The Brain That Changes Itself (9)

Merzenich claims that when learning occurs in a way consistent with the laws that govern brain plasticity, the mental "machinery" of the brain can be improved so that we learn and perceive with greater precision, speed, and retention.

The Brain That Changes Itself (8)

Enriched environments and stimulation lead the brain to grown. Over the years his labs and others have shown that stimulating the brain makes it grown in almost every conceivable way. Animals raised in enriched environments --- surrounded by other animals, objects to explore, toys to roll, ladders to climb, and running wheels --- learn better than genetically identical animals that have been reared in impoverished environments. Acetylcholine, a brain chemical essential for learning, is higher in rats trained on difficult spatial problems than in rats trained on simple problems. Mental training or life in enriched environments increases brain weight by 5 percent in the cerebral cortex of animals and up to 9 percent in areas that the training directly stimulates. Trained or stimulated neurons develop 25 percent more branches and increase their size, the number of connections per neuron, and their blood supply. These changes can occur late in life, though they do no develop as rapidly in older animals as in younger ones. Similar effects of training and enrichment on brain anatomy have been seen in all types of animals tested to date.

孟母三迁的生理学原因。看来创造环境对孩子的成长是十分必要，也是非常重要的。

The Brain That Changes Itself (7)

Barbara Arrowsmith Young's work compels us to imagine how much good might be accomplished if every child had a brain-based assessment and, if problems were found, a tailor-made program created to strengthen essential areas in the early years, when neuroplasticity is greatest. It is far better to nip brain problems in the bud than to allow the child to wire into his brain the idea that he is "stupid", begin to hate school and learning, and stop working in the weakened area, losing whatever strength he may have. Younger children often progress more quickly through brain exercises than do adolescents, perhaps because in an immature brain the number of connections among neurons, or synapses, is 50 percent greater than in adult brain. When we reach adolescence, a massive "pruning back" operation begins in the brain, and synaptic connections and neurons that have not been used extensively suddenly die off --- a classic case of "use it or lose it". it is probably best to strengthen weakened areas while all this extra cortical real estate is available. Still, brain-based assessments can be helpful all through school and even in college and university, because their week brain functions are overloaded by the increased demand. Even apart from these crises, every adult could benefit from a brain-based cognitive assessment, a cognitive fitness test, to help them better understand their own brain.

The Brain That Changes Itself (6)

"I knew that the words 'mother' and 'daughter' meant but no the expression 'mother's daughter,'" Zazetsky wrote, "The expressions 'mother's daughter' and 'daughter's mother' sounded just the same to me. I also had trouble with expressions like 'Is an elephant bigger than a fly?' All I could figure out was that a fly was small and an elephant is big, but I didn't understand the words 'bigger' and 'smaller.'"

......

She isolated herself and began toiling to the point of exhaustion, week after week --- with only brief breaks for sleep --- at mental exercises she designed, though she had no guarantee they would lead anywhere.

有时候一个人有缺陷或是残疾，或者遇到巨大的困难，或是处于特别无助的境地，这些劣势会激发出人深藏的潜力，反倒创造出比健康人或身处顺境的人要好得多的成绩来。

The Brain That Changes Itself (5)

George knew nothing about rehabilitation, and his ignorance turned out to be a godsend, because he succeeded by breaking all its current rules, unencumbered by pessimistic theories.