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
考研
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals to
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals to
admin
2010-01-13
36
问题
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals too. In one experiment, for example, behavioral immunologist (免疫学家) Mark Laudenslager, at the University of Denver, gave mild electric shocks to 24 rats. Half the animals could switch off the current by turning a wheel in their enclosure, while the other half could not. The rats in the two groups were paired so that each time one rat turned the wheel it protected both itself and its helpless Partner from the shock. Laudenslager found that the immune response was depressed below normal in the helpless rats but not in those that could turn off the electricity. What he has demonstrated, he believes, is that lack of control over an event, not the experience itself, is what wakens the immune system.
Other researchers agree, Jay Weiss, a psychologist at Duke University School of Medicine, has shown that animals who are allowed to control unpleasant stimuli don’t develop sleep disturbances or changes in brain chemistry typical of stressed rats. But if the animals are conditioned to confront with situations they have no control over, they later behave passively even when faced with experiences they can control. Such findings reinforce psychologists’ suspicions that the experience or perception of helplessness is one of the most harmful factors in depression.
One of the most startling examples of how the mind can alter the immune response was discovered by chance. In 1975 psychologist Robert Ader at the University of Rochester School of Medicine conditioned (使形成条件反射) mice to avoid saccharin (糖精) by simultaneously feeding them the sweetener and injecting them with a drug that while suppressing their immune systems caused stomach upsets. Associating the saccharin with the stomach pains, the mice quickly learned to avoid the sweetener. In order to extinguish this dislike for the sweetener, Ader reexposed the animals to saccharin, this time without the drug, and was astonished to find that those mice that had received the highest amounts of sweetener during their earlier conditioning died. He could only speculate that he had so successfully conditioned the rats that saccharin alone now served to weaken their immune systems enough to kill them.
According to the passage, the experience of helplessness causes rats to ______ .
选项
A、turn off the electricity
B、try to control unpleasant stimuli
C、become abnormally suspicious
D、behave passively in controllable situations
答案
D
解析
由第二段可知,如果动物们时常面临他们不能控制的局面,后来,即使在他们能控制局面的实验中,他们的行为也很被动。
转载请注明原文地址:https://kaotiyun.com/show/Q4mi777K
0
在职申硕(同等学力)英语
相关试题推荐
Insomeways,theUnitedStateshasmadespectacularprogress.Firesnolongerdestroy18,000buildingsastheydidintheGreat
Insomeways,theUnitedStateshasmadespectacularprogress.Firesnolongerdestroy18,000buildingsastheydidintheGreat
Researchersbelieveoneway(tominimizing)(thedamage)istoget(better)at(predicting)theriskoffire.
Accordingtothepassage,thevolunteers______.TherearemoreolderpeoplewhowanttodoVSObecause______.Ⅰ.morepeoplet
Nothingissouncertainasthefashionmarketwhereonestyle______overanotherbeforebeingreplaced.
Thenewbookfocusesontheconceptthattoachieveandmaintaintotalhealth,peopleneedphysical,socialandemotionalwell-b
Man:Everybody’shelpingoutwiththedinner.Wouldyoumakethesalad?Woman:Anythingbutthat.Question:Whatdoesthewoman
A:Pleasedeposittwentymorecents.B:______.
Accordingtoasurvey,whichwasbasedontheresponsesofover188,000students,today’straditional-agecollegefreshmenare"
随机试题
关于窝沟封闭剂,下列说法正确的是
A.根B.根茎C.块茎D.根及根茎E.鳞茎川贝母的药用部位是
风心病二尖瓣狭窄心电图表现正确的是
案例2014年,G淀粉公司雇佣临时人员把仓库改造成第三生产车间。该车间为长80m、宽50m、高15m的框架砖混结构建筑,分成打包间和产品暂存间。打包间用7m高砖墙与暂存间分隔。打包间内有打包机8台、振动筛8台。振动筛安装在6m高的二层钢
简述地理环境、人口因素在社会发展中的作用。
A.It’sreallyfamilyfirstB.therealworkwillstartwhentheywalkoffthestageC.thenitwasjustapenaltyD.becauseI’
十进制整数95转换成二进制整数是
【B1】【B6】
Usingapublictelephonemaywellbeoneof【C1】______oflife,demandingpatience,determinationand【C2】______,togetheronoccas
Theoceancoversthreequartersoftheearth’ssurface,produces90percentofallitslife-supportingoxygen,andisthedrivin
最新回复
(
0
)