首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Scientists have long believed that constructing memories is like playing with neurological toys. Exposed to a barrage of sensati
Scientists have long believed that constructing memories is like playing with neurological toys. Exposed to a barrage of sensati
admin
2012-12-30
53
问题
Scientists have long believed that constructing memories is like playing with neurological toys. Exposed to a barrage of sensations from the outside world, we connect together brain cells to form new patterns of electrical connections that stand for images, smells, touches and sounds.
The most unshakable part of this belief is that the neurons used to build these memory circuits are depletable resource, like petroleum or gold. We are each given a finite number of cells, and the supply gets smaller each year. That is certainly how it feels as memories blur with middle age and it gets harder and harder to learn new things. Maybe it’s time for this notion to be forgotten-or at least radically revised.
In the past two years, a series of confusing experiments has forced scientific researchers to rethink this and other assumptions about how memory works. The perplexing results of these experiments remind scientists how much they have to learn about one of the last great mysteries-how the brain keeps a record of our individual passage through life, allowing us to carry the past inside our head.
This much seems clear: the traces of memory-or engrams as neuroscientists call them-are first forged deep inside the brain in an area called the hippocampus. This area stores the engrams temporarily until they are transferred somehow (perhaps during sleep) to permanent storage sites throughout the cerebral cortex. This area, located behind the forehead, is often described as the center of intelligence and perception. Here, as in the hippocampus, the information is thought to reside in the form of neurological scribbles, clusters of connected cells.
Until now our old view of brain functionality has been that these patterns ate constructed from the supply of neurons that have been in place since birth. New memories don’t require new neurons-just new ways of connecting the old ones together. Retrieving a memory is a matter of activating one of these circuits, coaxing the original stimulus back to life.
The picture appears very sensible. The billions of neurons in a single brain can be arranged in countless combinations, providing more than enough clusters to record even the richest life. If adult brains were cranking out new neurons as easily ad skin and bone from new cells, it would serve only to scramble memory’s delicate ornamental pattern.
Studies with adult monkeys in the mid-1960s seemed to support the belief that the supply of neurons is fixed at birth. Therefore the surprise when Elizabeth Gould and Charles Gross of Princeton University reported last year that the monkeys they studied seemed to be producing thousands of new neurons a day in the hippocampus of their brain. Even more surprising, Gould and Gross found evidence that a steady stream of the fresh cells may be continually moving to the cerebral cortex.
No one is quite sure what to make of these findings. There had already been hints that spawning of brain cells, a process called neurogenesis, occurs in animals with more primitive nervous systems. For years, Fernando Nottebohm of Rockefeller University has been showing that canaries create a new batch of neurons every time they learn a song, then slough them off when it’s time to change tunes.
But it was widely assumed that in mammals and especially primates this manufacture of new brain parts had long ago been phased out by evolution. With a greater need to store memories for a long time, these creatures would need to ensure that the engrams weren’t disrupted by interloping new cells.
Which of the following is true according to the old view of memory?
选项
A、The neurons used to build the memory are a depletable resource.
B、The reason of memory loss as one grows older is that the neurons are worn out with the increase of age.
C、New memories do not need the supply of new neurons in the brain.
D、All of above.
答案
D
解析
细节题。此题不难,基本出处在原文第二和第五段,The most unshakable part of this belief is that the neurons used to build these memory circuits are depletable resource…”.“That is certainly how it feels as memories blur with middle age and it gets harder and harder to learn new things.”,这就涵盖了AB两个选项,而C选项也是第五段的原话,“New memories don’t require new neurons…”,所以不难选出D为正确项。
转载请注明原文地址:https://www.kaotiyun.com/show/ukaO777K
0
专业英语八级
相关试题推荐
HowtoConquerPublicSpeakingFearⅠ.IntroductionA.Publicspeaking—acommonsourceofstressforeveryoneB.Thetru
Whentheendoftheworldcomes,we’llknowwhattoblame.ScientistshavefoundcompellingevidencethattheSunhasababybro
Thefamousline"Tobeornottobe"comesfrom______.
IntheUnitedStates,charterschoolsprovidealternativesto"regular"publicschools.Unlikemostpublicschools,chartersdon
TV,Internetandradioareverypopularnowadays.Somepeoplesaythattheywillreplacebooksandwrittenwordsasthemainsou
I.CausesofBreakdownsin(1)【1】______1.Onstudents’part—insufficientcommandoverthe(2)ofEnglish【2】______—p
WiththeexplosionofexcitementabouttheInternet,thereseemstobeanothertypeofaddictionthathasinvadedthehumanpsyc
Thespecializedortechnicallanguageofatrade,profession,orsimilargroupiscalled______.
CarrieMeeberappearsin______.
Culturereferstothesocialheritageofapeople—thelearnedpatternsforthinking,feelingandactingthatcharacterizea
随机试题
________,是指可以修复的废品在返修过程中所发生的修理费用。在废品的修复费用中,由造成废品的过失人负担的赔款,应从废品损失中扣除。
阵发性室上性心动过速最常发生于
下列哪项不是苓桂术甘汤中炙甘草的用意
不引起淤血的是
病人皮肤粗糙,呈猪皮样,皮下组织增厚,见于
某群山羊突然发病,高热达4l℃,呼吸困难。口鼻有脓性分泌物,口腔黏膜先红肿,后破溃,腹泻,拉带血水样稀便。病死率达50%。剖检见皱胃黏膜有糜烂病灶,结肠和直肠结合处有条纹状出血。引起该病的病原是()
下列选项中,说法不正确的是()。
“弟子不必不如师,师不必贤于弟子,闻道有先后,术业有专攻,如是而已。”这种观点给当今教育的启示是()。
推进文化发展,基础在继承,关键在创新。继承和创新,是一个民族文化生生不息的两个重要轮子。这句话包含了一个深刻的哲学道理。下列与这一观点蕴涵相同哲理的是()。
一学生在学校受同学欺负,回到家后,妈妈对他说:“他为什么打你?你告诉老师,让老师跟他讲不可以打架的道理。”爸爸则说:“谁敢打你,下回你也打他!”对于这类家长的表现,以下几种描述最贴切的是()
最新回复
(
0
)