62. Neuroscience and social deprivation

I am just a poor boy though my story's seldom told
Apr 2nd 2009 From The Economist print edition

How poverty passes from generation to generation is now becoming clearer. The answer lies in the effect of stress on two particular parts of the brain

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THAT the children of the poor underachieve in later life, and thus remain poor themselves, is one of the enduring problems of society. Sociologists have studied and described it. Socialists have tried to abolish it by dictatorship and central planning. Liberals have preferred democracy and opportunity. But nobody has truly understood what causes it. Until, perhaps, now.
The crucial breakthrough was made three years ago, when Martha Farah of the University of Pennsylvania showed that the working memories of children who have been raised in poverty have smaller capacities than those of middle-class children. Working memory is the ability to hold bits of information in the brain for current usethe digits of a phone number, for example. It is crucial for comprehending languages, for reading and for solving problems. Entry into the working memory is also a prerequisite for something to be learnt permanently as part of declarative memorythe stuff a person knows explicitly, like the dates of famous battles, rather than what he knows implicitly, like how to ride a bicycle.
Since Dr Farah's discovery, Gary Evans and Michelle Schamberg of Cornell University have studied the phenomenon in more detail. As they report in this week's Proceedings of the National Academy of Sciences, they have found that the reduced capacity of the memories of the poor is almost certainly the result of stress affecting the way that childish brains develop.
Dr Evans's and Dr Schamberg's volunteers were 195 participants in a long-term sociological and medical study that Dr Evans is carrying out in New York state. At the time, the participants were 17 years old. All are white, and the numbers of men and women are about equal.

A. 어휘
neuroscience 신경과학. deprivation 상실, 剝奪(박탈). effect 영향.
particular parts 특별한 부분. the poor 빈곤층, 가난한 사람들.
underachieve 지능지수이하의 성적을 따다. enduring 지속적인, 영속적인.
abolish 폐지하다. dictatorship 독재. central planning 중앙계획(공산주의국가의 정부통제 경제). liberal 자유주의자. prefer 선호하다. cause 원인이 되다.
crucial 결정적인. breakthrough 돌파구. working memories 활동적인 기억.
raise 양육하다. capacity 용량, 능력. current use 通用(통용). cf. current 電流(전류).
digit 아라비아 숫자. comprehend 이해하다, 파악하다. entry 들어가기.
prerequisite 필요한 조건. permanently 永久的(영구적)으로.
declarative memory 선언적 기억. explicitly 명백하게. implicit 함축적인, 맹목적인.
proceedings 학회의 회보, 의사록, 회의록. participant 참가자.

B. 구문
- the reduced capacity of the memories. . . childish brains develop.
[가난한 사람들의 축소된 기억능력은 분명히 어릴 때 뇌의 발달형태에 영향을 미치는 스트레스의 결과이다.]

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Stress in the city
To measure the amount of stress an individual had suffered over the course of his life, the two researchers used an index known as allostatic load. This is a combination of the values of six variables: diastolic and systolic blood pressurethe concentrations of three stress-related hormonesand the body-mass index, a measure of obesity. For all six, a higher value indicates a more stressful lifeand for all six, the values were higher, on average, in poor children than in those who were middle class. Moreover, because Dr Evans's wider study had followed the participants from birth, the two researchers were able to estimate what proportion of each child's life had been spent in poverty. That more precise figure, too, was correlated with the allostatic load.
The capacity of a 17-year-old's working memory was also correlated with allostatic load. Those who had spent their whole lives in poverty could hold an average of 8.5 items in their memory at any time. Those brought up in a middle-class family could manage 9.4, and those whose economic and social experiences had been mixed were in the middle.
These two correlations do not by themselves prove that chronic stress damages the memory, but Dr Evans and Dr Schamberg then applied a statistical technique called hierarchical regression to the results. They were able to use this to remove the effect of allostatic load on the relationship between poverty and memory discovered originally by Dr Farah. When they did so, that relationship disappeared. In other words, the diminution of memory in the poorer members of their study was entirely explained by stress, rather than by any more general aspect of poverty.

A. 어휘
measure 측정하다. index 指標(지표).
allostatic load 심리적 안정을 유지하는 데 필요한 생리학적 및 행동과학적 부담.
cf. allostasis→Allostasis is the process of achieving stability, or homeostasis, through physiological or behavioral change. Allostatic load refers to the cumulative cost to the body of allostasis.
over the course of his life 生(생)의 道程(도정)에서. combination 결합.
variable 變數(변수). diastolic 심장이완의. systolic 심장수축의.
blood pressure 혈압.
body-mass index(BMI) 過體重(과체중)여부의 판정기준이 되는 指數(지수).
obesity 비만. higher value 보다 높은 數値(수치). indicate 가리키다.
participants 참여자(조사대상자). proportion 비율. precise 정확한.
correlate 상호 관련되다. capacity 용량, 容積(용적). item 項目(항목).
correlation 상관관계. chronic 만성적인. apply...to ...에 적용하다.
statistical technique 통계적 技法(기법). hierarchical 계급제도의, 계층적인.
regression 퇴보, 退化(퇴화), 후퇴. remove 제거하다. effect 영향.
diminution 감소. aspect 樣相(양상).

B. 구문
- because Dr Evans's wider study. . . life had been spent in poverty.
[Dr Evans의 보다 광범위한 연구는 연구대상자들을 출생 때부터 추적하였기 때문에
아동들 각각의 생애 중에서 어느 정도의 비율이 빈곤 속에서 보내어 졌는가를 평가할 수 있었다.]