The role of polysemy in masked semantic and translation prim(13)

M.Finkbeineretal./JournalofMemoryandLanguage51(2004)1–2213

trialswithvisibleprimeswastoencourageparticipantstocontinuetryingtodothetask.Anacceptableaccu-racyrateonthesetrialsallowsustosafelyassumethatparticipantswereperformingthetasktothebestoftheirabilities.

Resultsanddiscussion

Experiment5a—one-to-manyinsemanticcategorizationThesametrimmingproceduresusedinthepreviousexperimentswereagainemployedhere.InExperiment5a,meanresponsetimesintheone-to-many(or‘‘L2–L1’’)directionwere473msfortargets(e.g.,HEAD)precededbyrelatedone-senseprimes(e.g.,skull)and486msforthesametargetswhenprecededbyacontrolprime(e.g.,shop).AnANOVAshowedthatthisfacili-tatione ectof13mswasreliable(F1ð1;18Þ¼8:15,P¼:01;F2ð1;40Þ¼7:02,P¼:01).Furthermore,justastherewasaninteractionbetweentheresultsofthese-manticcategorizationandlexicaldecisiontasksintranslationpriming(Experiments1and2),sowasthereaninteractionbetweentheresultsofthepresentexper-imentandthoseofExperiment4b(F1ð1;36Þ¼6:54,P¼:01;F2ð1;76Þ¼5:47,P¼:02).Theseresultscon- rmthetaskdi erencebetweensemanticcategorizationandlexicaldecisioninone-to-manypriming.Insodo-ing,these ndingsprovidefurthersupportforthehy-pothesisthatsemanticcategorizationservestorestricttheamountofsemanticinformationrecruitedtogen-erateadecision,therebyenhancingthee ectivenessofthefew-senseprimeword.

Themeanerrorrateinthisexperimentwas5.4%:3.3%onthetrialswithrelatedprimesand7.5%ontrialswithcontrolprimes.Thisdi erencewassigni cantinboththesubjectanditemsanalyses(F1ð1;18Þ¼7:06,P¼:01;F2ð1;40Þ¼7:25,P¼:01),indicatingthatpar-ticipantsbene tedfromarelatedprimeintermsofbothreactiontimesandaccuracy.Theerrorratesconstitutetheonlydi erencebetweenthisexperimentandExper-iment1.InExperiment1,bilingualsdidnotexhibitanydi erenceinerrorratesbetweenconditions.Here,ontheotherhand,thereisthesuggestionthatinformationpresentedintheprimestimuluswasnotonlyactivatingthetargetrepresentation,butalsoenteringintothede-cisionmakingprocess.Althoughitissomewhatunclearhowthiscouldoccur(participantswereunawareoftheprime,seebelow),thepatternoferrorsspeakstothepossibilityofadecisioncon ict.Thatis,participantsmayhavebegungeneratingadecisiononthebasisoftheprimeÕscategorymembership,whichwouldfacilitatedecisionsontheexperimentaltrials,butnotonthecontroltrials.Thisisapossibilitythatweconsiderfur-therinExperiment6.

WithrespecttoparticipantsÕperformanceontheprimeawarenesstask,themaskingprocedureappearstohavebeene ectiveinpreventingawarenessoftheprime.

Ontrialsinwhichthepresentationsequencewasthesameasinthesemanticcategorizationtask,participantscorrectlydetectedprimewordswiththeletter‘‘e’’51.5%ofthetime.Theirperformancedidnotdi erfromchance(F<1).Ontrialsinwhichtheprimewaspre-sentedfor10refreshcycles,participantscorrectlyiden-ti edprimewordswiththeletter‘‘e’’87.8%ofthetime.Takentogether,these ndingsindicate:(1)thatpartici-pantswereperformingthe‘‘e-detection’’tasktothebestoftheirabilitiesand(2)thatonthetrialsinwhichprimedurationmatchedtheprimedurationusedinthese-manticcategorizationtask(41ms),participantsweregenerallynotabletodetecttheprime.Assuch,these ndingsruleoutawarenessasapossiblesourceofthepriminge ectobservedinExperiment5a.

Experiment5b—many-to-oneinsemanticcategorizationAlthoughExperiment5acon rmsthetaskdi erenceintheone-to-manydirection,and,hence,providesstrongsupportfortheassumptionsoftheSenseModel,ouraccountofthetaskdi erencepredictssymmetricalpriminginsemanticcategorization.Forthesakeofcompleteness,then,weconductedExperiment5btocon rmthatmany-to-oneprimingoccursbothinlexicaldecisionandsemanticcategorization.Inthisexperi-ment,meanresponsetimeswere532msfortargets(e.g.,SKULL)precededbyrelatedmany-senseprimes(e.g.,head)and552msforthesametargetswhenprecededbyacontrolprime.This20mse ectwasfoundtobesig-ni cantinboththesubjectanditemsanalyses(F1ð1;18Þ¼7:28,P¼:01;F2ð1;40Þ¼7:67,P¼:008).Importantly,thise ectdoesnotdi erfromthe23mspriminge ectfoundinthemany-to-onedirectioninlexicaldecision(Experiment4a).Again,theseresultscon rmthepredictionsoftheSenseModel.AccordingtotheSenseModel,thereshouldbenotaskdi erencewhentargetshaveveryfewsenses.ThisisbecausetheproportionofthetargetÕssensesactivatedbytheprimewillbeveryhigh,whichwillfacilitatedecisionsinbothlexicaldecisionandsemanticcategorization.Inotherwords,the‘‘focusinge ect’’ofsemanticcategorizationdoesnotprovideanybene twhenthetargethasonlyonesensetobeginwith.

ThemeanerrorrateinExperiment5bwas8.5%.Again,therewasadi erencebetweenexperimentalandcontroltrials.Ontrialsinwhichthetargetwasprecededbyarelatedprime,theerrorratewas6.02%;theerrorrateonthecontroltrialswas10.93%.Thisdi erencewasveryclosetoreachingsigni canceinthesubjectanalysisanddidreachsigni canceintheitemsanalysis(F1ð1;18Þ¼3:82,P¼:07;F2ð1;40Þ¼5:04,P¼:03).Again,thisdi erencesuggeststhatparticipantswereabletobene tfromtheprimebothintermsofreactiontimesandaccuracy.Onepossibleinterpretationis,assuggestedabove,participantswereinitiatingaresponsebasedonthecategorymembershipoftheprime.Ifthis