Altruism(1), one of the most difficult human behaviors to define, can be detected in brain scans, U.S. researchers reported on Sunday.

They found activity in a specific area of the brain could predict altruistic behavior -- and people's own reports of how selfish or giving they are.

"Although understanding the function of this brain region may not necessarily(2) identify what drives people like Mother Theresa, it may give clues(3) to the origins of important social behaviors like altruism," said Scott Huettel, a neuroscientist(4) at Duke University who led the study.

They set up an experiment in which they put 45 college students into a functional magnetic(5) resonance(6) imaging scanner, which can take real-time images of brain activity.

They gave the students various games to play, and told them that winning earned cash for either themselves or for a charity. The students had chosen the charities beforehand(7) from a list, the researchers report.

The students reacted differently depending on whether they won for themselves or for charity with the ones who described themselves as altruistic responding more strongly.

"The game involved reacting as fast as one can to the appearance of a target; if one responds fast enough, then money was earned," Huettel said.

The task was fairly simple, and the students did not give up any payments to themselves to give to the charities. But it cost enough effort that Huettel believes it did represent altruistic intent.

"Conversely, trying to watch people in their daily lives would make data collection nearly impossible. So, we settled on(8) self-reports as a good, albeit(9) imperfect, measure."

Huettel believes it is valid(10) to try to assess altruism scientifically.

"It is hardly the case that all altruistic acts come from people who are religiously faithful; there are undoubtedly many altruistic atheists(11)," He said.

"And, a religious explanation would have considerable(12) difficulty explaining why some animals help others of their species at significant cost or danger to themselves."

Next his team hopes to test children, and find out how and when altruism develops.

周日，美國(guó)研究人員稱，最難解釋的人類行為之一—利他主義可以通過(guò)腦部掃描探測(cè)。

他們發(fā)現(xiàn)腦部一塊特殊區(qū)域的活動(dòng)能預(yù)示利他主義行為—身體自己匯報(bào)自私度或者利他度。

本研究組長(zhǎng)、杜克大學(xué)神經(jīng)學(xué)家Scott Huettel說(shuō)：“盡管對(duì)這部分腦功能的認(rèn)識(shí)還無(wú)法解釋到底是什么可以讓人們像德蘭修女一樣，但卻能讓我們更加靠近諸如利他主義這樣的重要社會(huì)行為的根源。”

研究人員將45位大學(xué)生送入能夠?qū)崟r(shí)記錄腦部活動(dòng)的功能磁共振成像掃描儀。

他們讓學(xué)生們玩不同的游戲，并每次讓他們選擇贏的錢是留給自己還是捐獻(xiàn)福利機(jī)構(gòu)。游戲開(kāi)始前學(xué)生們可以從列表上選擇受捐贈(zèng)的福利機(jī)構(gòu)。

選擇不同受益者，游戲結(jié)果大大不同，同時(shí)自稱是利他主義者的學(xué)生的反應(yīng)更為強(qiáng)烈。

Huettel說(shuō)：“其中一個(gè)游戲是讓學(xué)生目擊突然出現(xiàn)的目標(biāo)，如果反應(yīng)夠快就能贏錢。”

任務(wù)都很簡(jiǎn)單，學(xué)生們?cè)诖诉^(guò)程中不會(huì)有任何金錢損失。但是Huettel認(rèn)為學(xué)生付出的努力足可以代表他們的利他意圖。

“相反地，通過(guò)觀察人們的日常生活搜集數(shù)據(jù)幾乎是不可能的。所以，我們認(rèn)為自我匯報(bào)是一種雖然不完美，但還不錯(cuò)的方法。”

Huettel認(rèn)為這是評(píng)估利他主義的科學(xué)有效途徑。

他說(shuō)：“并非所有的利他行為都來(lái)自有宗教信仰的人；毫無(wú)疑問(wèn)太多無(wú)神論者同樣是利他主義者。”

“而且，宗教無(wú)法解釋為什么有些動(dòng)物會(huì)付出很大代價(jià)、冒很大風(fēng)險(xiǎn)幫助同類。”

下一步，他的團(tuán)隊(duì)希望測(cè)試兒童，試圖發(fā)現(xiàn)利他主義行為是從何時(shí)、如何發(fā)展的。