ject has not been old people but the importance of exposing the brain to stimulation, challenge, change, ambiguity, nov- elty - an enriched environment. All evidence indicates that whether we are twenty, forty, or eighty our brains have the capability of growing, and we have the ability to become more intelligent. In fact, the evidence indicates that the more you learn, the greater is your capacity for further learning. The more you put into your memory, the more powerful your memory becomes. Without sufficient stimulation, however, this growth will not happen; in fact, our minds and brains will deteriorate, no matter how young or old we are.
When the Berkeley researchers first began studying the re- lationship between sensory stimulation (or learning) and phys- iological brain growth, they put their rats in three environments. Later research with a "super-enriched" environ- ment produced even greater brain growth than the enriched environment. This raised a question. Just how much can a rat's cortex grow? Where are the limits? Researchers created a "seminatural" outdoor environment and found that the rats raised there showed even greater brain increases than in the super-enriched environment. Recent studies of squirrels raised in a feral or fully natural environment indicate that in many brain measures, such as brain RNA per unit of brain weight, the feral squirrels are significantly higher than squirrels raised in an enriched laboratory environment. Where will it end?
In each case, increases in environmental complexity lead to increases in brain growth. We can imagine the possibility of devising some sort of "super-mega-enriched" environment that would produce even greater brain growth in rats and squirrels than their natural wild environment. What the scientists area beginning to do, step by step, is learn how to make a superior brain.
There can be no doubt that this research has important im- plications for humans. We know that environmental factors
4 8
THE W I S D O M OF AGE
are enormously important in brain development. For example, University of Arizona professor Samuel A. Kirk claims that given a certain amount of brain at birth, a person's intelligence may vary up to 40 IQ points as a result of different environ- ments. Recent studies have shown that adults with low IQs, "retarded" since birth, when given challenging educational or life experiences can "outgrow" their low IQs and gain average or above average intelligence.262
And just as the octogenarians who are cruising through marathons are constantly challenging our concept of the limits of the human body, these humans who continue to grow men- tally into old age are reminders that we - and scientists - have yet to discover the limits of human brain growth. Surely, like those rats placed in the"super-enriched" environment that showed as much brain growth in four hours as the enriched environment rats showed in a month, there must be some human super-enriched equivalent. Could the mind machines, by subjecting the brain to intense amounts of stimulation, have that sort of hothouse effect, force-feeding enrichment to our neurons and triggering rapid brain growth?
Interestingly, one technique used with enormous success to reverse aspects of brain decline in old people has been ma- chines. Aging people challenged by computer video games like Pac-Man and Space Invaders have been found to show significant mental improvements. Other machines, a number of which I will describe, have been used to stimulate direcdy the brains of humans with a variety of neurological problems, including Down's syndrome, mental retardation, and learning disabilities; the subjects have responded with astonishing re- coveries of mental abilities or sharp increases in a variety of brain values.
The thrust of this book is to examine these machines not as therapeutic devices capable of bringing subnormal or sick brains to a state of normality or health, but rather as tools for stimulating already healthy brains and spurring them into greater-than-normal growth, higher-than-ordinary capabilities. What are the limits to brain growth? No one yet knows. As author George Leonard expressed it in his Words of awe at the
MEGABRAIN
WHAT THIS CHAPTER IS REALLY ABOUT
WHILE THIS CHAPTER HAS FOCUSED ON AGING, THE REAL SUB-ject has not been old people but the importance of exposing the brain to stimulation, challenge, change, ambiguity, nov- elty - an enriched environment. All evidence indicates that whether we are twenty, forty, or eighty our brains have the capability of growing, and we have the ability to become more intelligent. In fact, the evidence indicates that the more you learn, the greater is your capacity for further learning. The more you put into your memory, the more powerful your memory becomes. Without sufficient stimulation, however, this growth will not happen; in fact, our minds and brains will deteriorate, no matter how young or old we are.
When the Berkeley researchers first began studying the re- lationship between sensory stimulation (or learning) and phys- iological brain growth, they put their rats in three environments. Later research with a "super-enriched" environ- ment produced even greater brain growth than the enriched environment. This raised a question. Just how much can a rat's cortex grow? Where are the limits? Researchers created a "seminatural" outdoor environment and found that the rats raised there showed even greater brain increases than in the super-enriched environment. Recent studies of squirrels raised in a feral or fully natural environment indicate that in many brain measures, such as brain RNA per unit of brain weight, the feral squirrels are significantly higher than squirrels raised in an enriched laboratory environment. Where will it end?
In each case, increases in environmental complexity lead to increases in brain growth. We can imagine the possibility of devising some sort of "super-mega-enriched" environment that would produce even greater brain growth in rats and squirrels than their natural wild environment. What the scientists area beginning to do, step by step, is learn how to make a superior brain.
There can be no doubt that this research has important im- plications for humans. We know that environmental factors
4 8
THE W I S D O M OF AGE
are enormously important in brain development. For example, University of Arizona professor Samuel A. Kirk claims that given a certain amount of brain at birth, a person's intelligence may vary up to 40 IQ points as a result of different environ- ments. Recent studies have shown that adults with low IQs, "retarded" since birth, when given challenging educational or life experiences can "outgrow" their low IQs and gain average or above average intelligence.262
And just as the octogenarians who are cruising through marathons are constantly challenging our concept of the limits of the human body, these humans who continue to grow men- tally into old age are reminders that we - and scientists - have yet to discover the limits of human brain growth. Surely, like those rats placed in the"super-enriched" environment that showed as much brain growth in four hours as the enriched environment rats showed in a month, there must be some human super-enriched equivalent. Could the mind machines, by subjecting the brain to intense amounts of stimulation, have that sort of hothouse effect, force-feeding enrichment to our neurons and triggering rapid brain growth?
Interestingly, one technique used with enormous success to reverse aspects of brain decline in old people has been ma- chines. Aging people challenged by computer video games like Pac-Man and Space Invaders have been found to show significant mental improvements. Other machines, a number of which I will describe, have been used to stimulate direcdy the brains of humans with a variety of neurological problems, including Down's syndrome, mental retardation, and learning disabilities; the subjects have responded with astonishing re- coveries of mental abilities or sharp increases in a variety of brain values.
The thrust of this book is to examine these machines not as therapeutic devices capable of bringing subnormal or sick brains to a state of normality or health, but rather as tools for stimulating already healthy brains and spurring them into greater-than-normal growth, higher-than-ordinary capabilities. What are the limits to brain growth? No one yet knows. As author George Leonard expressed it in his Words of awe at the
MEGABRAIN
incredibly vast potentials of interaction between neurons, "A brain composed of such neurons obviously can never be 'filled up.' Perhaps the more it knows, the more it can know and create. Perhaps, in fact, we can now propose an incredible hypothesis: The ultimate creative capacity of the brain may be, for all practical purposes, infinite."195
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