much. Our mind is created out of the physical connections, i.e. synapses between the neurons. Those synapses are different in different person, and formed mainly by a person's own experiences. And so does behavior changes, as the experiences change, as person grow old (not considering the hormonal changes).
In Progeria, the brain may be deteriorating, but mind is still evolving. Even in a normal person, as he gets old, his brain is definitely deteriorating, causing things like forgetfulness and hallucinations. But his mind might still be evolving, probably the reason why old guys are considered the most wise ones.
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