Science gives beauty some of its mystery back - for now
Jan 04,2008 00:00 by World Science Staff

What is phys­i­cal beau­ty, in a per­son?

In re­cent years, much sci­en­tif­ic opin­ion has gath­ered in sup­port of a some­what dreary an­swer: beau­ty is just the av­er­age. 

There’s something to that, stud­ies show. Vol­un­teers gen­er­ally rate “av­er­age” faces, crea­ted by com­pu­ters as composites of many others, as bet­ter-look­ing than un­u­sual faces. Blend­ing even just a few faces—even un­at­trac­tive ones—tends to pro­duce sur­pris­ing im­prove­ments. (Try it your­self
here).

(a), composite of 60 faces; (b), of the 15 “most attractive.” (Courtesy L. DeBruine et al.)

But if it’s dis­heart­en­ing to pon­der the idea that our fan­tasies cen­ter on a qua­li­ty so, well, av­er­age—take heart. A new study may have re­stored a tou­ch of the old mys­tery that beau­ty once had. 

Psy­chol­o­gists have found what would seem to be a slight but def­i­nite dif­fer­ence be­tween av­er­age faces and the most love­ly, as rat­ed by vol­un­teers.

“There are spe­cif­ic non-av­er­age char­ac­ter­is­tics that are par­tic­u­larly at­trac­tive,” wrote the re­search­ers, de­tail­ing their find­ings the De­cem­ber is­sue of the Jour­nal of Ex­pe­ri­men­tal Psy­chol­o­gy: Hu­man Per­cep­tion and Per­for­mance. “Our re­sults sug­gest that while av­er­age­ness is one com­po­nent of at­trac­tiveness, there is at least one oth­er... not ex­plain­a­ble by av­er­age­ness.”

The study did­n’t delve in­to deeper ques­tions beau­ty rai­ses: for in­s­tance, just what that non-av­er­age com­po­nent could be; and what beau­ty’s ev­o­lu­tion­ary func­tion might be (many sci­en­tists agree it probably helps sig­nal good health, though ex­actly how is un­cer­tain.) 

But the new find­ings did high­light the pos­si­bil­ity that even the lim­it­ed sci­en­tif­ic agreement sur­round­ing such is­sues may be prem­a­ture. A pre­vi­ous stu­dy, for in­stance, sug­gested beau­ty is that which the brain finds easy to pro­cess. But that con­ten­tion de­pended largely on the as­sump­tion that beau­ty is an av­er­age; the brain pre­sumably finds that easy to grasp, be­cause av­er­age is typ­i­cal.

In chal­leng­ing the beau­ty-as-av­er­age­ness hy­poth­e­sis, the new study was­n’t break­ing en­tirely new ground. At least one past study has al­so chal­lenged it. But crit­ics had ques­tioned the con­clu­sions of that work. The new study claimed to shore up some of the weak­nesses that spurred those doubts.

In that 1994 stu­dy, re­search­ers from the Un­ivers­ity of St. An­drews, U.K., av­er­aged 60 im­ages of faces with a com­put­er. They then sep­a­rately av­er­aged the 15 faces that vol­un­teers had judged as best-look­ing of the bunch. It turned out peo­ple rat­ed this smaller av­er­age as hand­som­er than the full-group av­er­age, rais­ing doubts about beau­ty as a sim­ple av­er­age.

But oth­er sci­en­tists raised ques­tions. Could­n’t it be—they asked—that the top 15 faces were in­deed so av­er­age, that their com­bina­t­ion re­flected the av­er­age of the hu­man race even bet­ter than the whole 60? The new­est study at­tempted to set­tle the ques­tion by re­peat­ing the ex­pe­ri­ment, but adding sev­er­al oth­ers to serve as strict tests of the in­i­tial re­sult.

The re­search­ers, Li­sa M. De­Bru­ine at the Un­ivers­ity of Ab­er­deen, Scot­land and col­leagues, again made an av­er­age of 60 faces—all white fe­males—and a sep­a­rate av­er­age of the 15 “pret­ti­est.” View­ers again rat­ed this as more al­lur­ing than the full-group com­pos­ite.

Fur­ther tests, the re­search­ers said, so­li­di­fied the con­clu­sion that av­er­age and gor­geous weren’t quite the same. For ex­am­ple, view­ers them­selves in­de­pend­ent­ly rec­og­nized the larg­er av­er­age as be­ing “more av­er­age” than that of the smaller group, ap­par­ently con­tra­dict­ing the idea that the smaller com­pos­ite might have been the tru­er ul­ti­mate av­er­age.

In anoth­er test, De­Bru­ine and col­leagues sub­jected their hap­less vol­un­teers to a bar­rage of at­trac­tive-face im­ages. Pre­vi­ous stud­ies had found that look­ing at many im­ages of one type, tem­po­rarily skews what view­ers con­sid­ers “av­er­age” to­ward that type. Thus, the re­search­ers rea­soned, if the beau­ty-is-just-av­er­age hy­poth­e­sis is cor­rect, then the vol­ley of win­some im­ages should have per­suaded vol­un­teers to see ad­di­tion­al beau­ti­ful faces as even more at­trac­tive—be­cause they look more av­er­age. 

In­stead, they wrote, the op­po­site hap­pened: the view­ers saw new im­ages of si­m­i­lar faces as slightly uglier than be­fore.

Yet anoth­er test served as some­thing of a probe of just how far from av­er­age “i­deal beau­ty” might be, to view­ers. The ap­par­ent ans­wer: even furth­er than the ear­lier ex­per­i­ment sug­gested.

The sci­en­tists used a com­put­er to iden­ti­fy the dif­fer­ences be­tween the or­di­nary av­er­age and the “at­trac­tive” av­er­age, then ex­ag­ger­ate those dif­fer­ences. That is, the ma­chi­ne took the “at­trac­tive” com­po­site, and dis­tort­ed it by am­pli­fy­ing what it had cal­cu­lat­ed as the beau­ti­ful char­ac­ter­is­tics. By de­grees, the chi­n got smaller; the nose nar­rower and more button-like. Event­ual­ly, the face started look­ing just bi­zarre. 

But be­fore that, some­thing in­ter­est­ing hap­pened. The study volunteers kept lik­ing the im­ages more and more un­til they were dis­tort­ed by some­where be­tween one-and-a-half times, and twice, the ini­tial “av­er­age-beau­ti­ful” diff­er­ence. Only after that did peo­ple start to call the pic­tures uglier in­stead of pret­ti­er. 

In oth­er words, the re­search­ers wrote, “at some point, car­i­ca­tur­ing an at­trac­tive shape will re­sult in a face that is so ab­nor­mal that con­cur­rent pref­er­ences for av­er­age­ness will out­weigh pref­er­ences for the at­trac­tive shape di­men­sion.” To put it more simp­ly, Plain Jane is not with­out her charm.

Courtesy of World-Science