“姜是老的辣”有了科學(xué)依據(jù)

Older Really Can Mean Wiser

“姜是老的辣”有了科學(xué)依據(jù)

Behind all those canned compliments for older adults — spry! wily! wise! — is an appreciation for something that scientists have had a hard time characterizing: mental faculties that improve with age.

年長(zhǎng)者通常會(huì)受到這樣的褒揚(yáng)：思維敏捷!老謀深算!睿智!在這些稱(chēng)贊的背后，是對(duì)某種東西的欣賞，科學(xué)家們一直很難描述的東西：隨著年齡增長(zhǎng)而增強(qiáng)的心智能力。

Knowledge is a large part of the equation, of course. People who are middle-aged and older tend to know more than young adults, by virtue of having been around longer, and score higher on vocabulary tests, crossword puzzles and other measures of so-called crystallized intelligence.

當(dāng)然，在這個(gè)等式中，知識(shí)占了很大一部分。與年輕人相比，中老年人知道的東西往往更多，因?yàn)樗麄兓钸^(guò)的年頭更長(zhǎng)，而且在詞匯測(cè)試、填字游戲和其他“晶態(tài)智力”測(cè)試中，中老年人的得分也比較高。

Still, young adults who consult their elders (mostly when desperate) don’t do so just to gather facts, solve crosswords or borrow a credit card. Nor, generally, are they looking for help with short-term memory or puzzle solving. Those abilities, called fluid intelligence, peak in the 20s.

不過(guò)，年輕人(主要是在絕望的時(shí)候)請(qǐng)教年長(zhǎng)者，不只是為了搜集事實(shí)、做填字游戲，或者借用信用卡。通常也不是為了解決短期記憶或解謎方面的問(wèn)題。這些能力稱(chēng)為“液態(tài)智力”，在20多歲時(shí)達(dá)到峰值。

No, the older brain offers something more, according to a new paper in the journal Psychological Science. Elements of social judgment and short-term memory, important pieces of the cognitive puzzle, may peak later in life than previously thought.

不，《心理科學(xué)》(Psychological Science)雜志上的新論文表示，年長(zhǎng)者的大腦可以提供更多的好處。社會(huì)判斷和短期記憶的一些元素是認(rèn)知能力的重要組成部分，它們達(dá)到峰值的時(shí)間可能比人們之前認(rèn)為的更晚一些。

The postdoctoral fellows Joshua Hartshorne of M.I.T. and Laura Germine of Harvard and Massachusetts General Hospital analyzed a huge trove of scores on cognitive tests taken by people of all ages. The researchers found that the broad split in age-related cognition — fluid in the young, crystallized in the old — masked several important nuances.

麻省理工(MIT)博士后約書(shū)亞·哈茨霍恩(Joshua Hartshorne)以及哈佛(Harvard)和馬薩諸塞州總醫(yī)院(Massachusetts General Hospital)博士后勞拉·杰米恩(Laura Germine)分析了大量由所有年齡段參加的認(rèn)知測(cè)試數(shù)據(jù)，發(fā)現(xiàn)在涉及年齡的認(rèn)知上，籠統(tǒng)的兩分法——年輕人液態(tài)智力高，年長(zhǎng)者晶態(tài)智力高——掩蓋了一些重要的細(xì)微差別。

“This dichotomy between early peaks and later peaks is way too coarse,” Dr. Hartshorne said. “There are a lot more patterns going on, and we need to take those into account to fully understand the effects of age on cognition.”

“早期達(dá)到高峰和較晚時(shí)候達(dá)到高峰，這種兩分法太粗略了，”哈茨霍恩博士說(shuō)。“此外還存在很多的模式，我們需要考慮這些因素，來(lái)充分了解年齡對(duì)認(rèn)知的影響。”

The new paper is hardly the first challenge to the scientific literature on age-related decline, and it won’t be the last. A year ago, German scientists argued that cognitive “deficits” in aging were caused largely by the accumulation of knowledge — that is, the brain slows down because it has to search a larger mental library of facts. That idea has stirred some debate among scientists.

諸多科學(xué)文獻(xiàn)談到了和年齡有關(guān)的認(rèn)知能力下降，這篇新論文既不是對(duì)相關(guān)結(jié)論的第一個(gè)挑戰(zhàn)，也不會(huì)是最后一個(gè)。一年前，德國(guó)科學(xué)家聲稱(chēng)，年齡增長(zhǎng)的認(rèn)知“缺陷”在很大程度上是由知識(shí)的積累造成的——也就是說(shuō)，大腦速度減慢，是因?yàn)樗枰谝粋€(gè)更大的腦部信息庫(kù)里搜索東西。這個(gè)說(shuō)法已經(jīng)在科學(xué)界引起了一些爭(zhēng)論。

Experts said the new analysis raised a different question: Are there distinct, independent elements of memory and cognition that peak at varying times of life?

一些專(zhuān)家稱(chēng)，這份新的分析結(jié)果提出了一個(gè)不同的問(wèn)題：在記憶力和認(rèn)知能力中，有沒(méi)有一些與眾不同的獨(dú)立的元素，是在生命中的不同時(shí)刻達(dá)到峰值的?

“I think they have more work to do to demonstrate that that’s the case,” said Denise Park, a professor of behavior and brain science at the University of Texas at Dallas. “But this is a provocative paper, and it’s going to have an impact on the field.”

“我認(rèn)為要證明這一點(diǎn)，他們還需要做更多工作，”德克薩斯州大學(xué)達(dá)拉斯分校(University of Texas at Dallas)行為與腦科學(xué)教授丹尼斯·帕克(Denise Park)說(shuō)。“但這篇論文已經(jīng)引發(fā)了討論，它將對(duì)這一領(lǐng)域產(chǎn)生影響。”

The strength of the new analysis is partly in its data. The study evaluated historic scores from the popular Wechsler intelligence test, and compared them with more recent results from tens of thousands of people who took short cognitive tests on the authors’ websites, testmybrain.org and gameswithwords.org. The one drawback of this approach is that, because it didn’t follow the same people over a lifetime, it might have missed the effect of different cultural experiences, said K. Warner Schaie, a researcher at Penn State University.

這個(gè)最新分析結(jié)果的強(qiáng)大之處，一定程度上在于它所采用的數(shù)據(jù)。這份研究評(píng)估了著名的韋氏智力測(cè)驗(yàn)(Wechsler intelligence test)的歷史得分?jǐn)?shù)據(jù)，將它們與數(shù)萬(wàn)人更近期的測(cè)試結(jié)果進(jìn)行了比較。這些參與者在作者的網(wǎng)站上進(jìn)行了簡(jiǎn)短的認(rèn)知測(cè)試，網(wǎng)址分別是 testmybrain.org和gameswithwords.org。賓夕法尼亞州立大學(xué)(Penn State)的研究人員K·瓦爾納·沙依(K. Warner Schaie)說(shuō)，這種方法的缺陷在于，由于它不是追蹤同一批人在人生各個(gè)階段的情況，因此可能忽視了不同文化經(jīng)歷產(chǎn)生的影響。

But most previous studies have not been nearly as large, or had such a range of ages. Participants on the websites were 10 to 89 years old, and they took a large battery of tests, measuring skills like memory for abstract symbols and strings of digits, problem solving, and facility reading emotions from strangers’ eyes.

然而，以往的多數(shù)研究都沒(méi)有達(dá)到如此大的規(guī)模，也沒(méi)有覆蓋這么廣的年齡段。網(wǎng)站上的參與者年齡在10歲到89歲之間，他們參與了大量的測(cè)試，評(píng)估了對(duì)抽象符號(hào)和數(shù)字串的記憶力、解決問(wèn)題的能力，以及根據(jù)眼神解讀陌生人情緒的能力。

At least as important, the researchers looked at the effect of age on each type of test. Previous research had often grouped related tests together, on the assumption that they captured a single underlying attribute in the same way a coach might rate, say, athleticism based on a person’s speed, strength and vertical leaping ability.

同樣重要的是，研究人員觀察了年齡對(duì)每一項(xiàng)測(cè)試的影響。以往的研究經(jīng)常把相關(guān)的測(cè)試分為一組，想當(dāng)然地認(rèn)為它們捕捉到了一項(xiàng)基本屬性，就像教練可以根據(jù)一個(gè)人的速度、力量和彈跳能力評(píng)估他的運(yùn)動(dòng)能力一樣。

The result of the new approach? “We found different abilities really maturing or ripening at different ages,” Dr. Germine said. “It’s a much richer picture of the life span than just calling it aging.”

這種新方法的結(jié)果如何?“我們發(fā)現(xiàn)不同的能力的確會(huì)在不同的年齡臻于成熟，”杰米恩說(shuō)。“它反映了人生中豐富得多的變化，而不只是衰老。”

Processing speed — the quickness with which someone can manipulate digits, words or images, as if on a mental sketch board — generally peaks in the late teens, Dr. Germine and Dr. Hartshorne confirmed, and memory for some things, like names, does so in the early 20s. But the capacity of that sketch board, called working memory, peaks at least a decade later and is slow to decline. In particular, the ability to recall faces and do some mental manipulation of numbers peaked about age 30, the study found, “a fact difficult to assimilate into the fluid/crystalized intelligence dichotomy.”

杰米恩博士和哈茨霍恩博士證實(shí)，信息處理速度——如同頭腦中有一塊素描板，一個(gè)人在上面處理數(shù)字、單詞或圖像的速度——基本上在十八九歲的時(shí)候達(dá)到峰值;對(duì)一些事情的記憶力，比如對(duì)一些名字的記憶，會(huì)在20歲出頭的時(shí)候達(dá)到頂峰。但這個(gè)素描板的容量，即工作記憶，至少還要10年之后才能達(dá)到峰值，而且下降的速度很慢。特別值得一提的是，研究發(fā)現(xiàn)，記憶一些人的長(zhǎng)相以及心算的能力，會(huì)在30歲左右達(dá)到峰值，“這個(gè)事實(shí)很難用液態(tài)/晶態(tài)的智力二分法來(lái)解釋。”

The researchers also analyzed results from the Reading the Mind in the Eyes test. The test involves looking at snapshots of strangers’ eyes on a computer screen and determining their moods from a menu of options like “tentative,” “uncertain” and “skeptical.”

研究人員還分析了“眼神讀心能力測(cè)試”的結(jié)果。在這項(xiàng)測(cè)試中，測(cè)試者需要看著計(jì)算機(jī)屏幕上陌生人眼睛的照片，從一些選項(xiàng)中選出他們的心情，比如“猶豫”、“不確定”和“懷疑”。

“It’s not an easy test, and you’re not sure afterward how well you did,” Dr. Germine said. “I thought I’d done poorly but in fact did pretty well.” Yet people in their 40s or 50s consistently did the best, the study found, and the skill declined very slowly later in life.

“這個(gè)測(cè)試并不容易，你做完之后心里沒(méi)底，”杰米恩說(shuō)。“我以為我做的很糟糕，但實(shí)際上成績(jī)相當(dāng)不錯(cuò)。”然而研究發(fā)現(xiàn)，四五十歲的人成績(jī)最好，而且隨著年齡的進(jìn)一步增長(zhǎng)，這種能力下降得十分緩慢。

The picture that emerges from these findings is of an older brain that moves more slowly than its younger self, but is just as accurate in many areas and more adept at reading others’ moods — on top of being more knowledgeable. That’s a handy combination, given that so many important decisions people make intimately affects others.

這些發(fā)現(xiàn)所反映的情況是，年長(zhǎng)者的大腦的運(yùn)轉(zhuǎn)速度比年輕時(shí)慢，但在許多領(lǐng)域同樣敏銳，而且更擅長(zhǎng)察覺(jué)他人的情緒——不光是知識(shí)更淵博了?？紤]到人們做出的許多重要決定都會(huì)密切地影響他人，這是一個(gè)不錯(cuò)的狀態(tài)。

No one needs a cognitive scientist to explain that it’s better to approach a boss about a raise when he or she is in a good mood. But the older mind may be better able to head off interpersonal misjudgments and to navigate tricky situations.

沒(méi)人需要一名認(rèn)知科學(xué)家來(lái)告訴自己，為什么在老板心情好的時(shí)候，更適合找他談漲薪。但年長(zhǎng)一些的人可能更加擅長(zhǎng)避免人際關(guān)系上的誤判，以及應(yīng)付棘手的局面。

“As in, ‘that person’s not happy with all your quick thinking and young person’s processing speed — he’s about to punch you,’” said Zach Hambrick, a psychology professor at Michigan State University.

“比如，‘那個(gè)人看不慣你思維太快，那種年輕人的信息處理速度——他就要給你一拳了，’”密歇根大學(xué)的心理學(xué)教授扎克·漢布里克(Zach Hambrick)說(shuō)。

The details of this more textured picture of the aging brain are still far from clear, and social measures like the Reading the Mind in the Eyes test have not been used much in this kind of research, Dr. Hambrick and other experts said. And it is not apparent from the new analysis whether changes in cognition with age result from a single cause — like a decline in the speed of neural transmission — or to multiple ones.

漢布里克和其他專(zhuān)家說(shuō)，大腦衰老過(guò)程中更復(fù)雜情況的細(xì)節(jié)還很不清楚，眼神讀心能力等社會(huì)化衡量標(biāo)準(zhǔn)也沒(méi)有被大量用于此類(lèi)研究。此外，最新的分析結(jié)果也沒(méi)有告訴我們，認(rèn)知能力隨年齡增長(zhǎng)而發(fā)生的改變是單一因素——比如神經(jīng)傳輸速度的下降——還是多種原因造成的。