Why do we only use roughly 10% of our brains?

Name:Fat Man; Date:August 9, 1945;
Operation:?; Site:Nagasaki, Japan;
Detonation:Air Delivered; Yield:21.00kt; Type:Fission,Pu239;
US detonated second nuclear bomb during the WW II, at this time over Nagasaki, Japan. The bomb named Fat-Man was detonated at 11:02 am. at an altitude of 1500 ft. Yield 21Kt. Of the 286,000 people living in Nagasaki at the time of the blast, 74,000 were killed in an instant, and another 75,000 sustained severe injuries.
Fat Man was identical to the Gadget device used in the Trinity test, except it was encased in steel. Ostensibly, Fat-Man used Pu239 instead U235 and more efficient, implosion type design. It measured 60 inches in diameter, was 12 feet long, and weighed 10,300 lb. All the parts for the Fat Man assembly finally arrived at Tinian by Aug. 2, 1945.
The delivery date has been shifted several times due to changing weather conditions. Finally the date was set, Aug. 9. 1945. Primary target for the bombing has been an arsenal in the city of Kokura. B-29 arrived at the target zone around 10:44 am. However clouds, flaks and fighters prevented it from precise bombing and it had to rout towards the secondary target. One more problem was the malfunctioning fuel pump, which rendered a 600 gallon auxilary tank useless. That in turn limited the choice of the secondary target, so B-29 set the course towards Nagasaki. When the bomber arrived at Nagasaki the remaining fuel would only allow it one pass over the city for bombing, even with emergency landing at Okinawa.
The only gap over the area permitted a drop, which missed the original aimpoint by several miles. The detonation occurred near the city perimeter, close to Mitsubishi arms plant. Despite the fact that Fat Man fell closer to an unpopulated area the casualties were immense, 42,000 died in an instant and 40,000 more were injured. 39% of the city buildings were destroyed.
Delivered by B29 Bomber Bock's Car, crew:
Major Charles Sweeney - Commander; First Lieutenant Charles Albury - Co-Pilot;
Captain James Van Pelt, Jr. - Navigator; Captain Kermit Beahan - Bombardier;
Lieutenant Jacob Beser - Electronic Countermeasures; Staff Sergeant Ed Buckly - Radar Operator;
Sergeant Abe Spitzer - Radar Operator; Master Sergeant John Kuharek - Flight Engineer;
Sergeant Raymond Gallagher Asst. Flight Engineer; Staff Sergeant Albert Dehart - Tail Gunner;
Commander Frederick Ashworth - Weaponeer; 2nd Lieutenant Fred Olivi - Third Pilot;

I don't think we use our brains at all!

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MJA

A japanese officer drags out a prisoner from the ranks of starving men for daring to look at him .The man has survived two years of terrible punishment by this officer, he has seen his comrades die one by one, very very slowly..The officer forces the man to his knees and takes his sword out and with grin chops the prisoners head off in one blow . The officer kicks his head away, gestures to the other prisoners to bow in submission..Captain Brown who i worked with after ww2 told that story to me.The brain is capable of many things..

Another terrible example of far less than 10%!

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MJA

I thought too of it and have come to a conclusion that God has disposed very reasonably. The matter is that used neurons wear out and can perish or reduce quantity neuron processes because of aggressive influence of an environment. At neurons which are used in thinking, the metabolism is accelerated faster proceeds, that is the metabolism, than at neurons, being in a reserve. Frequent use same neurons results to deterioration, because of meal and ecology. Even the purest meal contains some share of toxins rather harmless for neurons. But all the same deterioration or destruction neurons takes place. And the brain as though keeps other part in reserve when used sites of a brain become not suitable the brain includes instead of them others neurons which were before in a reserve. If the person uses all neurons, for thinking the person use up all neurons and quickly would come to worthlessness.

from what i've heard, one of the biggest limiting factors for our brains is the amount of nutrients its capable of getting. if we were able to get more food and oxygen to our brains, we could vastly improve our cognitive capabilities. i'm not saying that the 10% thing is true, but that our brain could potentially be more powerful if it wasn't for the limit on how much energy our bodies can use on it.

Yes, the amount of nutrients and oxygen plays large role. But in the course of brain work, products of ability to live of a cerebral tissue which accumulate are developed and poison the cerebral tissue of brain. Because, bad blood supply does not allow to work at full capacity separate sites of a brain. Toxins should leave and neurons should be filled with fresh blood. Even using sites of a cerebral cortex can not reveal on full power, because of bad blood supply.

You can observe it, when pupils at school's lesson which are attentive in the beginning and well study, and then they would like to sleep. There comes exhaustion because of the accumulated toxins in an active part of a brain, and the brain gives a command on a dream or switches work of a brain from one sites to other sites. Therefore pupils at school start to think about something other things.

There are pupils which like to be engaged in hours in mathematics, but at once get tired and lose interest at a literature lesson. At such pupil cerebral cortex sites participating in mathematical thinking are well developed, there likely large blood vessels which well supply cerebral tissue with oxygen and nutrients and carry away an excretory products . And cerebral cortex sites participating in literary thinking they are badly developed, likely there averages on diameter blood vessels which cannot react to activity of these neurons, to delivery plenty amouts of oxygen and nutrients, and tap of a waste from a metabolism. And these certain sites of a brain choke in toxins. If the mathematician periodically trains itself being engaged in the literature intensively, this person will love the literature too.

Usually blood vessels are formed in the childhood, frequent thinking and certain associations, allow to develop strongly to separate sites of a cerebral cortex and bad another cerebral cortex sites.

I think we only use ten percent of our brains becase it only takes 9% to get laid, and 1% to get fed...It is a simple matter of economy...But get caught eating crackers with some other guy's wife, in bed, and you will find all your neurons firing at just about the same instant you hear him walk in the door...
It reminds me or a joke: This Carpenter was in bed with a woman, and she hears her husband pull in the drive... She says: that's my husband, and he wasn't due home until tomorrow... The wood butcher was pulling on his drawers, and he said: where is the back door... She said: We don't have a back door...He say's: fine; where would you like a back door????