The immediate insight
that I take from this item is that cognition is about operating an association
engine. What this also means is that
smart and fast is helpful but not particularly critical unless speed itself matters. Of course our education forces speed as a
primary trait and short changes slower processors. This supports my own observation that some
very smart people come across as somewhat slow in external presentation. I never had that problem but learned to
appreciate slow and methodical more even than speed as a key trait that needs
support.
The associative skill
demands clarity and content. A skilled
thinker will gather data and make sure that he gets it right as much as
possible. The key that is missing in
most discussions is the need for a steady supply of valid data and skilled
interpretation.
Thus if your ambition is
to be the smartest chap on the block it is not only necessary to train the mind
but to also steadily gather data and associated inferences. This can never be attained in a handful of
years but must be attended to throughout a lifetime.
The Human Brain Is A
Tangled Clump Of Wires But A New Theory Suggests That's Why We Are So Smart
JAN. 8, 2014,
The complexities of the human brain are what
make humans such a unique species. But how our brains end up so different from
those of other mammals?
Scientists have long linked a bigger brain size to higher
intelligence, but scientists are still not sure why.
Two neuroscientists have proposed a new theory in a paper
published in Trends in Cognitive
Science in December.
Their theory proposes a possible reason why a bigger brain makes
humans smarter. The scientists believe that as the human brain grew and
expanded, neuron connections were pulled apart and the extra space allowed for
a greater number and more complex neuron connections to form.
How big the human brain is
On a scale relating brain size and body size of different species,
the human brain is about five times the size it should be if we followed the
trend set by other mammals.
You can see how much the human brain stands out from the brains of
other mammals in the image below:
###
Trends in Cognitive
Science/Buckner, Krienen
You can see how quickly the human brain grew as
hominids evolved over time in the chart below.
Humans and chimpanzees are closely related, and
in the early stages of development, chimpanzees and humans have a similar brain
to body size. But the human brain continues growing much longer than a
chimpanzee's brain. Human brains also have many more neurons than other animal
brains. A whale brain is more than double the size of a human brain, but
actually has fewer neurons than a human brain, the researchers write.
The Tether Theory
The scientists, Randy Buckner and Fenna Krienen from Harvard
University, have proposed a simple explanation — which they've named the
Tether Theory — for how these larger brains made humans smarter.
Simply having a large brain with lots of neurons does not explain
modern human intelligence. Our recent ancestors had similar brain sizes but
lacked the ability to build civilizations and understand modern technologies.
The scientists think the processes that the brain went through while evolving
to be larger is the most important part.
Early human ancestors and most other mammals' brains are wired
with straightforward circuits that pick up information from the surrounding
environment through the senses and relays that information to motor neurons so
the body can move and respond to the surrounding environment. One example in
humans is when we touch something hot and automatically jump back. This is
called the sensory-motor pathway. In these smaller brains, the neurons were
physically close together.
But the researchers have proposed that as the human brain
expanded, some of these simple sensory-motor pathways were pulled apart and
came untethered, making room for more complex circuits to develop within the
connections.
###
Trends in Cognitive Science
This image shows a Macaque and Chimpanzee brain. The colored areas
of the brain show where the human brain is larger and specifically how many
more times larger. The inset of the chimpanzee brain shows the primary visual
area of the brain.
These complex circuits form in the association
cortex, the area of the brain that separates humans
from other animals; the neuron connections that form there are responsible for
higher mental processes like thought and memory.
In the image to the left you can see how many times more expanded the
association cortex of the brain is in humans compared to a macaque and a
chimpanzee.
These circuits, unlike the sensory motor pathway, don't form in a
straight line where the signal travels from one neuron to its immediate
neighbor. Instead, circuits in the association cortex link neurons that are
both close together and far apart, almost like a tangled clump of wires.
You can see the difference in the image below. The simple
sensory-motor pathway is on the right, and the more complex association pathway
is on the left.
###
Trends in Cognitive
Science/Buckner, Krienen
The neurons and circuits in the association
cortex don't rely on input from the outside environment. That's why as humans
we are able to think introspectively and learn about ourselves — a trait called
meta-cognition.
The scientists hope to test their theory by comparing the human
brain to the brains of other animals that haven't been completely mapped yet,
like the chimpanzee.
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