To learn more about how exercise affects the brain, scientists in Ireland recently asked a group of sedentary male college students to take part in a memory test followed by strenuous exercise.
为了更好地了解运动是如何影响大脑的，爱尔兰的科学家们最近进行了一项实验。他们让一组平常不太运动的男大学生先进行剧烈运动，然后再给他们进行记忆力测试。
First, the young men watched a rapid-fire lineup of photos with the faces and names of strangers. After a break, they tried to recall the names they had just seen as the photos again zipped across a computer screen.
首先，这帮年轻人先快速的浏览一些照片，照片上都是陌生人的脸和名字。短暂休息之后，电脑屏幕上再迅速闪过这些照片，而他们则试着回忆照片上人的名字。
Afterward, half of the students rode a stationary bicycle, at an increasingly strenuous pace, until they were exhausted. The others sat quietly for 30 minutes. Then both groups took the brain-teaser test again.
之后，科学家让一半学生去骑固定式自行车，速度越骑越快，直到他们精疲力竭。另外一半学生则静静地坐30分钟。接着再让两组学生参加考验大脑的测试。
Notably, the exercised volunteers performed significantly better on the memory test than they had on their first try, while the volunteers who had rested did not improve.
明显地运动这组表现要比他们第一次参与的记忆测试成绩要好得多，然而在休息的那组记忆力没有变化。
Meanwhile, blood samples taken throughout the experiment offered a biological explanation for the boost in memory among the exercisers. Immediately after the strenuous activity, the cyclists had significantly higher levels of a protein known as brain-derived neurotrophic factor, or BDNF, which is known to promote the health of nerve cells. The men who had sat quietly showed no comparable change in BDNF levels.
与此同时，从试验者身上采血样从生物学的角度解释了参与运动的人的记忆力增强了。在激烈的运动之后，骑自行车的这组人记忆力立即明显提高，骑自行车的学生血液中一种叫做脑神经营养因子（或BDNF）的蛋白质浓度极高，促进了神经细胞的健康状态。静坐的这组人在脑源性神经营养因子水平上没有变化。
For some time, scientists have believed that BDNF helps explain why mental functioning appears to improve with exercise. However, they haven’t fully understood which parts of the brain are affected or how those effects influence thinking. The Irish study suggests that the increases in BDNF prompted by exercise may play a particular role in improving memory and recall.
科学家们一度认为脑源性神经营养因子有助于解释为什么运动可改进脑力功能。然而，他们并没有完全搞懂到底是大脑的哪个部分受到了影响或者这些效应是如何影响思考的。然而他们没有完全明白大脑受影响的部分或那些作用是如何影响思考的。爱尔兰研究建议脑源性神经营养因子可通过运动增加从而得到促进，可以在改进记忆力和回忆力方面起到特别的意义。
Other new studies have reached similar conclusions, among both people and animals, young and old. In one interesting experiment published last month, Brazilian scientists found that after sedentary elderly rats ran for a mere five minutes or so several days a week for five weeks, a cascade of biochemical processes ignited in the memory center of their brains, culminating in increased production of BDNF molecules there. The old, exercised animals then performed almost as well as much younger rats on rodent memory tests.
在人和动物之间，且不分老幼。已得出其它类似新研究结论。在上个月出版的一次有趣的试验中，让衰老且不活动的老鼠一周中有几天跑五分钟，坚持五周，结果发现它们大脑的记忆中心中产生了生物化学反应，产生了大量的BDNF分子。这些衰老，运动的老鼠在啮齿动物类记忆测试中的表现与比它们年轻许多的老鼠的表现一样好。
Another animal study, this one performed by researchers in the Brain Injury Research Center at the University of California, Los Angeles, and published in September in the journal Neuroscience, showed that if adult rats were allowed to run at will for a week, the memory center of their brains afterward contained more BDNF molecules than in sedentary rats, and teemed with a new population of precursor molecules that presumably would soon develop into fully functioning BDNF molecules.
另一项动物研究是由研究人员在洛杉矶加利福尼亚大学的大脑受伤研究中心执行的研究，并且研究报告出版在九月份的神经学杂志上，表明如果成年白鼠允许随意跑动一周的时间之后，他们的大脑记忆中心就比不怎么运动的白鼠含更多的脑源性神经营养因子（BDNF），并且全是新生的分子数量，假设会很快全部发展成脑源性神经营养因子。
Perhaps the most inspiring of the recent experiments is one involving aging human pilots. For the experiment, published last month in the journal Translational Psychiatry, scientists at Stanford University School of Medicine asked 144 experienced pilots ages 40 to 65 to operate a cockpit simulator three separate times over the course of two years.
或许最近的试验中最激励人的一次试验就是就一位上了年纪的飞行员进行测试。对于该项试验出版在上个月的精神医学翻译版本杂志上，斯坦福大学医学院的科学家们让144名40岁至65岁的试验飞行员在两年的时间里分三次操作驾驶舱模拟器。
For all of the pilots, performance declined somewhat as the years passed. A similar decline with age is common in all of us.
对于所有的飞行员来说，他们的记忆力随着年龄的增长都在一定程度上下降了。随着年龄的增长我们的记忆力普遍都出现类似程度的下降。
Many people find it more difficult to perform skilled tasks — driving an automobile, for instance – as they grow older, says Dr. Ahmad Salehi, an associate professor of psychiatry and behavioral sciences at Stanford and lead author of the study.
在斯坦福的一项有关精神医学教授、行为科学家、主要作家的该项研究中，艾哈迈德·萨利希博士说，随着他们年龄的增长—发现许多人执行技术任务能力更加困难—例如，开车。
But in this case, the decline was especially striking among one particular group of men. These aging pilots carried a common genetic variation that is believed to reduce BDNF activity in their brains. The men with a genetic tendency toward lower BDNF levels seemed to lose their ability to perform complicated tasks at almost double the rate of the men without the variation.
但是在这个情况下，尤其是在一组特殊的男性小组中，他们记忆力下降尤为明显。这些上了年纪的飞行员普遍进行了一次基因变异，认为可降低他们大脑中活动的脑源性神经营养因子（BDNF）。这个脑源性神经营养因子（BDNF）偏低含量的基因，看起来却丧失了执行复杂任务的能力，男性概率最多可成倍却没有变动。
While the pilot experiment wasn’t an exercise study, it does raise the question of whether strenuous exercise could slow such declines by raising BDNF levels, thereby salvaging our ability to perform skilled manual tasks well past middle age.
然而飞行试验却不属于运动研究，这就提出了问题是否激烈运动可通过增加脑源性神经营养因子（BDNF）含量的方式记忆力下降就慢，因此年过中年的人可很熟练地通过手工技术能力测试。
“So many studies have shown that exercise increases levels of BDNF, ” says Dr. Salehi. While he notes that other growth factors and body chemicals are “upregulated” by exercise, he believes BDNF holds the most promise.
“多项研究都表明运动可增加提高脑源性神经营养因子（BDNF）水平，”沙列西博士说。同时他注意到其它增长因素和身体化学物质通过运动是“上调的”，他认为脑源性神经营养因子（BDNF）最有前景。
“The one factor that shows the fastest, most consistent and greatest response is BDNF, ” he says. “It seems to be key to maintaining not just memory but skilled task performance.”
“这一因素表明脑源性神经营养因子最快、最具一致性并且反应最大，”他说。“看起来好像最关键的是进行维持而不只是技术任务方面的记忆力。”
Dr. Salehi plans next to examine the exercise histories of the pilots, to see whether those with the gene variant, which is common among people of European or Asian backgrounds, respond differently to workouts.
沙列西博士计划接下来检查这些飞行员的运动历史记录，来看一下是否那些基因发生了变化，欧洲或亚洲不同生活背景的人们对于运动普遍反映出不同结果。
In people who have the variant and less BDNF activity, “exercise is probably even more important, ” he says. “But for everyone, the evidence is very, very strong that physical activity will increase BDNF levels and improve cognitive health.”
对于脑源性神经营养因子（BDNF）活动较少的人们来说，“运动很可能更加重要，”他说。“但是对于每个人来说，证据非常非常充分且有说服力，身体运动会增加脑源性神经营养因子（BDNF）含量并改进认知方面的健康。”
|
