What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic

 

What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic 

 

 An enduring myth says we use only 10% of our brain, the other 90% standing idly by for spare capacity, Hucksters promised to unlock that hidden potential with methods "based on neuroscience," but all they unlock is your wallet. 

 

What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic

 

 Two-thirds of the public and nearly half of the science teachers mistakenly believe the 10% myth, in the 1890s, William James, the father of American psychology, said, "Most of us do not meet our mental potential," James meant this as a challenge, not an indictment of scant brain usage, but the misunderstanding stuck, also, scientists couldn't figure out the purpose of our massive frontal lobes in broad areas of the parietal lobe for a long time, The damage didn't cause motor or sensory deficits, so authorities concluded they didn't do anything, for decades, these parts were called silent areas, their function elusive, we've since learned that they underscore, executive, and integrative ability, without which, we would hardly be human, they are crucial to abstract reasoning, planning, weighing decisions, and flexibly adapting to circumstances, the idea that 9/10 of your brain sits idly by in your skull looks silly when we calculate how the brain uses energy.

What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic 

 

 Rodent and canine brains consume 5% of total body energy, monkey brains use 10%, and an adult human brain, which accounts for only 2% of the body's mass, consumes 20% of daily glucose burned, in children, that figure is 50%, and in infants, 60%, this is far more than expected for their relative brain sizes, which scale in proportion to body size, Human ones weigh 1.5 kilograms, elephant brains 5 kg, and whale brains 9 kg, yet on a per-weight basis, humans pack in more neurons than any other species, this dense packing is what makes us so smart, there is a trade-off between body size and the number of neurons a primate, including us, can sustain, a 25 kg ape has to eat 8 hours a day to uphold a brain with 53 billion neurons, the invention of cooking, one and half million years ago, gave us a huge advantage, cooked food is rendered soft and

What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic 

predigested outside the body, our guts more easily absorb their energy, cooking frees up time and provides more energy than if we ate foodstuffs raw, so we can sustain brains with 86 billion densely packed neurons, 40% more than the ape, here's how it works, half the calories a brain burns towards simply keeping the structure intact by pumping sodium and potassium ions across membranes to maintain an electrical charge, to do this, the brain has to be an energy hog, it consumes an astounding 3.4 x 10^21 ATP molecules per minute, ATP being the coal of the body's furnace, the high cost of maintaining the resting potentials in all 86 billion neurons means that little energy is left to propel signals down axons and across synapses.

What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic

 The nerve discharges that get things done, even if only a tiny percentage of neurons fired in a given region at one time, the energy burden generating spikes over the entire brain, would be unsustainable, here's where energy efficiency comes in, letting just a little proportion of cells signal at one time, known as sparse coding, uses the least energy but carries the most information because the small number of signals have thousands of possible paths by which to distribute themselves, a drawback of sparse coding within a large number of neurons it cost worse, if a large proportion of cells never fire, then they are superfluous and evolution should have jettisoned them long ago.

 The solution is to find the optimum proportion of cells that the brain can have active at once, for maximum efficiency, between 1 % and 16 % of cells should be active at any given moment, this is the energy limit we have to live within order to be conscious at all, the need to conserve resources is the reason most of the brain's operations must happen outside of consciousness.

What percentage of your brain do you use? How much the Human Brain is smart and powerful? How does the Brain Work? Richard E Cytowic

 

It's why multitasking is a fool's errand, we simply lack the energy to do two things at once, let alone three or five, when we try, we do each task less well than if we had given it our full attention, the numbers are against us, your brain is already smart and powerful, so powerful that it needs a lot of power to stay powerful, and so smart that it has built-in an energy-efficiency plan, so don't let a fraudulent myth make you guilty about your supposedly lazy brain, guilt would be a waste of energy, after all, this, don't you realize it's dumb to waste mental energy? You have billions of power-hungry neurons to maintain.