"Redundancy" would be my first answer.
Most animal life on the planet has a majority of dual organs.
There is plenty of documentation of people being able to live after having half the brain removed, or having it get damaged.

Now, why the different halves of the brain seem to be linked to different types of thinking, stimuli and response, would be a really interesting question.

Great video. Savants always impress me with their abilities. Just amazing what they can do.

"Is there a good reason the brain has a right side and left side? Why cant it just be whole?"

To divide tasks like a dual core processor in a computer. It seems to be more efficient and effective that way. It might also have to do with binary, the most basic number system in the universe and in nature. It could also do with consciousness, maybe two mirrored points must be compared for self awareness and identity. Or, simply it just turned out that way, or God(if real) could have designed it for internal conflict.

I didn't watch the movie yet, I might later. The above is just my random speculations on the question and is unrelated to the video linked.

[edit on 16-7-2007 by halfmask]

I read somewhere that it was evolutionary but I don't remember the specifics of it.

If you look at the Brain as a 3D object you can see that it is actually split into lots of little different zones. Many of the zones span the hemispheres and some areas exist only in one.

Also, cerebrospinal fluid (CSF) has to be able to move freely and efficiently around the brain and fill the ventricles. The CSF is the extremely dense fluid that supports the brain and acts as a sort of shock absorber. Also, if you were to be struck in the side of the head you would damage one hemisphere and the CSF inbetween the hemispheres could help prevent severe damage to the other. Memory and motor control are evenly split across the two. Speech and language are situated in one hemisphere.

If you damage the speech centre of your brain it can be taken up by an entirely separate section of the brain and can redevelop, the same is true of many brain functions which exist only on one hemisphere.

And then theres theories regarding your skull developing as an infant. The brain may grow faster under the protective surface of the infant skull sections which float, unjoined, on top of it.

Of course theres the argument that it just turned out that way, two is better than one.

Originally posted by Horrificus
"Redundancy" would be my first answer.

That is the best answer, and is further supported by the fact the brain is crosswired with the body such that the left side of the brain controls the right side of the body and vice versa.

People born with a badly diseased side of the brain can have it removed without any ill effects and the positive effects of stopping seizures, etc.

If half the brain becomes damaged later in life, the other side of the brain usually takes over its functionality after time and rehabilitation as the nervous system rewires itself to be governed mainly by just one hemisphere.

In some cases of epilepsy, instead of removing half the brain, simply the narrow connective bundle of nerves between the hemispheres is cut (the corpus callosum), leading to some very bizarre results in some experimental psychological tests, it's almost like two people in one body.

[edit on 7/16/2007 by djohnsto77]

[edit on 7/16/2007 by djohnsto77]

The brain has two halves in the same way that there is both night and day, male and female, positive and negative etc.. Both parts are needed to form the trinity, the third component, like the "holy spirit", the colour grey, a solar eclipse etc.. Just by having two "opposites" or potentials, you give rise to the third form.

As to why we have two halves, and not one, is to do with the way we develop, and the way all of reality develops, through sacred geometry.

The left half of the brain controls the right side of the body, and vica versa. The left side of the brain is the male component, and the right is the female. The male side is the logical, and sees everything absolutely logically, whilst the female side is more concerned with experiencing something than understanding it.

There is also a subdivision of the two halves also, meaning that one half has both the experiential component (female) and the logical component (male).

So, the left side is the male half; Its front subdivision is the "geometrical logical" portion, and the back is the "male experiential".

On the right side is the female half; Its front subdivision is the "female experiential" portion, and teh back is the "geometrical logical" component "female".

So basically there are 4 portions, not just two halves..

But even more importantly is the connection between all of these, aswell as the third eye, which resides right in the centre of the brain, the so called "seat of the soul". When someone becomes "enlightened", they can utilise both sides of the brain without bias, and the third eye becomes fully active, uniting the entire brain into one.

The final point that needs to be made is that the brain is holographic. Every point contains the whole.. just like the entire universe aswell An series of experiments done on salamanders, where they removed the brain, switched it around, cut bits out, and did all kinds of tweaking, resulted in no difference to the creatures ability to remember and proceed with its every day tasks..

This is because the information it has learnt is holographic, and can be retrieved from any portion of the brain. The brain is not concerned with memory in truth, but the "acting", the conscious participation in reality. Memory is something far more interesting.. and the word itself aswell (water-light, liquid light), and its connection to DNA also.

Nerdling pretty much said how I was going to answer your question so I will just give my 2 cents about some autistic savants rare abilities.

Children and adults with autism usually have parts of their own brain which do not function normally or are underdeveloped. This gives way to the rest of the brain making up for the lack of development in a certain area by stimulating tremendous growth in other areas. Thus, we have all probably heard of savants that can paint entire cities by memory (like in the video provided), or can memorize Pi to 20,000 decimal places, and other rare talents. Make no mistake these are tremendous abilities, but anyone is capable of the same thing if you develop areas of your brain and neglect other areas.

Now, I'm going to make an example of myself for lack of better comparison, but I personally have learned over time to recognize and develop my sense of hearing to the point that I can play almost anything by ear after I hear it once. If I hear sounds in nature or on a record I can play them on an instrument almost after the first time listening to them. This does not mean that I am a savant or have some "miracle" brain, but rather I developed it through intense study...in savants it is developed out of need and survival...not will. The social, physical, and subconscious areas of my brain do not have to make up for other areas as a savant would, leaving "normal" people greater overall functionality. There are plenty of cases of the exact same thing in the arts, mathematics, social sciences, etc. Savants, on the other hand, have fine tuned one part of their brain to deal with the development of another area...it's a Tug-of-War survival game.

In other words, the abilities of savants come from a "compensation" factor that re-balances the brain. We use nearly 100% of our brain power at any given time, and it is evenly balanced between motor function and thought function, but when a brain is injured or underdeveloped in a certain area the rest of the brain will make up for it so we don't lose our 100% functionality. Don't get me wrong the abilities of such people are fantastic and awe inspiring, but are merely a part of human reaction and ability of survivial when faced with underdevelopment or adverse injury.

This is because the information it has learnt is holographic, and can be retrieved from any portion of the brain. The brain is not concerned with memory in truth, but the "acting", the conscious participation in reality. Memory is something far more interesting.. and the word itself aswell (water-light, liquid light), and its connection to DNA also.

Sorry to repeat myself, but can i ask how you all feel about this paragraph?? I never seem to get responses to these bits, and i just want to outline it before its forgotten to the thread;

Do you believe that the consciousness, YOU, resides in your brain, that your brain controls your body, and that it is the top guy in the chain of command, so to speak?

Whilst i see that certain areas show activity when thinking or doing certain things on an EEG, does that really mean that the brain is actually making these commands or sequences of motion?? What im trying to get at is, is there really any basis for saying the "doing" part of you is in the brain?

In relation to austism, do you think that these peope are gifted, impaired, or otherwise? Or do you think they are just like any other person, but simply have another portion of their brains "unlocked".. or "disabled". For me, i would say they are gifted, because i believe memory is not something concerned with the brain itself. I see the brain as a reciever for information, not a just sender.

Is it me, or does the narrator of the clip sound like Stuie from Family Guy?