There is a perpetual myth about the brain that we do not use
it fully to its capacity and that if we start using it to the fullest we might be able to
move objects at our will. The ‘Network’ that it is, the brain is not
hardwired, David Eagleman contends it is livewired. With his new theory of
infotropism, he demonstrates why the fundamental principle of the brain is
information maximization: in the same way plants grow toward the light, brains
reconfigure to boost data from the outside world.
There is new insight into how the brain can ‘re-pair’ or adapt to new circumstances. This is very close to what we have been discarding lately – ‘evolution theory’. The author starts his narration with a case of a child who can function with one-half of his brain removed, how a blind man can hit a baseball via a sensor on his tongue, how new devices and body plans can enhance our natural capacities, and how paralyzed people will soon be able to dance in thought-controlled robotic suits.
Here are some highlights of the book in the order it goes.
#As we grow, we constantly rewire our brain's circuitry to take challenges, leverage opportunities and understand social structures. The brain consists of 86 billion neurons that shuttle information - 20 times more connections in a cubic centimeter of tissue than the entire Earth’s population. This amounts to adaptability.
“Unconscious actions are more rapid than conscious liberation”.
The brain’s plasticity or neuroplasticity is discussed in a few case studies
and the conclusion was that it would hold and keep the information forever if
needed. When you compare this ‘memory’ with the electronics, you cannot slice
out half of them from your smartphone and hope to make a call - Livewire
endures!
“Brains are not born as blank, instead they arrive pre-equipped
with expectation and the growth of the brain is based on the environment”. So, what we
bequeath is more from our ancestors, and rather refined. Research on monkey nerve
severed arm did not respond in the cortex but after some months this area was
found to get excited when a part of the face was touched. The brain's map is thus flexible.
Phantom Limb, a subject of many a neurosurgeon, has found a
mention but with meta-physics- “if an absent limb could give rise to conscious
feeling then an absent body might as well”. So where do we go after we die?
An accomplishment of the rewiring is mentioned with an instance
of Ronnie, born blind who used other senses to master music – violin - and won as
many as six Grammy awards!
Competition for brain cells ‘real estate’, is that our visual
system has to deal with darkness for almost 12 hours (from sunset to sunrise). To
counter this the brain’s occipital cortex keeps itself active during the night and
thus dreaming exists to keep the visual cortex from being taken over by
neighbouring areas. And here we have so many interpretations for a dream that merely shuffles the memories! The hippocampus and prefrontal cortex are less
active during dream sleep than during walking state. Thus we cannot remember
dreams, perfectly.
A hypothesis about cochlear and retinal implants read as the “Potato head hypothesis” where plugging into sensory organs the brain figures out how to use them!
Another research by Nobel Laureate goes as “Vision
substitution by Tactile Image projection” in nature - by Bachy-Rita – Here the
brain is able to use information coming from the skin as if it were coming from
the eyes! Different types of information are found lurking in different regions
and the one for vision hearing has a case study. The skin is a mind-boggling sophisticated
computational material!
Bauby, an editor of Elle magazine suffered a stroke and could
only move his left eyelid. He was able to communicate with the aid of therapists
and he thus relayed the agony of being unable to interact with the outside
world.
All new ideas in the brain come from a mash-up of previously learned inputs and today we get more new inputs than before as children now live in an unparalleled richness.
The discussion about ‘illusion’ takes up some significant
space. The brain considers walking as ‘real’ as walking over a treadmill just
conveys the stationary fact by the vision. The IBM logo finds a mention due to
its illusionary appearance. The Troxler effect is an illusion that demonstrates
that an unchanging stimulus in your peripheral vision will soon evaporate so
that the parts of the invisible would be obvious to us. Imagine cosmic rain
that exists and is invisible. If it is stopped it might give you vision
otherwise!
How drugs modify our system is another area of discussion.
The drugs change the number of receptors in the brain - so much that the analysis
of the dead brain can be used to determine the deceased’s addiction. Neural prediction
is mentioned as “People you love become part of you - not just metaphorically
but physically”.
The strategy of bacterial movement when searching for some food was
interesting to read as how they group and have an objective for movement.
The cognitive area gets sharpened by learning a new language.
The language is localized on the left hemisphere and if the left side of the brain
comes under the stroke, the person may no longer be able to speak or understand words.
The brain figures out the body map from a simple rule!
The areas that send the most information with the largest
representation!
Benefits of a good death:
An example is a sculpture carved out from marble. Creation emerges by
taking stone away, not by adding anything. Similarly, neurons look for the right place.
They put in feelers. If they’re getting a good response they keep it going. If
they get cold shoulder they try luck nearby with other neurons (they get the message
that they do not belong)! Thus training for anything new is very significant!
Cell death, apoptosis (suicide), and necrosis (inflammation)
are briefly discussed as chemical leak out that can damage neighbourhood but is not
a bad thing as it is considered as an engine for sculpting a neuron system!
Saving Brain Forest (re-wired brains, particularly) is
compared to rain forest because the neurons are like members of a forest/network
which are in constant competition to stay alive!
Every man is born as many men and dies as a single one.
The habits we form from childhood make no small difference,
but rather they make all the difference - Aristotle
Brains plasticity is a form of generic expression, for
example, the skin pigment genes are variable because humans find themselves at
different altitudes and need to change pigmentation to absorb vitamin D!
The enemy of memory is not time, it is other memories. Reading
a new book does not overwrite your spouse's name in your memory nor does learning a
new vocabulary word makes the rest of your vocabulary worse.
The brain passes what it has learned to another area for
more permanent storage.
Memories beautify life, but only forgetting makes it
bearable - Honore De Balzac
Different kinds of memory: With each new thing we learn, the
better we are able to absorb the next relative fact. The last part of the book
is more of a technical aspect including how the brain can be trained and memory
or performance be enhanced. The amazing network and memory are discussed
brightly and the book made an excellent read.
No comments:
Post a Comment