"Long before it's in the papers"
October 31, 2013


Love your enemy? Hormone spray may help with that, too

Oct. 31, 2013
Special to World Science  

Could in­hal­ing some­thing really help fos­ter world peace, as some hip­pies claim?

Don’t count on it. Yet a study has found that sniff­ing one spe­cial sub­stance may make peo­ple feel more sor­ry for the suf­fer­ing of out­siders, stig­ma­tized peo­ple and out­right en­e­mies. That chem­i­cal is ox­y­to­cin, a hor­mone al­ready nat­u­rally pre­s­ent in the brain and some­times called the trust hor­mone.

The study found that even peo­ple in­volved in one of the world’s most emo­tion­ally fraught con­flicts, the Is­rae­li-Pal­es­tin­ian strug­gle, seem to find a new heart for the oth­er side af­ter they in­hale ox­y­to­cin.

But the find­ings al­so run count­er to those of past stud­ies in some ways, sug­gest­ing that bi­ol­o­gists are only be­gin­ning to clar­i­fy the func­tion of the fas­ci­nat­ing hor­mone known to play a role in so­cial be­hav­ior and bond­ing in both hu­mans and an­i­mals.

“Oxy­tocin re­markably in­creased em­pa­thy to the pain of Pales­tini­ans” among Jew­ish Is­raelis in an ex­pe­ri­ment, wrote re­search­ers, re­port­ing their find­ings Sept. 22 on­line in the jour­nal Psy­cho­neu­ro­en­docrin­ol­ogy. The in­creased em­pa­thy re­duced the par­ti­ci­pants’ “in-group bi­as,” they added—the pre­dom­i­nant ten­den­cy of peo­ple to show more em­pa­thy for “those who they per­ceive as si­m­i­lar to them­selves.”

In their re­port, the re­search­ers said they re­cruited 55 Jew­ish Is­raelis. These par­ti­ci­pants were shown some pho­tos of peo­ple in pain­ful situa­t­ions, such as hav­ing a car hood closed on a hand, and oth­er pho­tos of peo­ple in non-pain­ful situa­t­ions. La­bels with the pho­tos in­di­cat­ed that the pic­tured per­son was from one of three groups. Ei­ther he or she was anoth­er Is­rae­li Jew; or an Arab—often viewed as the “en­e­my” group for Is­raelis; or a Eu­ro­pe­an, cho­sen as a middle-ground group.

The par­ti­ci­pants viewed the pho­tos af­ter hav­ing tak­en ei­ther ox­y­to­cin or an in­ac­tive sub­stance, and were lat­er as­sessed for how much em­pa­thy they showed to the peo­ple pic­tured. 

Ox­y­to­cin sig­nif­i­cantly in­creased par­ti­ci­pants’ em­pa­thy for the Arabs in pain, while leav­ing un­changed their em­pa­thy for the oth­er two groups in pain, the re­search­ers found. That sug­gests, they added, that ox­y­to­cin does­n’t nec­es­sarily make peo­ple em­pa­thize more with those they al­ready em­pa­thize with.

The ex­pe­ri­menters meas­ured view­ers’ em­pa­thy by ask­ing them to rate how much pain they thought the pic­tured per­son was ex­periencing.

Past stud­ies in­di­cate that tak­ing ox­y­to­cin helps peo­ple over­come shy­ness, in­creases their trust in oth­ers, and helps them read oth­ers’ emo­tion­al states bet­ter. But find­ings with ox­y­to­cin and em­pa­thy have been mixed. Some stud­ies have found that ox­y­to­cin in­creases peo­ple’s em­pa­thy for oth­ers in their own group—at the ex­pense of those out­side the group. That’s al­most the op­po­site of the new find­ings.

So why the in­con­sist­en­cy? 

It might have to do with the pre­cise func­tion of ox­y­to­cin, said the au­thors of the new stu­dy, Si­mone G. Shamay-Tsoory of the Uni­vers­ity of Hai­fa in Is­ra­el, Ah­mad Abu-Akel of the Uni­vers­ity of Bir­ming­ham in the U.K., and col­leagues. Re­search sug­gests ox­y­to­cin seems to make “so­cially rel­e­vant in­forma­t­ion” more viv­id in the view­er’s mind, they wrote, and the em­pa­thy ef­fects fol­low.

So if study par­ti­ci­pants have no par­tic­u­lar in­forma­t­ion about the oth­ers that they are deal­ing with, ox­y­to­cin might not in­crease em­pa­thy, they ar­gued. This may have been the case with some past stud­ies, where par­ti­ci­pants were di­vid­ed in­to “teams” but not pro­vid­ed any in­forma­t­ion about each oth­er.

“Our re­sults may have im­por­tant im­plica­t­ions for rec­on­cilia­t­ion and con­flict res­o­lu­tion,” the re­search­ers wrote. “While spec­u­la­tive, train­ing Is­rae­li and Pal­es­tin­ian mem­bers of the ne­go­ti­at­ing par­ties to con­sciously con­tem­plate the per­spec­tive of the oth­er,” they went on, could help cre­ate “an en­vi­ron­ment where peace is giv­en a chance.”

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Could inhaling something really help foster world peace, as some hippies claim? Don’t count on it. Yet a study has found that sniffing one special substance may make people feel more sorry for the suffering of outsiders, stigmatized people and outright enemies. That chemical is oxytocin, a hormone already naturally present in the brain and sometimes called the trust hormone. The study found that even people involved in one of the world’s most emotionally fraught conflicts, the Israeli-Palestinian struggle, seem to find a new heart for the other side after they inhale oxytocin. But the findings also run counter to those of past studies in some ways, suggesting that biologists are only beginning to clarify the function of the fascinating hormone known to play a role in social behavior and bonding in both humans and animals. “Oxytocin remarkably increased empathy to the pain of Palestinians” among Jewish Israelis in an experiment, wrote researchers, reporting their findings Sept. 22 online in the journal Psychoneuroendocrinology. The increased empathy reduced the participants’ “in-group bias,” they added—the predominant tendency of people to show more empathy for “those who they perceive as similar to themselves.” In their report, the researchers said they recruited 55 Jewish Israelis. These participants were shown some photos of people in painful situations, such as having a car hood closed on a hand, and other photos of people in non-painful situations. Labels with the photos indicated that the pictured person was from one of three groups. Either he or she was another Israeli Jew; or an Arab—often viewed as the “enemy” group for Israelis; or a European, chosen as a middle-ground group. The participants viewed the photos after having taken either oxytocin or an inactive substance, and were later assessed for how much empathy they showed to the people pictured. Oxytocin significantly increased participants’ empathy for the Arabs in pain, while leaving unchanged their empathy for the other two groups in pain, the researchers found. That suggests, they added, that oxytocin doesn’t necessarily make people empathize more with those they already empathize with. The experimenters measured viewers’ empathy by asking them to rate how much pain they thought the pictured person was experiencing. Past studies indicate that taking oxytocin helps people overcome shyness, increases their trust in others, and read other people’s emotional states better. But findings with oxytocin and empathy have been mixed. Some studies have found that oxytocin increases people’s empathy for others in their own group—at the expense of those outside the group. That’s almost the opposite of the new findings. So why the inconsistency? It might have to do with the precise function of oxytocin, said the authors of the new study, Simone G. Shamay-Tsoory of the University of Haifa in Israel, Ahmad Abu-Akel of the University of Birmingham in the U.K., and colleagues. Research suggests oxytocin seems to make “socially relevant information” more vivid in the viewer’s mind, they wrote, and the empathy effects follow. So if study participants have no particular information about the others that they are dealing with, oxytocin might not increase empathy, they argued. This may have been the case with some past studies, where participants were divided into “teams” but not provided any information about each other. “Our results may have important implications for reconciliation and conflict resolution,” the researchers wrote. “While speculative, training Israeli and Palestinian members of the negotiating parties to consciously contemplate the perspective of the other,” they went on, could help create “an environment where peace is given a chance.”