Evolutionarily speaking, why have we evolved such a large brain if we only use a fraction of it’s capacity??

Question

I understand that in space wise the electrodes pass through all of it but it is well known we are nowhere near using the full potential our brain holds. If you think otherwise try staring at the face of a watch/clock for 30 sec without taking you eye's off the sec hand and only thinking of it... Humans can only concentrate for a few seconds. Pretty weak huh...

Answer 1

That 'fractional use' wasn't discovered, it was hypothesized. That hypothesis has since been discredited. The idea probably started from observations of when neurons fire. But the brain works by parallel and associative processing. Picture 1000 students in an auditorium. The speaker announces, "Charles Smith, please stand up." How many students responded? The five who stood up? Yes, but also the 993 who listened, decided they were not Charles Smith, and stayed seated. Only the two who were asleep didn't respond.

That's a good metaphor for how the brain works. Each neuron continually 'listens' to its inputs. Once the state of the inputs matches its training, it fires. After a brief recovery period, it's ready to do it again. It doesn't matter what the rest of the brain is doing, it responds only to its inputs.

Intelligence is a measure of how well some of these processes work or are capable of working. Mental competence and performance is a function of intelligence plus training and practice.

Answer 2

So that people who use it more can be distinguished

Answer 3

We actually use *all* of our brains.

At any one time, only around 10% of the neurons in our brains are firing (any more and you're having an epileptic fit) - but which 10% varies from moment-to-moment. And if you average over time, we *do* use 100% of our brains!

> "I understand that in space wise the electrodes pass through all of it but it is well known we are nowhere near using the full potential our brain holds."

This is untrue.

Our *conscious* brains don't actually allow us to *consciously* process everything, because this process is extremely slow. But our subconscious brains are amazingly good at processing information!

For example, our eyes receive approximately 72 gigabytes of information *per second*, and our brains process *all* of that information (to say nothing of the constant stream of information from our other 10 senses). Our conscious brains only concentrate on a small portion of that (like the text on the computer screen you're reading), but your subconscious brain would still make you flinch if something was thrown at you from the side, in your peripheral vision - and it would do that before your conscious brain had even noticed it was there!

Think how difficult it would be if you actually had to concentrate in order to walk, or digest your food, or any of the million other processes your brain controls subconsciously.

> "If you think otherwise try staring at the face of a watch/clock for 30 sec without taking you eye's off the sec hand and only thinking of it... Humans can only concentrate for a few seconds."

Firstly, that's because that is not a useful process to be concentrating on. Our brains are "designed" to do other, much more useful tasks. Look up facial perception to see how our subconscious brains are so good at recognising faces that we'll see them when they aren't even there:

http://en.wikipedia.org/wiki/Face_percep...

This is so important for highly socialised animals like humans that it's "hard wired" into our neural structure.

And secondly, our brains are so amazingly adaptable that you can actually *train* your brain to be able to concentrate on the second hand, if that's what you want to do. Keep practising, and you'll be able to do it for longer and longer.

Answer 4

It's an urban legend that we only use a part of our brains. In fact, we use ALL of it.