【雙語閱讀】心理幸福感.

　　Science and Technology Mental well-being A New York state of mind

　　Urban brains behave differently from rural ones

　　"HELL is a city much like London," opined Percy Bysshe Shelley in 1819. Modern academics agree. Last year Dutch researchers showed that city dwellers have a 21% higher risk of developing anxiety disorders than do their calmer rural countrymen, and a 39% higher risk of developing mood disorders. But exactly how the inner workings of the urban and rural minds cause this difference has remained obscure—until now. A study just published in Nature by Andreas Meyer-Lindenberg of the University of Heidelberg and his colleagues has used a scanning technique called functional magnetic-resonance imaging (fMRI) to examine the brains of city dwellers and country bumpkins when they are under stress.

　　In Dr Meyer-Lindenberg&aposs first experiment, participants lying with their heads in a scanner took maths tests that they were doomed to fail (the researchers had designed success rates to be just 25-40%). To make the experience still more humiliating, the team provided negative feedback through headphones, all the while checking participants for indications of stress, such as high blood pressure.

　　The urbanites&apos general mental health did not differ from that of their provincial counterparts. However, their brains dealt with the stress imposed by the experimenters in different ways. These differences were noticeable in two regions: the amygdalas and the perigenual anterior cingulate cortex (pACC). The amygdalas are a pair of structures, one in each cerebral hemisphere, that are found deep inside the brain and are responsible for assessing threats and generating the emotion of fear. The pACC is part of the cerebral cortex (again, found in both hemispheres) that regulates the amygdalas.

　　People living in the countryside had the lowest levels of activity in their amygdalas. Those living in towns had higher levels. City dwellers had the highest. Not that surprising, to those of a Shelleyesque disposition. In the case of the pACC, however, what mattered was not where someone was living now, but where he or she was brought up. The more urban a person&aposs childhood, the more active his pACC, regardless of where he was dwelling at the time of the experiment.

　　The amygdalas thus seem to respond to the here-and-now whereas the pACC is programmed early on, and does not react in the same, flexible way as the amygdalas. Second-to-second changes in its activity might, though, be expected to認(rèn)為 be correlated with changes in the amygdalas, because of its role in regulating them. fMRI allows such correlations to be measured.

　　In the cases of those brought up in the countryside, regardless of where they now live, the correlations were as expected. For those brought up in cities, however, these correlations broke down. The regulatory mechanism of the native urbanite, in other words, seems to be out of kilter. Further evidence, then, for Shelley&aposs point of view. Moreover, it is also known that the pACC-amygdala link is often out of kilter in schizophrenia, and that schizophrenia is more common among city dwellers than country folk. Dr Meyer-Lindenberg is carul not to claim that his results show the cause of this connection. But they might.

　　Dr Meyer-Lindenberg and his team conducted several subsequent experiments to check their findings. They asked participants to complete more maths tests—and also tests in which they mentally rotated an object—while investigators chided them about their performance. The results matched those of the first test. They also studied another group of volunteers, who were given stress-free tasks to complete. These experiments showed no activity in either the amygdalas or the pACC, suggesting that the earlier results were indeed the result of social stress rather than mental exertion.

　　As is usually the case in studies of this sort, the sample size was small (and therore not as robust as might be desirable) and the result showed an association, rather than a dinite, causal relationship. That association is, nevertheless, interesting. Living in cities brings many benits, but Dr Meyer-Lindenberg&aposs work suggests that Shelley and his fellow Romantics had at least half a point.

　　【中文對照翻譯】

　　科技 心理幸福感 都市心理

　　都市人和鄉(xiāng)村人大腦的不同活動

　　1819年，波比?雪萊曾說道："倫敦就像地獄。" 現(xiàn)在，現(xiàn)代學(xué)者們同意他的觀點(diǎn)。 去年，荷蘭研究員們表示倫敦城市居民患焦慮性障礙癥的風(fēng)險(xiǎn)比倫敦的寧靜鄉(xiāng)村里的居民的風(fēng)險(xiǎn)要高21%，而患上心境障礙的風(fēng)險(xiǎn)要比鄉(xiāng)村居民的風(fēng)險(xiǎn)高31%。 但是，直到現(xiàn)在，對于城市居民和鄉(xiāng)村居民各自的大腦活動是怎么引起患病的不同風(fēng)險(xiǎn)，人們還不太清楚。 在德國海登堡大學(xué)的Andreas Meyer-Lindenberg和他的同事們剛剛在Nature上發(fā)表的研究中，Andreas和他的同事們使用了一種叫做機(jī)能性磁共振成像(fMRI)的掃描技術(shù)來觀測城市居民和鄉(xiāng)村居民在承受心理壓力時的大腦活動。

　　在Meyer-Lindenberg博士的首次試驗(yàn)中，試驗(yàn)者們都躺著，他們的頭部都在一個掃描器中，同時做著他們必定做不來的數(shù)學(xué)題(研究者們把試題的通過率剛好設(shè)計(jì)在25%到40%)。 為了使試驗(yàn)變得更令人難堪，研究者們會通過對講機(jī)給試驗(yàn)者們傳達(dá)消極的反饋，試驗(yàn)首末研究者們檢測試驗(yàn)者們的心理壓力指標(biāo)，比如高血壓。

　　都市人的總體心理健康和鄉(xiāng)村人的沒有什么區(qū)別。 不過，都市人和鄉(xiāng)村人的大腦處理研究人員對他們施加的壓力的方式不同。 這些差異在杏仁核和前扣帶皮層(pacc)兩個區(qū)域較為明顯。 杏仁核是成對的，兩個大腦半球中各有一個，它們在大腦的深處，有辨識危險(xiǎn)和產(chǎn)生恐懼心理的作用。 前扣帶皮層是大腦皮層的一部分(也在兩個大腦半球的深處)，它們控制著杏仁核。

　　鄉(xiāng)村人的杏仁核顯示出最低的活躍水平。 城鎮(zhèn)人的杏仁核則顯示出較高的活躍水平。 而都市人的是最高的。 對于那些和雪萊的觀點(diǎn)一致的人來說，這一點(diǎn)也不奇怪。 然而，試驗(yàn)者們的前扣帶皮層的活動則跟他們在哪里長大有關(guān)，跟他們現(xiàn)在生活在那里無關(guān)。 童年時，一個人在城市里生活的越久，那么在實(shí)驗(yàn)中，他的前扣帶皮層會越活躍，前扣帶皮層的活躍水平與他在實(shí)驗(yàn)期間的住所無關(guān)。

　　因此，杏仁核看起來是對一個人生活現(xiàn)狀的反饋，然而，前扣帶皮層在一個人的幼年時期就開始記憶，它跟杏仁核的反饋不同，相比之下，杏仁核的活動跟靈活。 盡管人們認(rèn)為前扣帶皮層活動的每秒變化可能和杏仁核中的變化有關(guān)，因?yàn)樗锌刂菩尤屎说淖饔谩?機(jī)能性磁共振成像使得這種關(guān)聯(lián)可測。

　　實(shí)驗(yàn)中，不論試驗(yàn)者現(xiàn)在住在哪里，只要他們在鄉(xiāng)村長大，那么在他們的大腦中，前扣帶皮層和杏仁核之間的聯(lián)系是在預(yù)料之中的。 然而，對于那些在城市里長大的人，這些聯(lián)系中斷了。 換而言之，對于從小生活在城市里的人而言，他們的前扣帶皮層的調(diào)節(jié)機(jī)制似乎失常了。 那么，這是印證雪萊的觀點(diǎn)的又一個證據(jù)。 另外，人們都知道，在精神分裂癥患者的大腦中，前扣帶皮層和杏仁核的聯(lián)系常常會失常，并且，精神分裂癥在都市人群中比在鄉(xiāng)村人群中更常見。 Meyer-Lindenberg博士十分嚴(yán)謹(jǐn)，沒有公布他的實(shí)驗(yàn)結(jié)果，這些結(jié)果顯示了前扣帶皮層和杏仁核相聯(lián)系的原因。 但是事實(shí)可能就像實(shí)驗(yàn)結(jié)果那樣。

　　為了檢驗(yàn)他們的發(fā)現(xiàn)，Meyer-Lindenberg博士和他的研究團(tuán)隊(duì)連續(xù)進(jìn)行了幾次實(shí)驗(yàn)。 在實(shí)驗(yàn)中，他們要求試驗(yàn)者做更多的數(shù)學(xué)題(這些題還是會引起試驗(yàn)者們的心理起伏)，同時，研究者們還是會對試驗(yàn)者們的表現(xiàn)指指點(diǎn)點(diǎn)。 實(shí)驗(yàn)結(jié)果還是和第一次實(shí)驗(yàn)結(jié)果相吻合。 他們還對一組試驗(yàn)者進(jìn)行研究，在實(shí)驗(yàn)中，這些試驗(yàn)者需要完成一些簡單輕松的任務(wù)。 在這些實(shí)驗(yàn)中，試驗(yàn)者的大腦中既沒有顯示杏仁核的活動，也沒有顯示前扣帶皮層的活動，這表明之前的實(shí)驗(yàn)結(jié)果確實(shí)是由社會壓力引起的，而不是由心理活動引起的。

　　和這類研究的其他情形一樣，這次實(shí)驗(yàn)的樣本容量太小了(因此不足以令人信服)，并且研究結(jié)果只是種猜想，而不是一種肯定的、有根據(jù)的關(guān)系。 不過，這種猜想很有趣。 雖然生活在城市中能給人們帶來很多好處，但是Meyer-Lindenberg博士的研究表明，雪萊和其他浪漫主義者的觀點(diǎn)對了一半。

　　Science and Technology Mental well-being A New York state of mind

　　Urban brains behave differently from rural ones

　　"HELL is a city much like London," opined Percy Bysshe Shelley in 1819. Modern academics agree. Last year Dutch researchers showed that city dwellers have a 21% higher risk of developing anxiety disorders than do their calmer rural countrymen, and a 39% higher risk of developing mood disorders. But exactly how the inner workings of the urban and rural minds cause this difference has remained obscure—until now. A study just published in Nature by Andreas Meyer-Lindenberg of the University of Heidelberg and his colleagues has used a scanning technique called functional magnetic-resonance imaging (fMRI) to examine the brains of city dwellers and country bumpkins when they are under stress.

　　In Dr Meyer-Lindenberg&aposs first experiment, participants lying with their heads in a scanner took maths tests that they were doomed to fail (the researchers had designed success rates to be just 25-40%). To make the experience still more humiliating, the team provided negative feedback through headphones, all the while checking participants for indications of stress, such as high blood pressure.

　　The urbanites&apos general mental health did not differ from that of their provincial counterparts. However, their brains dealt with the stress imposed by the experimenters in different ways. These differences were noticeable in two regions: the amygdalas and the perigenual anterior cingulate cortex (pACC). The amygdalas are a pair of structures, one in each cerebral hemisphere, that are found deep inside the brain and are responsible for assessing threats and generating the emotion of fear. The pACC is part of the cerebral cortex (again, found in both hemispheres) that regulates the amygdalas.

　　People living in the countryside had the lowest levels of activity in their amygdalas. Those living in towns had higher levels. City dwellers had the highest. Not that surprising, to those of a Shelleyesque disposition. In the case of the pACC, however, what mattered was not where someone was living now, but where he or she was brought up. The more urban a person&aposs childhood, the more active his pACC, regardless of where he was dwelling at the time of the experiment.

　　The amygdalas thus seem to respond to the here-and-now whereas the pACC is programmed early on, and does not react in the same, flexible way as the amygdalas. Second-to-second changes in its activity might, though, be expected to認(rèn)為 be correlated with changes in the amygdalas, because of its role in regulating them. fMRI allows such correlations to be measured.

　　In the cases of those brought up in the countryside, regardless of where they now live, the correlations were as expected. For those brought up in cities, however, these correlations broke down. The regulatory mechanism of the native urbanite, in other words, seems to be out of kilter. Further evidence, then, for Shelley&aposs point of view. Moreover, it is also known that the pACC-amygdala link is often out of kilter in schizophrenia, and that schizophrenia is more common among city dwellers than country folk. Dr Meyer-Lindenberg is carul not to claim that his results show the cause of this connection. But they might.

　　Dr Meyer-Lindenberg and his team conducted several subsequent experiments to check their findings. They asked participants to complete more maths tests—and also tests in which they mentally rotated an object—while investigators chided them about their performance. The results matched those of the first test. They also studied another group of volunteers, who were given stress-free tasks to complete. These experiments showed no activity in either the amygdalas or the pACC, suggesting that the earlier results were indeed the result of social stress rather than mental exertion.

　　As is usually the case in studies of this sort, the sample size was small (and therore not as robust as might be desirable) and the result showed an association, rather than a dinite, causal relationship. That association is, nevertheless, interesting. Living in cities brings many benits, but Dr Meyer-Lindenberg&aposs work suggests that Shelley and his fellow Romantics had at least half a point.

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