Love:

Positivityresonanceasafresh,evidence-basedperspectiveonanage-oldtopic

BarbaraL.Fredrickson

UniversityofNorthCarolinaatChapelHill

RUNNINGHEAD:Love

ChaptertoappearinL.F.Barrett,M.Lewis,andJ.M.Haviland-Jones(Eds.)

HandbookofEmotions,4thEd.NewYork:GuilfordPress.

Love:

Positivityresonanceasafresh,evidence-basedperspectiveonanage-oldtopic

Whatislove?Humanshaveponderedthemeaningofthissplendored

phenomenonformillennia.Anythingthatsoreliablystirsthehumanheart,

preoccupiesthemind,andignitespassionateactioncertainlymeritsthislong-

standingandcontinuedinquiry.Artisticexpressionsofwhatloveisandhowit

worksabound–inpoetry,books,songs,andmovies.Scientificperspectivesareless

prevalent.Althoughscientificpsychologybeganinthelate1800s,morethansix

decadesintothiscollectiveendeavor,HarryHarlow,thenpresidentoftheAmerican

PsychologicalAssociation,decriedthatpsychologistshad“failed”toadvancebeyond

poetsandnovelistsinunderstandingthe“wondrousstate”oflove,“deep,tender,

andrewarding”(Harlow,1958,p.673).Inthenearlysixdecadessincereceiving

thisfailinggrade,twostrandsofpsychologicalsciencehavetakenthelovequestion

seriously:Developmentalsciencehasinvestigatedhowloveemergesbetween

infantsandtheircaregivers(e.g.Ainsworth,1985;Stern,2008),andrelationship

sciencehasexploredromanticlove,includinghowearlychildhoodattachment

shapesadulthoodloverelationships(Hazan&Shaver,1987;Bartholomew&

Horowitz,1991;Mikulincer,Shaver,Sapir-Lavid,&Avihou-Kanza,2009).1

Neighboringemotionsciencelagsbehind.Althoughafewemotionscientists

havedevotedattentiontothelovequestionovertheyears(e.g.,Fehr&Russell,

1991;Gonzaga,Keltner,Londahl,&Smith,2001;Shaver,Morgan,&Wu,1996),

theseeffortshavenotgerminatedathrivingstudyoflovewithinaffectivescience.

Aslong-timelovescholar,ElaineBersheidrecentlynoted,“emotiontheoristshave

theirownproblems[indefiningemotions]andarenotyetinapositiontohelplove

scholars”(2010,p.8).Foremotionscientists,whobydefinitionfavorthestudyof

momentaryphenomena,lovemaywellseemtoolarge,tooall-encompassing,ifnot

toopop-culture.

Thelargenessofloveisevidentbythediversesetofpsychological

phenomenathatfitundertheumbrellatermlove:thepreoccupyingandstrong

desireforfurtherconnection,thepowerfulbondspeopleholdwithaselectfewand

theintimacythatgrowsbetweenthem,thecommitmentstoloyaltyandfaithfulness.

Indeed,whenonepersonsays,“Iloveyou”toanother,itcanpointtoanyorallofthe

above.Thatis,thisubiquitousutterancemayreflectastrongcravingforphysical

contactorproximity,orserveasameanstoinviteorsecuretheotherpersoninto

one’sinnermostcircleofsocialties,oritmaysignaladeepandabidingtrust,ora

commitmenttobeloyal.Yet,inadditiontodesire,bonds,intimacy,and

commitment,loveisanemotion–aphenomenonthatarisestoinfusebothmindand

bodyforamoment,andthendissipates.

Thischapterputsforthanewperspectiveonlove,onethatemanatesfrom

emotionscience.Thegoalistoprovideaconceptualframeworktosupportafresh

waveofempiricalresearchonthisreveredemotionalstate.Thisnewperspective

holdsthat,atitscore,loveisapleasantandmomentaryexperienceofconnection

withanotherperson(orpersons).Inthisframework,otherconstructsthatare

commonlytakenassynonymsof“love”–suchasdesire,bonds,intimacy,and

commitments–arecastasproductsoftheaccumulationoffleetingemotionalstates

oflove.Assuch,therangeofotherphenomenathatgobythename“love”–inboth

scientificandcommonlanguage–maybestbeseenaspartofalargeranddynamic

“lovesystem.”

Thehubconceptthatdrivesthisdynamicsystemisapotentandpleasant

emotionalstate.Likeallpositiveemotions,theemotionalstateofloveobeysthe

ancestrallogicofthebroaden-and-buildtheory(cf.Fredrickson,1998,2013a).

Love-the-emotionbroadensmindsetsbyexpandingpeople’sawareness,particularly

ofself-otheroverlap(Aron,Aron,&Smollen,1992;Waugh&Fredrickson,2006),

creatingperceptionsoftogetherness,connection,unity,oroneness.Love-the-

emotionbuildsresourcesforsurvivalbyforgingandstrengtheningpeople’ssocial

desire,bonds,intimacy,andcommitments.Eachoftheseotherconceptswithinthe

broaderlovesystemgrowsstrongerasmomentsoflove-the-emotionaccumulate.

Yetthecausalarrowsalsorunintheotherdirection.Eachoftheseotherconcepts

withinthemoreencompassinglovesystem–thedesire,thebonds,theintimacy,the

commitments–alsofacilitatesubsequentmomentsoflove-the-emotion,creating

thedynamicsofanupwardspiral.Putsimply,it’sfareasierfortwoormorepeople

toconnectwhentheirdesire,bonds,intimacy,orcommitmentsarepresentand

strong.

Perhapsit’snowonderthatlovehaspuzzledsomanyforsolong.Partofthe

confusionisthattheword“love”hasbeenaffixedtodifferentpartsofthislarger,

dynamiclovesystem.Aprimarymissionofscience,however,istopeerintocomplex

systemstodiscovertheordertherein.Wearenowequippedtousethelensesof

emotionsciencetosharpenourappreciationoflove.Theselensesaddtothe

understandingsoflovethatneighboringrelationshipscienceanddevelopmental

sciencehaveofferedbydrawingparticularattentiontothemomentarynatureof

love,itsbiologicalbases,andbyofferingtheframeworkandlogicofthebroaden-

and-buildtheoryofpositiveemotions.

Thesharperappreciationforlovetobedevelopedherealsoilluminatesthe

valueofmildorlow-intensityformsofthisconsequentialstate.Mildformsoflove-

the-emotionaretooofteneclipsedbytheoverwhelmingintensityofselectlove

experiences,theonesthatforgelife’sstrongestbonds,suchasthosebetweenan

infantandhercaregivers,orbetweentwonewromanticpartnersjustnow“falling

inlove.”Thestudyofpositiveemotions,however,cautionsresearchersnottobe

blindedbyintensity:Ampleempiricalevidencerevealsthatthefrequencyof

pleasantaffectivestatesisfarmoreconsequentialthantheintensityofthosestates

(Diener,Sandvik,Pavot,1991;Folkman,1997;Isen,1993),andthatthe

consequencesofmildpleasantaffectivestatesforhealthandwell-beingare

considerable(Cohn,Fredrickson,Brown,Mikels,&Conway,2009;Moskowitz,2003;

Fredrickson,Cohn,Coffey,Pek&Finkel,2008).Love-the-emotionlikelyfollowsthis

samepattern.Mildyetconsequentialformsoflovecaninfuseeverydaypositive

connectionsbetweenandamongfamily,friends,acquaintances–evenstrangers–to

forgeandfortifybonds,alliances,meaning,andpurpose,aswellascommunityand

collectivehealthandwell-being.

TowardaFormalDefinitionofLove-the-Emotion

ViewsfromEmotionScience

Emotionscientistsdistinguishbetweenloveexperiencesandlove

relationships(Lazarus,1991),anddirecttheirfocustotheformer,thetransient

feelingstatesoflove,ratherthanthelatter,thelong-standingsocialtiesthatare

infusedwith,andsupportedbylove-the-emotion.Evenso,itbearsunderscoring

thattransientexperiencesoflovearefelttowardandwithspecificindividuals(e.g.,

one’smother,friend,lover,orchild),andarethereforecontextualizedbythese

interpersonalconnections.Manytheoristshavepointedoutthatloveisnotactually

asingleemotionalstate,butrathercomesinmultipleforms,somemoretenderand

low-key,andothersmorejoyfulandhigh-energy.AsRempelandBurris(2005)put

it,“loveseemstobereflectedinmultipleemotionsratherthanonedistinctemotion”

(p.298).Supportingthisview,inexamining14pleasantemotions,Ellsworthand

Smith(1988)foundthatlovewasamongtheleastdifferentiated.

WhereasRempelandBurris(2005)uselove’slackofspecificitytoarguethat

loveisnot,infact,anemotion,othertheorists,likeIzard(1977)andFredrickson

(1998)usethissameobservationtosupportadifferent,contextualizedviewoflove.

Thisalternateviewholdsthatexperiencesoflovecanbeseenastheexperienceof

anyotherpositiveemotionwhenthatemotionisfeltinthecontextofasafe,often

closerelationship.ForIzard(1977),whoatthetimeidentifiedonlyinterestandjoy

asamongtheotherpositiveemotionsheconsidered,lovewastakentobethejoy

andinterestthatpeoplefeelinconnectionwithothers.Inhiswords,“acquaintances

orfriendsrenewyourinterestbyrevealingnewaspectsofthemselvesandthe

resultingincreaseinfamiliarity(deeperknowledgeoftheperson)bringsjoy.In

lastingfriendshipsorloverelationshipsthiscycleisrepeatedendlessly”(1977,p.

243).

Morerecently,Fredrickson(2009)expandedonIzard’s(1977)illustrationto

includeeightadditionalpositiveemotionsalongsidetheappraisalpatterns

associatedwitheach,arguingthateachofthesemomentsmightbeequally

describedaslove:

Intheearlystagesofarelationship,tiedupwithyourinitialattraction,you’re

deeplyinterestedinanythingandeverythingthisnewpersonsaysanddoes.

Youshareamusementsandlaughtogether,oftenasaresultofthe

awkwardnessofcomingtogetherforthefirsttime.Asyourrelationship

buildsandperhapssurpassesyourexpectations,itbringsgreatjoy.Youbegin

toshareyourhopesanddreamsforyourfuturetogether.Astherelationship

becomesmoresolid,yousinkbackintothecozyserenity[contentment]that

comeswiththesecurityofmutuallove.You’regratefulforthejoysyour

belovedbringsintoyourlife,asproudoftheirachievementsasyouareof

yourown,inspiredbytheirgoodqualities,andperhapsinaweoftheforcesof

theuniversethatbroughtyoutwotogether.(Fredrickson,2009,p.47).

FollowingIzard’sfootsteps,myearliestscholarlydescriptionoflove-the-

emotiontookan“alloftheabove”approach,definingitasanypositiveemotionfelt

inthecontextofasafe,oftencloserelationship(Fredrickson,1998).AlthoughIstill

holdthatacknowledgingthemanydifferentflavorsoflove-the-emotionisavital

step,fortworeasons,Inowseethatthisstepisn’tnearlybigenough.Firstand

foremost,thisearlierconceptualizationremainsaone-personpsychology,

positioningtheotherpersonasmerelythe“context”forthefocalperson’s

experienceoflove.Aricherunderstandingoflove-the-emotionemergeswhenwe

widenthelenstoalsoincludewhattheotherpersonis,atthatsamemoment,

feeling.Steppinguptothistwo-personpsychology,2Inowmorespecificallyposition

love-the-emotionasemerginganytimeapositiveemotionismomentarilysharedby

two(ormore)individuals.Second,Ifindtheemphasisonestablishedclose

relationshipstobelimitingandunjustifiable.Initialorone-timeconnectionswith

novelinteractionpartnerscanalsosupporttheemergenceofsharedpositive

emotions.Thedifferencesbetweentheseconnectionsandthosethatemergewithin

closerelationshipsmaybelargelyamatterofdegree,ratherthankind.

So,toexpandthescopeofpastconceptualizationsoflovewithinemotion

science,Ipositherethatonecoreelementoflove-the-emotionissharedpositive

emotions.Tolaythefoundationfortwoadditionalcoreelements,Ioutlineviews

offeredbyrelationshipscienceanddevelopmentalscienceinturn.

ViewsfromRelationshipScience

Adominantapproachwithinrelationshipscienceistodemarkdifferenttypes

ofloverelationships.Berscheid(2010),forinstance,identifiescompanionate,

romantic,compassionate,aswellasattachmentloverelationships(seealsoHatfield

&Rapson,1993;Sternberg,1986;Fehr,Sprecher,&Underwood2008;Fisher,Aron,

Mashek,Li,&Brown,2002).Recentadvancesinunderstandinglove,forinstance,

haveexploredtheuniqueneuralcorrelatesofromanticversuscompanionatelove

(Acevedo,Aron,Fisher&Brown,2012).

Whereasthesevariousformsoflovecertainlydifferfromoneanother,they

alsosharecertainfamilyresemblances.Incontrasttothedominantapproachof

definingloveasaprototype(Fehr1988;Shaver,Schwartz,Kirson&O’Connor,

1987),recentworkbyHegiandBergner(2010)attemptstoarticulateaformal

definitionoflove,onethatidentifiesnecessaryandsufficientconditionsforusing

thewordlovecorrectlyacrossarangeofloverelationships.Buildingonworkby

Clarkandcolleaguesoncommunalrelationships(Clark&Mills,1979;Clark&

Monin,2006),aswellasworkbySinger(1984)andRempelandBurris(2005),Hegi

andBergner(2010)hypothesizethatessentialtoarangeofloverelationships–

companionate,romantic,compassionate,andattachment–is“investmentinthe

well-beingoftheother,forhisorherownsake”(Hegi&Bergner,2010,p.621).

Theydrawsupportfortheirhypothesisfromsurveysthatcapturerespondents’

schemasforwhatcountsaslove.Specifically,respondentsconsiderhypothetical

examplesofdifferenttypesofrelationshipsinwhichacertainrelationship

characteristicismissingonthepartofoneindividualintherelationship,and

indicatethedegreetowhichtheywouldfinditcontradictorytosaythatthisperson

lovestheotherunderthosecircumstances.Inexaminingrelationshipcharacteristics

rangingfromsimilarityandtrusttoexclusivityandenjoyment,theyfoundthatonly

theabsenceof“investmentinthewell-beingoftheotherforhisorherownsake”

wasdeemed“verycontradictory”tothepresenceofaloverelationshipbythevast

majorityofrespondents(Hegi&Bergner,2010).Theauthorsusethesedatato

arguethatsuchinvestmentisanecessaryandessentialfeatureofhumanloveof

variouskinds.Assuch,love,bydefinition,conveysacaringorientationtoward

others.

Theinterpersonalcounterparttolove’scaringorientationtowardtheother

appearstobetheconceptof“perceivedpartnerresponsivenesstotheself,”which

reflectstheextenttowhichtheotherpersonregistersthatheorsheisbeing

attentivelycaredfor(e.g.,Reis,Clark,&Holmes,2004).Thatis,totheextentthat

PersonAinvestsinthewell-beingofPersonB,forB’sownsake,PersonBmaycome

tobelievethatPersonAunderstandsandvalueshimorher,andresponds

supportively.Perceivedpartnerresponsivenessispositionedas“acardinalprocess

inclosenessandintimacy”(Reisetal,2004,p.220;seealsoLaurenceau,Barrett,&

Pietromonaco,1998),particularlywithincommunalrelationships.Assessmentsof

thedegreetowhichanotherpersonunderstands,caresfor,andvalidatesyouinform

youroverarchingbeliefthatthisotherpersontruly“getsyou,”anduseshisorher

privilegedknowledgethoughtfully,foryourbenefit.Responsiveparentingisalsoa

cornerstoneconceptwithinattachmenttheory(Bowlby,1969/1982),withstudies

showingthatparentalresponsivenesstoachild’sneedsistherootofsecure

attachmentandthedevelopmentofstableandpositiveinternalmodelsofselfin

relationtoothers(Bowlby,1969/1982;Ainsworth,Blehar,Waters,&Wall,1978),

whichinturnshapethoughts,emotions,andbehaviorthroughoutchildhoodand

intoadulthood(Mikulinceretal.,2009).

Researchonperceivedresponsivenessunderscoresthatloveisnota

unidirectionalphenomenon,concerningoneperson’sfeelingstowardanother,butis

insteadabidirectionaltransaction,inwhicheachperson’sperceptionsoftheother’s

feelingstowardtheselfarealsovitaltotheemergenceofintimacy.Responsiveness

isknowntobeconsequentialacrossarangeofemotionalexchanges.Forinstance,

whenonememberofaromanticcouplethankstheother(Algoe,Fredrickson,&

Gable,2013),orreactsastheothersharessomepersonalgoodfortune(Gable,

Gonzaga,&Strachman,2006),theextenttowhichtheotherpersonperceivesthat

thanksorthatreactiontoberesponsiveforecastsfuturerelationalwell-being,and

eventhelongevityoftherelationship.Responsivenessmayalsobeconsequentialto

physicalhealth.AnationalU.S.surveyofindividualsofmarriedorcohabitatingwith

aromanticpartnerfoundthathighreceivedemotionalsupportfromthepartneris

associatedwithincreasedmortalityriskforthosewhoratetheirpartnersaslacking

responsiveness,whereasthisriskisabsentamongthosewhoratetheirpartnersas

highinresponsiveness(Selcuk&Ong,2013).

Althoughmoststudiedwithincommunalrelationships,responsiveness–and

theperceptionofit–canalsocharacterizeexchangerelationships,evenone-time

encounterswithstrangers.Asatravelertoanunfamiliarcity,forinstance,youmay

cometoappreciatethatthebaristawhomakesyourmorningbrewisespecially

attunedtoyourwishesandmood,eagertopleaseandconnect.Asyoumakeyour

economictransaction,thetwoofyousmileandchatwitheaseandopenness.

Walkingawayfromthisexchange,youmightfeelmoreupliftedandenergizedthan

you’dfeltjustmomentsago.Duttonandcolleaguesdescribesuchencountersas

high-qualityconnections,orHQCs(Stephens,Heaphy,&Dutton,2012;seealso

Heaphy&Dutton,2008).HQCsareshort-term,positiveinteractionsthatare

experiencedasenlivening,characterizedbymutualperceivedresponsiveness.

Althoughthesepositiveencountersmaybepartofongoingrelationships,theyneed

notbe.Theycanalsoreadilyemergewithinone-timeencounterswithshopkeepers

orcustomers,healthcareprovidersorpatients,oranytimetwoormorepeople

interact.

Rapportisalsocommonlyusedtodescribethesortsofpositiveconnections

thatemergebetweenandamongpeoplewhoaresaidto“click”orhave“chemistry.”

Conceptually,rapportisanemergent,interpersonalphenomenonmarkedbymutual

attentiveness,positivity,andcoordination(Tickle-Degnen&Rosenthal,1990),all

thehallmarksofresponsiveness.Nonverbally,rapportisembodiedthroughmutual

directbodyorientationandgaze,accompaniedbysmiles,nods,forwardleans

(Tickle-Degnen&Rosenthal,1990)aswellasbehavioralsynchrony

(Vacharkulksemsuk&Fredrickson,2012).Whereastheconcept“love,”inits

traditionalusage,tendstoimplylong-standingintimaterelationships,theconceptof

“rapport”allbutimpliesalackofintimacyandhistory.Bycontrast,Iholdthatthe

conceptsof“love”and“rapport”maydifferprimarilyindegree,ratherinkind,and

thatitmaybemoregenerativetoconsiderthemasexamplesofthesameunderlying

biopsychosocialphenomenon.

Forthepresentpurposes,Idenotethereciprocalcombinationof“investment

inthewell-beingoftheother,forhisorherownsake”and“perceivedpartner

responsivenesstotheself”bytheshorthandphrasemutualcare.Althoughmutual

careisperhapsmostobviouswithinpeople’slong-standingloverelationships–

with,forinstance,romanticpartnersandotherfamilymembers–itisnotan

exclusivepropertyofthesecommunalrelationships.Inmilder,perhapsless

obviousforms,mutualcarecanalsoinfusemorecasualencounterswithfriends,co-

workers,acquaintances,evenstrangers.Indeed,anytimeembodiedrapportor

high-qualityconnectionsemerge,mutualcareis,bydefinition,present.Importantly,

thiscareisneitherheavy-handednorrole-bound,asinbeingacaregiver.Ratherit

isaslight,nonconscious,andmomentaryastheunbiddenconcernyou’dfeelifthe

personwithwhomyouwereconnectingsuddenlyhadaheavyobjectfallonheror

hisfoot:you’dwincetoo,thenquicklyassessyourcompanion’swell-being.Mutual

caredescribesastateinwhicheachpersonwouldshowthisminimallevelof

engagementwith,concernfor,andinvestmentinthewell-beingoftheother.Iposit

thatmutualcareisasecondcoreelementoflove-the-emotion.

ViewsfromDevelopmentalScience

Ifmutualcare–withitshallmarkmutualconcernfortheother’swell-being

andmutualperceivedresponsiveness–istakenasanadditionalcoreelementof

love-the-emotion,itmightseemthatencountersorrelationshipsthatinvolve

dependenceorasymmetry–aswithaninfant,orchild(oranotherwiseneedy

individual)withaparentorcaregiver–areruledoutofsuchmutuality.While

dotingparentsclearlylovetheirnewborns,cantheirnewbornstrulylovethem

back?Withtheirlimitedcapacities,howcannewbornsmusteruptheselflessother-

focusthatdefineslove?

Thewayoutofthisseemingconundrumistorecognizethatwarmth-infused

other-focusrequiresnomusteringatall.Rather,itunfoldsautomaticallyand

effortlessly,completelywithouthighersymbolicoreffortfulmentalprocesses.

Indeed,developmentalpsychologistshavearguedthat,frombirth,infantsare

biologicallypreparedtoperceivecross-modalcorrespondencesbetweenwhatthey

seeontheirinteractionpartners’facesandwhattheysense,proprioceptively,on

theirownfaces(Meltzoff&Moore,1989;Trevarthen,1998).Thisabilityiswhat

enablesinfantstosynchronizetheirmovements–inform,tempo,andintensity–

withthoseofothers,totheextentthattheirmotorcontrolallows(Meltzoff&Moore,

1989).

Notably,behavioralsynchronygoesbeyondmimicrybecausematchingoften

occursacrossmodalities,suchaswhentherhythmofaninfant’smovementssync

upwiththerhythmofhermother’svocalizations.Suchcross-modalanalogiespoint

toaresonancebetweeninfantsandtheirinteractionpartnersatthelevelof

subjectivemindstatesandemotions,andnotmerelyatthelevelofobservable

behaviors.Behavioralsynchronycanthusbetakentorevealanintersubjectivity

(Beebe,Sorter,Rustin,&Knoblauch,2003),oraffectiveattunement(Stern,1985),

describedasaninnateformofintimacy,awaytofindandshowdelightin

communing,connecting,orbeingwithanother.Throughsuchaffectivesharing,an

infant“experiencesbeingexperienced”(Beebeetal.,2003,p.786)or“feel[s]felt”by

theother(Siegel,2001,p.78),amomentaryexperienceakintowhatrelationship

scientists,asdescribedabove,havetermed“perceivedpartnerresponsivenessto

theself.”Importantly,“feelingfelt”isitselfapositiveemotionalexperience(Beebe

etal.,2003).

Developmentalsciencehasalsoshownthattheattentivedanceofbehavioral

synchronythatemergesbetweeninfantsandtheirresponsivecaregivers–adance

lacedwithsmiles,coosandothergesturesofpositivity–isabsolutelyvitaltonormal

humandevelopment,asvitalagoodnutrition(Stern,1985;Siegel,2001).Theclassic

“still-faceparadigm,”forinstance,revealshowavidlyinfantsseekitout.

Researcherswhousethisparadigminviteparent-infantdyadstothelaboratoryto

videotapethemduringtypicalface-to-faceplay,afterafewminutesofwhichthe

researcherssignaltheparenttoadoptastill,neutralface,whilemaintainingeye

contactwithherorhisinfant.Theparent’sstillfacesendsamixedmessagetothe

infant:theparent’sgazesignalsreadinesstoengage,yetherorhispassiveface

conveysunavailability.Behavioralcodingofinfantresponsestothestill-face

paradigmrevealsthat,inthefirsthalf-minuteorso,infantstypicallycontinueto

gazeandsmileattheirparent,making“positivebids”forreengagement.These

hopefulbidsaredestinedtofail,however,becauseparentsareinstructedto

maintainapassivefacefortwominutes.Facedwiththisfailure,theinfants’

positivitytypicallywanesandgiveswaytonegativity,markedbyloweredbrows

andopen-mouthcries(Ekas,Haltigan,&Messinger,2013).

Moresoberingevidenceforthedevelopmentalnecessityofthepositive

intersubjectivitysignaledbybehavioralsynchronycomesfromcaregiverswho

strugglewithdepression,whoarefarlesslikelytoshowthe“dance”ofbehavioral

synchronywiththeinfantsintheircare.Studiesshowthatdepression,whichaffects

10-12percentofpostpartummothers,slowsbothspeechandbodymovements,and

disruptsparent-infantsynchrony(Feldman,2007).Widelyviewedasadisorderof

thepositiveemotionsystem(Davidson,2000),depressionstiflestheemergenceof

intersubjectivityandsharedpositivity.Ampleresearchconfirmsthatmaternal

depressionininfancyforecastsachild’simpairmentsincognitiveandsocio-

emotionalskillsevendecadeslater(forareview,seeFeldman,2007).

Morerecentevidencesuggeststhatpositivebehavioralsynchrony—the

degreetowhichaninfantandaparent(througheyecontactandaffectionatetouch)

laugh,smile,andcootogether—correspondswithoxytocinsynchrony.Researchers

havemeasuredoxytocinlevelsinthesalivaofdads,moms,andinfantsbothbefore

andafteravideotaped,face-to-faceparent-infantinteraction.Forinfant-parent

pairswhoshowmutualpositiveengagement,oxytocinlevelsalsocomeintosync.

Withoutsuchengagement,however,nooxytocinsynchronyemerged(Feldman,

Gordon,&Zagoory-Sharon,2010).

Basedontheaforementionedevidencefromdevelopmentalscience,Iposit

thatbiobehavioralsynchronyisathirdcoreelementoflove-the-emotion.

PushingEmotionScienceFurther:ANewHybridView

Distinct,albeitoverlapping,viewsoflovehaveemergedwithinthe

neighboringdisciplinesofemotionscience,relationshipscience,anddevelopmental

science.Furtherintegratingtheseviews,Iproposeanewhybridviewthatpositions

loveasamomentaryemotionalphenomenonthatisco-experiencedbyanytwoor

moreinteractingpeople.Distillingtoaformaldefinition,Idefinelove-the-emotion

asamicro-momentofpositivityresonance,duringwhichthreecoreelements–(1)

sharedpositiveemotion,(2)mutualcare,and(3)biobehavioralsynchrony–emerge

withtemporalcoherencebetweenandamongpeople.

Departingfromrelationshipscience,love,asconceptualizedhere,isnotan

enduringorintimaterelationship.Inkeeping,however,withtheadaptationistlogic

ofthebroaden-and-buildtheoryofpositiveemotions(Fredrickson,1998,2013b),

micro-momentsofpositivityresonancefertilizethegrowthofconsequential

personalandsocialresources,includingenduringcloseandintimaterelationships

aswellasmentalandphysicalhealth.

Takingacuefromrelationshipscience,Ialsoelevatemicro-momentsof

positivityresonanceabovetheexperiencesofotherpositiveemotions.Thatis,I

hypothesizethatpositivitythatresonatesbetweenandamongpeopleisparticularly

efficientforbuildingconsequentialresources,relativetopositiveemotionsthatare

experiencedinisolationorabsenttheelementsofmutualcareandbiobehavioral

synchrony.Accordingly,Ihavecalledoutloveas“oursupremeemotion”

(Fredrickson,2013a).Thisapproachdepartssharplyfromanunspokentradition

withinemotionscience,whichimplicitlytakespecific,discernableemotions–fear,

anger,joy,andpride–asroughlyequal-statuscategories,eachholdingvaluefor

humansurvivalinitsownway.Underthistraditionallogic,noemotion,love

included,issetapartasonadifferentplane,orscaleofimportance.Bycontrast,

relationshipscienceunabashedlypositionsloverelationshipsasdistinctfromother

relationshipsandmoreconsequentialtohumanwelfare.Likewise,foritsabilityto

weaveindividualsintothesocialfabricofcommunity,love-the-emotionmaywellbe

moreconsequentialtohumanwelfarethananyotheremotion.

MileageGainedfromtheConceptofPositivityResonance

PreconditionsforPositivityResonance

Micro-momentsofpositivityresonancebetweenandamongpeopledonot

emergeatrandom,regardlessofconditions.Inthisway,loveisnotunconditional.(I

acknowledgethatIdeploytheterm“unconditional”inadifferentmannerthanhave

humanisticpsychologists.)Love’sfirstprecondition,Iposit,isperceivedsafety.As

formostpositiveemotions,momentaryperceptionsofsafetyappeartobean

importantprerequisite.Whenpeopleappraisetheircurrentcircumstancesas

somehowthreateningordangerous,theabilitytoshareanexperienceofpositivity

resonancebecomeshighlyimprobable.Fortunately,truethreatstosafetyare

statisticallyrare:Mostmomentsarebenign(Oishi,Diener,Choi,Kim-Prieto,&Choi,

2007).Yet,unfortunately,manypeopledonotexperiencethesafetyinwhichtheir

livesareembedded.Thosewhosufferfromanxiety,depression,loneliness,orlow

self-esteem,forinstance,perceivethreatsfarmoreoftenthantheirobjective

circumstanceswarrant(e.g.,Cacioppo&Hawkley,2009).Thisover-alertstate

thwartstheemergenceofallpositiveemotions,includinglove.Moregenerally,the

inabilitytoexperiencesafetyinthecompanyofothersisapoignantobstacletolove.

Love’ssecondprecondition,Iposit,issensoryconnection.Neitherabstract

normediated,sensoryconnectionisphysicalandunfoldsinrealtime.Itrequiresthe

co-presenceofbodies,throughtouch,voice,orvisiblysynchronizedpostures,

gestures,orfacialexpressions.Arguably,however,themainmodeofsensory

connectioniseyecontact(Farroni,Csibra,Simion,&Johnson,2002).Newborns,for

instance,showanimmediatepreferenceforeyecontact,aswellasinnateskillsfor

establishingitwiththeadultswhocomeintotheirvisualrange.Eyecontactisalsoa

gatewayconstructwithinthesimulationofsmiles(SIMS)model,articulatedby

Niedenthalandcolleagues(Niedenthal,Mermillod,Maringer,&Hess,2010).Making

eyecontactwithsomeonewhosmiles,accordingtotheSIMSmodel,triggersarapid

andnonconsciousembodiedsimulationofthatsmile–throughfacialmimicryand

neuralactivation–thatimplicitlyfunctionstodisambiguatethemeaningofthat

smile.InsupportoftheSIMSmodel,controlledlaboratoryexperimentsconfirmthat

mutualeyegaze,relativetoavertedgaze,triggersfacialmimicrytodynamic

emotionalstimuli(Schrammel,Pannasch,Graupner,Mojzisch,&Velichkovsky,

2009),andthatfacialmimicryenablesmoreaccuratedecodingofthegenuineness

ofdynamicsmiles(Maringer,Krumhuber,Fischer,&Niedenthal,2011).These

processesmayaccountinfants’abilitytodetectinauthenticemotions(Walle&

Campos,2014).Totheextentthateyecontactduringemotionalepisodestriggers

embodiedsimulations,infants’prescientskillsformakingeyecontactcanbeviewed

asevolvedadaptationsthathelpinfantswordlesslyandaccuratelyconveytheir

ever-shiftingemotionalneedstoengagedcaregivers(Niedenthaletal.,2010).

Throughsensoryconnection,then,positiveemotions“jumpthegap”between

peopletobecomesharedexperiencesofpositivityresonance,markedbiobehavioral

synchronyandmutualcare.

ProductsofPositivityResonance

Eventhoughmicro-momentsofpositivityresonanceareoftenmildandby

definitionfleeting,theaccumulatedfrequencyoftheseexperiencesovertimebuilds

arangeofresourcesimportanttosubjective,relational,andphysicalwell-being.For

instance,theexperienceofpleasureor“liking”precedesandlaysthefoundationfor

desireor“wanting”(Berridge,2007).Inthecaseofpositivityresonance,the

pleasureoffeelingconnectedtoanewromanticpartneror“crush,”assessedasself-

otheroverlap(Aron,Aron,&Smollan,1992),prospectivelypredictsthefrequencyof

positiveautomaticthoughtsaboutthatperson,whichcanservetomotivate

subsequenteffortstoreconnect(Rice,Schenker,&Fredrickson,2014).Likewise

experiencingpositivityresonancewiththesamepersonrepeatedlyovertimebuilds

trustandloyalty,socialattitudesvitaltosuccessfulfriendshipsandcommunity

alliances.Therecurrenceofpositivityresonancealsoseedsthemotivationfor

secureattachments,socialbonds,andmoreformalcommitmentstoloyaltysuchas

marriage(Cohn&Fredrickson,2006;Brown&Brown,2006).Asstatedpreviously,

theseenduringresources–desire,bonds,andcommitments–arethemselves

identifiedas“love”inbothscientificandlaywritings.Increasingscientificprecision,

Iofferpositivityresonance(love-the-emotion),astherecurrentbiopsychosocial

mechanisms,or“tinyengines,”thatdrivealargerlovesystemthatalsoincludes

thesemoreenduringproductsofpositivityresonance.

EvidenceforPositivityResonance

Arangeofconvergingevidenceinspiredmetoformulatetheconceptof

positivityresonanceandarticulatekeyhypothesesaboutit.Withinmyown

laboratory,theworkofTanyaVacharkulksemsukhasbeenfoundational

(Vacharkulksemsuk&Fredrickson,2012).SheandIstudiedpairsofpreviously

unacquainteddyadsthatwehadrandomlyassignedtocompleteoneoftwo

interactiontasks,whichwevideotaped:eitheravariantofAron’sself-disclosure

inductionparadigm(Aron,Melinat,Aron,Vallone,&Bator,1997),oraneutral,

collaborativeproof-readingtask.Trainedcoderslaterviewedthemutedvideo

recordingsandratedtheextentofsimultaneousmovement,temposimilarity,and

coordinationandsmoothnessinthedyad’snonverbalbehaviors,whichwethen

summedintoanaggregateindexofbehavioralsynchrony.Welearnedthatthe

physicalanddynamicpropertyofbehavioralsynchronymediatedtheassociation

betweenself-disclosureconditionandsubsequentreportsofembodiedrapport,

evenwhencontrollingforreportsofpositiveemotion(Vacharkulksemsuk&

Fredrickson,2012).Ourevidencefortheimportanceofnaturally-occurring

behavioralsynchronycomplementsresearchthathasmanipulatedbehavioral

synchronytoshowthatitbreedsaffiliation(Hove&Risen,2009),cooperation

(Wiltermuth&Heath,2009),andcompassion(Valdesolo&DeSteno,2011).

Goingbeyondbehavioralsynchrony–andunseenwithinordinary

interactions–isthebiologicalsynchronythatemergeswhentwoormorepeople

shareapositiveemotionalstate.Aspreviouslymentioned,oxytocinsynchrony

arisesduringpositiveinteractionswithinparent-infantdyads(Feldmanetal.,

2010).Morecompellingstillisevidencefromrecentneuroimagingstudiesthat

showwidespreadneuralsynchronywithindyadsandgroupssharingapositive

emotionalexperience(Hasson,2010;Hasson,Nir,Levy,Fuhrmann,&Malach,2004;

Stephens,Silbert,Hasson,2010).Itappears,then,thatwhenpeopleshareapositive

emotionalstate,theyalsosharegestural,biochemical,andneuralpatterns.This

momentarybiobehavioralsynchronyunifiestheinteractingindividualswithina

sharedexperienceofpositiveresonance.

Twoadditionalstreamsofevidencealsocontributedtomytheorizingon

love.First,along-standingbodyofprospectivestudiesshowsthathavingdiverse

andrewardingsocialrelationshipsrobustlyforecastsbetterphysicalhealthand

greaterlongevity.Forinstance,arecentmeta-analysisof148studiesconcludesthat

theinfluenceofsocialintegrationonmortalityriskisonparwiththatofother,well-

establishedhealthriskfactors,includingsmoking,excessivealcoholintake,obesity,

andlackofphysicalexercise(Holt-Lunstad,Smith,&Layton,2010).Second,

conspicuouslysimilarprospectiveevidencelinksthefrequentexperienceofpositive

emotionstolivinglongerandhealthierlives(formeta-analyticreviews,seeChida&

Steptoe,2008,andHowell,Kern,&Lyubomirsky,2007).Unitingthesetwostreams

ofevidence,recentworkfrommylaboratoryshowsthatperceivedpositivesocial

connections–aproxymeasureofpositivityresonance–accountsforthe

relationshipbetweenpositiveemotionsandphysicalhealth(Kok,Coffey,Cohn,

Catalino,Vacharkulksemsuk,Algoe,Brantley,&Fredrickson,2013).Specifically,

people’sdailyexperiencesoffeeling“close”and“intune”withtheirsocial

interactionpartnersmediatedtheeffectofanexperimentalinterventionthattaught

studyparticipantshowtoself-generatepositiveemotions(vialoving-kindness

meditation,seealsoFredricksonetal.,2008)onimprovementsincardiacvagal

tone,aproxymeasureofphysicalhealth.Thus,itappearsthatwhenpeople’sefforts

tocultivatepositiveemotionsculminateinexperiencesofday-to-daypositivity

resonancewithothers,theyincurparticularbooststotheirphysicalhealth.Much

likeourday-to-dayhabitsofbeingphysicallyactiveandeatingnutritiousfoods,our

day-to-dayhabitsofcultivatingpositivityresonancewithothersmaywellfunction

aspositivehealthbehaviors.

ResearchAgenda

Researchontheconceptofpositivityresonanceremainsscant,tobesure.As

such,opportunitiesaboundtotestandrefinethisnewdefinitionoflove.Keytothe

successofthisworkwillbethedevelopmentofvalidandreliablemeasuresof

positivityresonancethathonoritsmomentaryandmultifacetednature.Although

self-reportmeasuresmaycapturethephenomenologicalaspectsofpositivity

resonance,nonverbalbehavioralandbiologicalmeasureswithappropriate

temporalresolutiongatheredfrominteractingdyadswillalsobeessential.In

addition,longitudinalresearchwillbeneededtotesttheclaimthatpositivity

resonancemeritselevationaboveotherpositiveemotionsinitsabilitytoaugment

well-beingandphysicalhealth.Longitudinalanddynamicstatisticalmodelingmay

beespeciallyrelevanttoolsasthisresearchareamatures.

TheoreticalImplications

Whatgoodisasmile?What’sitfor?Althougharangeofpasttheoristshave

addressedthesequestions,thenewconceptofpositivityresonanceoffersafresh

takeontheevolvedadaptivefunctionofspontaneousandgenuinesmiles–what

havebeentermedDuchennesmilesintheresearchliterature.FollowingCharles

Darwin(1872/1998),Ekmanandcolleaguescontendthatsuchsmilesevolvedasan

outwardexpressionorreadoutofaperson’sotherwiseunseeninnersubjective

state(Ekman,Davidson,&Friesen,1990).Anopposingviewshiftsthefocusonto

therecipientofasmile,andproposesthatsmilesevolvednotbecausetheyprovided

readoutsofpositiveemotionalstates,butinsteadbecausetheyevokedpositive

emotionsinthosewhomeetasmilingperson’sgaze(Owren&Bachorowski,2003;

seealsoGervais&Wilson,2005).Maintainingthefocusonthepersonwhomeets

thesmiler’sgaze,theembodiedcognitionperspectiveoftheSIMSmodelsuggests

that,throughneuralsimulation,smilestuneanobservertowardabetter

understandingthesmiler’ssubjectiveexperienceandmotives,sothattheperceiver

can,forinstance,disambiguatesincereaffiliativebidsfromdomineeringorself-

absorbedsmiles(Niedenthaletal.,2010).Eachoftheseaccountsofthefunctionof

genuinesmilesseemsviable,albeiteachremainsincompletebyremaininganchored

tooexclusivelywithinaone-personpsychology(focusedeitherontheoneperson

whosmilesortheonepersonwhowitnessesasmile).

Steppinguptoatwo-personpsychology,inwhichboththesmilingindividual

andthesmilerecipientplayequalandimportantroles,Iproposethatthefunctionof

atleastasubsetofDuchennesmilesis“alloftheabove”andthensome.Specifically,

theadaptivesignificanceofagenuine,affiliativesmilemaybetocreatea

momentarilyunifiedmindsetbetweentwopeople,orintersubjectivity,thatis

characterizedbypositivityresonance,asreflectedbythetriooflove’sfeatures:a

nowsharedpositiveemotion,biobehavioralsynchrony,andanorientationtoward

mutualcare.Researchdocumentsthatasmiledrawsoureyemorethanotherfacial

expression(Becker,Anderson,Mortensen,Neufeld,&Neel,2011).Aswe’veseen,

eyecontactnonconsciouslytriggersfacialmimicry(Schrammeletal.,2009),which

inturntriggersneuralsimulation(Niedenthaletal.,2010).Whentheoriginalsmile

emanatesfromasincereaffiliativebid,themomentaryintersubjectivitycreatedby

neuralsynchronywillincludeorientationstowardmutualcareandresponsivity.In

short,theevolvedadaptivesignificanceofgenuineaffiliativesmilesmaybetoseed

statesofpositivityresonance.Harkeningbacktothebroaden-and-buildtheory

(Fredrickson,1998,2013b),totheextentthatpositivityresonancebuilds

consequentialpersonalandsocialresources,genuineaffiliativesmilesmayhave

evolvedtospurpositivepsychosocialdevelopmentandimprovedphysicalhealthin

individuals,relationships,andindeedwholecommunities.Castingloveasamicro-

momentofpositivityresonance,then,offersadetailedevolutionaryperspectiveon

howgenuinesmilescanseedthelife-enhancingstatesofpositivityresonanceand

thusdogood,bothwithinthebodyandwithinsociety.

Conclusions

Love,definedasmicro-momentsofpositivityresonance,maythusbethe

mostgenerativeandconsequentialofallpositiveemotions.Byvirtueofbeinga

singlestate,distributedacrossandreverberatingbetweentwoormorebrainsand

bodiesatonce,love’sabilitytobroadenmindsetsandbuildresourcesmayhave

substantiallygreaterreach.Love,then,isnotsimplyanotherpositiveemotion.

Rather,it’sthemomentaryphenomenonthroughwhichwefeelandbecomepartof

somethinglargerthanourselves.Meaninginlifemaythusemergenotfromthe

grandandunrealisticutopianidealsof“happily-ever-after”love,butfromwhatart

historianNicholasBourriaud(1998)callsthe“day-to-daymicro-utopias”ofshared

positivity.

Seeingloveaspositivityresonancealsoblurstheboundariesthatsurround

theconceptofemotion.Many,ifnotmost,scientificdescriptionsofemotionslocate

theseaffectivephenomenawithinindividuals,confinedwithinoneperson’smind

andskin.Bycontrast,theconceptofpositivityresonancealignswithperspectives

offeredwithinculturalpsychologythatpositionemotionsasunfoldingbetweenand

amongpeopleastheyinteract(e.g.,Mesquita,2001).Seeingemotionsasproperties

ofindividualsmayindeedbeamyopicby-productoftheWesterntendencyto

perceptuallyextractfocalobjectsfromtheircontextualsurround(e.g.,Masuda&

Nisbett,2001).Bycontrast,positioningloveasadynamicprocessthatunfurls

acrossandunifiestwoormoreinteractingindividualsoffersparsimonytoaccounts

ofthesocialandsocietalfunctionsofpositiveemotions.

Seeingloveaspositivityresonancealsoholdspracticalimplicationsforhow

peoplemightstrengthentheirrelationships,familiesandcommunities.Strivingto

improvethesedirectlycanbeliketellingacompletestranger“trustme”inthe

absenceofanytrustworthyactions.Bycontrast,knowingthatrelationships,

families,andcommunitiesgrowstrongertotheextentthatpositivityresonates

betweenandamongpeoplerevealsthevalueofplanningforandprioritizing

positivity.Creatingactivitiesandsafecontextsthatallowreal-timesensory

connectionandsupporttheemergenceofsharedpositiveemotionsbecomesthe

pathwaytobuildsocialbondsandcommunity.Thisguidancemaybeespecially

valuablewithincontemporaryurbanculturesthatpropelpeopletowardmulti-

taskingandtechnology-mediatedsocialconnections.AsnovelistUrsulaLeGuin

(1971)putit:“Lovedoesn’tjustsitthere,likeastone;ithastobemade,likebread;

remadeallthetime,madenew.”

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1Evenso,scientificinvestigationsoflovehavebeenstifledbycontroversy.Ittookcourageandcreativity,forinstance,forsocialpsychologistsEllenBerscheidandElaineHatfieldtosustaintheirpioneeringeffortstostudyromanticloveinthefaceofwhat’scometobecalled“l’affaireProxmire”(Reis,2012)Thisreferstothe1974debacleinwhichWisconsinSenatorWilliamProxmiresingledoutBerscheidandHatfield’sNSF-sponsoredresearchonloveforhisfirstofmanyGoldenFleeceAwards,bestowedtohighlightwhathedeemedtobeoutrageousandshamefullywastefulusesoffederaltaxdollars.2ForsimplicityI’vedescribelove-the-emotionasapropertyofdyads.Importantly,Iseeitasequallyabletoaccountforcommunalexperiencesofsharedpositivity,orwhatHaidtandcolleaguesrefertoasaninnatehivepsychologywhichperiodicallypropelshumanstolosethemselvesenjoyablyinamuchlargersocialorganism,likethecrowdatafootballgame,musicfestival,orreligiousrevival(Haidt,Seder,&Kesebir,2008).Throughphysicalco-presenceandbehavioralsynchrony,love-the-emotioncanthusalsospreadfromdyadstowholecrowdsorcommunities(e.g.,Fowler&Christakis,2008).