來自Claremont Graduate Universtiy的Paul J.Zak教授在11月7日的《公共科學圖書館·綜合》（PLoS ONE）上發(fā)表了一篇題為“催產(chǎn)素讓人慷慨”（Oxytocin Increases Generosity in Humans）的研究論文,。該研究是在他們兩年前發(fā)表在《自然》雜志上的有關催產(chǎn)素和信任的新發(fā)現(xiàn)的延伸,。
在這項研究中，Zak和他的同事讓參與試驗者服用一定劑量的催產(chǎn)素和一種安慰劑，然后測試他們?nèi)绾闻c陌生者分錢,。結(jié)果基本上是一邊倒：那些接受了催產(chǎn)素的人給出的錢比那些接收安慰劑的人多出80%,。
Zak指出,，這意味著盡管我們天生是利他,、無私心的，我們還會在感覺對另外一個人產(chǎn)生移情作用時很大方,。就是這種“移情作用”使得我們打開錢包去大方地幫助陌生人,。這項試驗的結(jié)果證實了該研究組之前的研究發(fā)現(xiàn)：催產(chǎn)素影響信任，但是對慷慨程度的影響更加大,。
催產(chǎn)素尤其能夠影響人用錢時的慷慨程度,。在之前的研究中，Zak證實了催產(chǎn)素和信任之間的關聯(lián),，從而弄清了古老的荷爾蒙導致大腦中化學變化的一個遷移——這在進化上很重要,。因為我們越容易相信別人并合作，我們就越能夠一起獲益,。
垂體后葉組織中所提純的一種激素,。由下丘腦的室旁核合成，系神經(jīng)內(nèi)分泌,。合成后沿室旁核—垂體束的軸漿流動而至垂體后葉,，貯存于后葉的神經(jīng)末梢顆粒中,，為8個氨基酸組成的多肽。
催產(chǎn)素具有刺激乳腺及子宮的雙重作用：對乳腺有促進乳腺射乳的作用,，作用于乳腺內(nèi)平滑肌，使其收縮產(chǎn)生壓力,，從而使乳汁排出腺泡進入導管和乳竇,。吸吮時所產(chǎn)生的負壓克服乳頭括約肌阻力，使乳汁流出,。對非孕子宮作用小,，對妊娠子宮，在妊娠末期對其敏感,。雌激素可增加子宮對催產(chǎn)素的敏感性,，而孕激素作用則相反。由于催產(chǎn)素可使子宮強烈收縮,，可減少產(chǎn)后流血,。臨床上常用于產(chǎn)后止血。刺激催產(chǎn)素分泌的有效刺激為吸吮乳頭和擴張子宮頸,，為反射活動,，神經(jīng)沖動由外周神經(jīng)傳入中樞神經(jīng)系統(tǒng)，興奮下丘腦室旁核,，引起催產(chǎn)素釋放,。
此前，以色列科學家的一項最新研究發(fā)現(xiàn),，一種大腦垂體分泌催產(chǎn)素(Oxytocin)影響著人類中母子緊密關系的程度,。
原始出處:
PLoS ONE
Oxytocin Increases Generosity in Humans
Paul J. Zak1,2*, Angela A. Stanton3, Sheila Ahmadi4
1 Center for Neuroeconomics Studies and Department of Economics, Claremont Graduate University, Claremont, California, United States of America, 2 Department of Neurology, Loma Linda University Medical Center, Loma Linda, California, United States of America, 3 Argyros School of Business & Economics, Chapman University, Orange, California, United States of America, 4 Division of Endocrinology, Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
Abstract
Human beings routinely help strangers at costs to themselves. Sometimes the help offered is generous—offering more than the other expects. The proximate mechanisms supporting generosity are not well-understood, but several lines of research suggest a role for empathy. In this study, participants were infused with 40 IU oxytocin (OT) or placebo and engaged in a blinded, one-shot decision on how to split a sum of money with a stranger that could be rejected. Those on OT were 80% more generous than those given a placebo. OT had no effect on a unilateral monetary transfer task dissociating generosity from altruism. OT and altruism together predicted almost half the interpersonal variation in generosity. Notably, OT had twofold larger impact on generosity compared to altruism. This indicates that generosity is associated with both altruism as well as an emotional identification with another person.
Received: June 16, 2007; Accepted: October 13, 2007; Published: November 7, 2007
英文全文鏈接：
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0001128
