Jet Lag and the Brain

54 时差对大脑的影响

DATE=6-6-01
TITLE=SCIENCE REPORT- Jet Lag and the Brain
BYLINE=Nancy Steinbach

(Start at 59")This is Steve Ember with the VOA Special English Science Report.
A new study says one part of the human brain may become smaller as the result of a condition known as (1) jet lag.  Jet lag results from flying long distances in an airplane.  Jet lag interferes¹ with a person's normal times for sleeping and waking.  People with jet lag may feel extremely tired for several days.  They also may have problems thinking clearly and remembering.
Kwangwook Cho is a researcher at the University of Bristol in Britain.  He reported the findings of his jet lag study in the publication Nature (2) Neuroscience. 
The study involved twenty young women who worked for international airlines.  The women had served passengers on airplanes for five years.  These flight attendants flew across many countries and at least seven time zones. 
In the study, the flight attendants had different amounts of time to recover from jet lag.  Half the women spent five days or fewer in their home areas between long flights.  The other half spent more than fourteen days in their home areas.
Mister Cho took some fluid from the women's mouths to measure levels of a (3) hormone² that increases during stress. He tested them to see if they could remember where black spots appeared on a computer screen.  And he took pictures of their brains using (4) magnetic (5) resonance³ (6) imaging.  This is a way to measure the size of the brain's (7) temporal (8) lobes⁴. 
Mister Cho found that the women who had less time between flights had smaller right temporal lobes. This area of the brain deals with recognizing and remembering what is seen.  The same group performed worse and had slower reaction times on the visual memory test.  And their (9) saliva⁵ samples showed higher levels of stress hormones⁶.
Mister Cho says he believes the brain needs at least ten days to recover after a long trip.  He says airline workers told him their ability to remember got worse after working on planes for about four years. Other studies have shown that increased feelings of stress can cause a loss of cells in the part of the brain that controls memory. 
Scientists say more tests are needed to study the effects of jet lag on the brain.  They want to find out if too much jet lag could (10) permanently⁷ affect memory. 
This VOA Special English Science Report was written by Nancy Steinbach.
This is Steve Ember.

(1) jet lag n. 时差
(2) neuroscience [9njUErEU`sai[ns] n.神经系统科学( 指神经病学、 神经化学等)
(3) hormone [ `hR:mEUn] n.荷尔蒙, 激素
(4) magnetic [mAg`netik] adj.磁的, 有磁性的, 有吸引力的
(5) resonance [ `rezEn[ns] n.共鸣, 回声, 反响, 中介
(6) imaging [i`mAdViN] [计] 成像
(7) temporal [ `temp[r[l] adj.时间的, 当时的, 暂时的
(8) lobe [lEUb] n.圆形突出部（尤指耳垂）
(9) saliva [sE`laiv[] n.口水, 唾液
(10) permanently [ `p[:mEnEntli] adv.永存地, 不变地

1 interferes   

vi. 妨碍，冲突，干涉

参考例句：

• The noise interferes with my work. 这噪音妨碍我的工作。
• That interferes with my plan. 那干扰了我的计划。

2 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

3 resonance   

n.洪亮；共鸣；共振

参考例句：

• Playing the piano sets up resonance in those glass ornaments.一弹钢琴那些玻璃饰物就会产生共振。
• The areas under the two resonance envelopes are unequal.两个共振峰下面的面积是不相等的。

4 lobes   

n.耳垂( lobe的名词复数 )；（器官的）叶；肺叶；脑叶

参考例句：

• The rotor has recesses in its three faces between the lobes. 转子在其凸角之间的三个面上有凹槽。 来自辞典例句
• The chalazal parts of the endosperm containing free nuclei forms several lobes. 包含游离核的合点端胚乳部分形成几个裂片。 来自辞典例句

5 saliva   

n.唾液，口水

参考例句：

• He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
• Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。

6 hormones   

n. 荷尔蒙，激素 名词hormone的复数形式

参考例句：

• This hormone interacts closely with other hormones in the body. 这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
• The adrenals produce a large per cent of a man's sex hormones. 肾上腺分泌人体的大部分性激素。

7 permanently   

adv.永恒地，永久地，固定不变地

参考例句：

• The accident left him permanently scarred.那次事故给他留下了永久的伤疤。
• The ship is now permanently moored on the Thames in London.该船现在永久地停泊在伦敦泰晤士河边。