The role of polysemy in masked semantic and translation prim(17)

M.Finkbeineretal./JournalofMemoryandLanguage51(2004)1–2217

alargenumberofneighbors,oneofwhichwasananimal(e.g.,goan)tooknolongerthannon-wordswhichalsohadananimalneighbor,butveryfewotherneighbors(e.g.,cadel).Thepuzzlehereistoexplainhowtheexis-tenceofananimalneighborcouldbedetectedwithoutapplyingsomekindofsemantictesttoeachneighbor.Somehowthecategory-irrelevantneighborswere lteredout,leavingjustthecategory-relevantneighbor.Weproposethatasimilarmechanismoperatesinsense-se-lection;category-irrelevantsensesareautomatically l-teredout,leavingjustthecategory-relevantsense.

Althoughweprefertheexplanationprovidedbythe lterhypothesis,thereareotherinterpretationsthatneedtobeconsidered.AccordingtotheSenseModel,thelocusofthepriminge ectisatthelevelofdecisionmaking.Whenthesemanticsenseofthetargetresponsiblefortriggeringasemanticjudgmenthasalreadybeenactivatedbytheprime,lesstimeisneededtogenerateadecision,leadingtoasavings(orpriming)e ect.Accordingtothisaccount,then,thecriticalstageintheprocessoccurswellaftertheform-levelpropertiesofthetargethavebeensuccessfullyretrieved.Butthisisclearlynottheonlypointintheoverallprocessatwhichasavingscouldoccur.Forexample,primingmaybeattributedtofacilitationintheinitialstageofwordformrecognition.Alternatively,itmaybethatthecriticalstageintheprimingprocessin-volvesadegreeofsimilarityinthecategorizationpro-cessesofboththeprimeandtarget.Belowweconsiderthesealternativesinmoredetail.

The rstalternativeexplanationsuggeststhatwhatisprimedinthesemanticcategorizationtaskisnotase-manticsense,butrather,theform-levelpropertiesofthetarget.Accordingtothisaccount,primingoccurswhentheprocessesinvolvedininterpretingtheprimealterthestateofthelexicalentryforthetarget,sothatthetar-getÕswordformisrecognizedmorerapidly.Inorderforthistooccur,atop-downprocessisnecessary,whereactivation owsfromthesemanticlevelbackdowntotheformlevel(e.g.,Besner&Smith,1992).Thisaccountessentiallyassumesthatprimingisaperceptuale ect,i.e.,thatasemanticallyrelatedprimefacilitatesrecog-nitionofthetargetÕsform.However,ifthiswerethecase,thenitwouldbedi culttoexplainwhythereisnoL2–L1priminginlexicaldecision,butthereisinse-manticcategorization.Fasterperceptionofthetargetshouldleadtofasterresponses,whateverthetask.

Anotherpossibleexplanationisthatwhatgetsprimedisthecategorizationprocessitself.Forexample,itmightbethatacategorizationprocessisinitiatedfortheprimeaswellasthetarget.Whenthetargetissemanticallyverysimilartotheprime,itmaymeanthatlesse ortisinvolvedinreachingadecisionconcerningthetarget.So,inthecaseofanitemsuchas‘‘whale–DOLPHIN,’’itcouldbethathavingjustcomputedthemeaningof‘‘whale,’’andclas-sifyingitasananimal,itismucheasiertodecidethat‘‘dolphin’’mustalsobeananimal,becausetheprocesses

involvedinclassifyingthesewordsareverysimilar.Thisanalysisisdi erentfromthesuggestionthatprimingisthesimpleconsequenceofasequenceoftwoYES–YESre-sponses(i.e.,acongruencee ect),onetotheprimeandonetothetarget,and,hence,couldaccountforthe nd-ingspresentedinExperiment6,wherewefoundrobustprimingfor‘‘wrist–HAND’’(thecategorybeingBodyPart)evenwhenthecontrolprimewouldalsohaveledtoaYESresponse(‘‘kidney–HAND’’).Accordingtothisanalysis,primingisobservedinthe‘‘wrist–HAND’’(orL2–L1translation)conditionbecausenearidentityofreferenceofthewordspermitsfastersemanticcategori-zation.Thiswouldnotbetrueforthewords‘‘kidney–HAND’’inthecontrolcondition.Inessence,whenboththeprimeandtargetsharemanyofthesameconceptualfeatures,classifyingthetargetisgoingtobefaster.Theappropriateanalogyhereiswithasyllogismoftheform‘‘IfXisamemberofacategory,andYisverysimilartoX,thenitislikelythatYwillalsobeamember.’’Arguably,thesimilarityofreferenceisnotrelevantinlexicaldecisionbecausewhatiscriticalinthattaskiswhetherthestimulusisacorrectlyspelledword.This,then,capturesanim-portantaspectofthetaskdi erencethatweobservedbetweensemanticcategorizationandlexicaldecision.Butthereisalsogoodreasontoquestionthisanalysis.Ifthesimilarityinthecategorizationprocessbetweenprimeandtargetisthesourceofatimesavingsforexemplars,itshouldalsoleadtoasavingsfornon-exemplars.6But,aswesawinExperiment3,thiswasnotthecase.Translationprimingonlyoccurredforexemplars.Also,thisanalysismaybetoostronginitssuggestionthatthesimilarityofreferenceisnotrelevantinlexicaldecisionbecauseweknowthatmaskedL1–L2translationprimingoccursinlexicaldecision(seealsoExperiment4a).

Asnotedearlier,thereisanothertaskthatyieldsL2–L1priming,namelyepisodicrecognition(Jiang&For-ster,2001).Inthisstudy,thereweretwophasestotheexperiment.Inthe rstphase,participantswereaskedtostudyalistofL1words.Inthesecondphase,ingthisspeeded‘‘old–new’’task,JiangandForster(2001)reportedsigni cantmaskedtranslationpriminge ectsintheL2–L1directionforold,butnotnew,targets.Howcanthise ectbereconciledwiththeSenseModelaccounto eredhere?Inanold–newtask,theresponseisclearlydeterminedbywhethertheL1targetstimulusmatchestheepisodicre-cordoftheearlierpresentationofthesameword.Sincesemanticfactorswillberelevantintheencodingofthe

6

Thisdependsonthesyllogism.Suchapredictionisvalidifitisoftheform‘‘IfXisnotamemberofcategory,thenitislikelythatYisalsonotamember,ifXandYareverysimilarobjects.’’