《中英對照》Why the young learn more easily 年輕人為甚麼學習較容易

◎鄭寺音

"Old dogs" may really find it hard to learn new tricks, a study of how memories form has suggested.

「老狗」可能真的會發現難學新把戲，一份記憶如何形成的研究顯示。

University of Oxford scientists say that adults may find learning more difficult than children because their brains store memories differently.

牛津大學的科學家說，成年人可能發現，學習比孩子困難，因為他們的腦子以不同的方式儲存記憶。

The study, in the journal Neuron, looked at nerve cell activity in rats. Experts said younger brains may learn things more easily, but older brains may store information more efficiently.

這份在「神經元」期刊上的研究，觀察老鼠的神經細胞活動。專家說，較年輕的腦子學東西可能較容易，但較老的腦部，可能較有效率地儲存資訊。

Nerve cells communicate by sending signals though synapses, junctions between the cells. But some synapses are "silent". Silent synapses are more prevalent in young brains, and are called on when new memories are laid down.

神經細胞透過細胞接合點──「突觸」──傳送信號，藉此來溝通。但一些突觸是「沉默的」。沉默的突觸在年輕腦中較普遍，儲存新記憶時，會用上沉默的突觸。

In older brains, there were fewer silent synapses - which the researchers believe is because they have been used up.

較老的腦部沉默突觸較少，研究人員認為，這是因為它們已被用盡的關係。

This means older brains have to reuse the "un-silenced" synapses, boosting their power with increased amounts of neurotransmitters.

這意味著較老的腦須重新使用「不沉默的」突觸，以增量的神經傳導物提高它們的力量。

《新聞辭典》

call on（sth）︰使用。例句：She would have to call on all her strength if she was to survive the next few months.（如果她要下幾個星期能存活，必須使出全力。）

boost︰動詞，提高；增加。例句：The company boosted its sales this year.（這家公司今年提高了銷售額。）