Journal of the Tsuruma Health Science Society Kanazawa University Vol.38（1） Original Article 67 〜 74 2014 The usefulness of the Stroop effect during sorting movements -Aging differences in microslips and Stroop interference rate- KazushiKitayama,KatsuyukiShibata* Abstract Thisstudyaimstoverifythedifferencesintaskexecutionaccordingtooralandmanual classification,thecorrelationbetweenrequiredtimeandthenumberofmicroslips,andthe differenceintheStroopinterferencerateamongyoungpeopleandmiddle-agedpeople. Therewere16targetsinExperiment1（21 to55yearsofage）;andinExperiment2,30 targetsintheyounggroup（ages 20to39）and30inthemiddle-agedgroup（ages 40to59）, allofwhomwerenormal,healthyadults.Weusedfourvarietiesof16classificationcards, andclassifiedeach.InExperiment1,wecalculatedtherequiredtimefortheoralandmanual tasksandtheStroopinterferencerate;andinExperiment2,wecalculatedtherequiredtime duringthemanualtasks,theStroopinterferencerate,andthenumberofmicroslips,and comparedtheoralandmanualtasks,aswellastheyounggroupandthemiddle-agedgroup. TheStroopinterferenceratewassignificantlyhigherduringtheoraltasksthanduringthe manualtasks（p <.05）.Comparingtheyounggrouptothemiddle-agedgroup,themiddle- agedgrouphadasignificantlyhigherStroopinterferencerateinbothoralandmanualtasks thantheyounggroup（p <.05）.Themiddle-agedgroup’snumberofmicroslipsincreased significantlycomparedtotheyounggroup（p<.05）. Asforthecorrelationbetweenthe requiredtimesandthenumberofmicroslips,ahighcorrelationwasshowninthe4varieties ofclassificationcards（p <.05）.Inthisstudy,theStroopinterferencerateonchoicereaction washigherinoraltasksthaninmanualtasks.Furthermore,oralreactiontimeswereslower thanmanualreactiontimesinbothsimpleandchoicereactiontasks.Itwasindicatedthatthe numberofmicroslipsincreaseswiththedelayintime,andacorrelationbetweenthenumber ofmicroslipsandtimewasshown. Key Words Strooptask,Stroopinterferencerate,Microslip,Manualtask,Aging Introduction functionishelpfulinevaluatingtheirbasicandapplied Weareexposedtovarioustypesofinformationfrom movements.Amongtheexecutivefunctiontests,the ourperipheralenvironment,andweactwhileselecting WisconsinCardSortingTest（WCST） isusedinclinical thenecessaryinformation.However,itisdifficultto settings,butifitcanbeadministeredrelativelyeasily processinformationwhilesimultaneouslyselecting asStrooptasks,itmaybegenerallyusefulasaclinical numerouspiecesofinformation1-2）.Executivefunctionhas evaluationtoolfortheelderly.Hasheretal. 6 ） usedthe theabilitytoplan,inhibit,andcontrolattentionandactions3）. WCSTasarestraintfunctionthatcausedtheStroop Inrecentyears,ithasbeenindicatedthatexecutive effect.AcharacteristicoftheStroopeffectisthatthe functiondisorderscontributetoelderlypeople’sfalls outputsuppressesaresponsetoeasystimulus,and andthedeclineinactivitiesofdailyliving（ADL） 4-5）．It theoutputisataskthatrespondstodifficultstimulus. issuggestedthatevaluatingelderlypeople’sexecutive Additionally,theStroopeffecthasastrongcorrelationto KeiaiHospital * SchoolofSciencesCollegeofMedical,PharmaceuticalandhealthSciences,KanazawaUniversity −67− Kazushi Kitayama , et al. theMiniMentalStateExaminationdementiaevaluation7）, werearrangedonawhiteboardinfour-cardcolumnsand andthedecreaseinrestraintfunctioniscausedby four-cardrows.Thecardswere6×6squarecentimeter. cognitivefunctiondecline8-9）．WiththeStroopeffect, 3）ExperimentSetting ratherthanthenamingofcolors,thereadingofthe Thesubjects’measuredposturewasseated（Figure 2）. letters/wordsisfast10）．Generally,aStrooptaskhasoral Handmovementsduringtheexperimentwererecorded responses,andtherequiredtimeshowstherestraint withavideocamera（Canon: iVIHR1）. reactionuntiltheresponse.Thistypeofrestraintreaction 4）Implementation occursnotonlyinoralbutalsoinmanualresponses.In Themethodsinvolvedorallysorting（oral sort）and aclinicalsetting,makingasubjectiveevaluationwhile manuallysorting（manual sort）theclassificationcards. observingapatient’sbehavioriscommon.Itissuggested Theoralsortwas1）WordCards:WordReading,2）Color thatquantitativelyevaluatingnon-fluentmovement Cards:ColorNaming,3）Color-WordCards:ColorNaming, isimportantininvestigatinghindrancesinbehavioral and4）Word-ColorCards:WordReading.Themanual actions. sortwas1）WordCard:SortbyWord,2）ColorCards: Thisstudyfocusedontheusefulnessoftheevaluation SortbyColor,3）Color-WordCards:SortbyColor,and4） oftheStroopeffectduringsortingmovements.Inour Word-ColorCards:SortbyWord.Theinstructionswere dailyactions,themicroslipphenomenonoftenoccurs,such tocallthecolororwordofthecards,orputtheminthe ashesitatingbehavior,thetrajectoryofourmovements, classificationboxesbyhand. andchangesintheshapeofourhands11）.Criteriaof 5）AnalyzingMethod themicroslipsis"Hesitations","TrajectoryChanges", Thetimerequiredfortaskexecutionwasmeasured "HandShapeChanges",and"TouchesandTake/Gives". byastopwatchfromthevideorecordingofthesubjects’ IntheStrooptaskinthisstudy,thedegreeofexecutive vocalizationsandmovements.Themeasurement functionisnotlimitedtorequiredtime.Inthisway,itis wasperformedbytwooccupationaltherapists,who possibletodemonstratemovementpatternsasamicroslip determinedtheaveragerequiredtime. phenomenon. 6）StatisticalProcessing Thegoalsofthisresearchweretoverify 1 ） the TheStroopinterferencerate12）wascalculatedaccording differencesbetweentheoralclassificationandmanual tothecalculationmethodsofHakodaetal（Stroop classification2）,thecorrelationbetweenthetimerequired interferencerate=（（3） requiredtimeofthecolor-word forataskandthenumberofmicroslips,and3）the cards－（2） requiredtimeofcolorcards）/（2）required differencesbetweentheyounggroupandthemiddle-aged timeofthecolorcards ×100）.Thecomparisonof groupinamanualStrooptask. manualsortingandoralsortingwastestedbyatwo-way analysisofvariance.Additionally,toclarifythepresence Methods orabsenceofinteractionbetweenthetwotasks,asa 1. Experiment 1: The differences between oral secondarytest,weperformedmultiplecomparisons, classification and manual classification makingaBonferroniadjustmenttoapairedt-test.For 1）Subjects thecomparisonoftheyounggroupandthemiddle-aged Thesubjectswere16normal,healthyadults（aged 35.5 group,anunpairedt-testwasperformed.Thesignificance ±10.1）.Wereceivedwrittenconsentfromthesubjects, levelswerealllessthan5%. explainingthepurposeofourresearchbothverballyand 2. Experiment 2: Differences among tasks and age inwriting.Ourresearchwascarriedoutwiththeapproval group in manual sorting oftheMedicalEthicsCommitteeofKanazawaUniversity 1）Targets （approvalnumber:353）. Therewere30targetsintheyounggroup（ages 20 2）ClassificationCards to39）and30targetsinthemiddle-agedgroup（ages 40 Theclassificationcardswerecomposedofthefollowing to59）;allsubjectswerenormal,healthyadults,andall fourvarieties:16black-inkwordcards（red: 4;blue:4; wereright-handed.Theaverageageintheyounggroup yellow:4;green:4）,16coloredcolorcards,32incongruent was30.2 ±4.6,andtheaverageageinthemiddle-aged color-wordcards（Figure 1）.Theclassificationcards groupwas49.3±6.0.Wereceivedwrittenconsentfrom −68− The usefulness of the Stroop effect during sorting movements -Aging differences in microslips and Stroop interference rate- Figure 1. Sorting Card The classification cards are composed of the following four varieties: 16 black-ink word cards（red: 4; blue: 4; yellow: 4; green: 4）, 16 colored color cards, 32 incongruent color-word cards. Figure 2. The setting of the experiment design The subjects’ measured posture is seated. Hand movements during the experiment are recorded with a video camera. thesubjects,explainingthepurposeofourresearchboth asasecondarytest,weperformedmultiplecomparisons, verballyandinwriting.Ourresearchwascarriedout makingaBonferroniadjustmenttoapairedt-test.For withtheapprovaloftheMedicalEthicsCommitteeof thecomparisonoftheyounggroupandthemiddle-aged KanazawaUniversity（approval number:353）. group,anunpairedt-testwasperformed.Thesignificance 2）ClassificationCards levelswerealllessthan5%.Forthecorrelationcoefficient Theclassificationcardsarethesameasusedin betweenthetimeandthenumberofmicroslips,Spearman’ Experiment1. srankcorrelationwascalculated.TheStroopinterference 3）ExperimentSettingandMethods rate12）wascalculatedaccordingtothecalculationmethods Theexperimentsettingandmethodsarethesameasin ofHakodaetal.12）. Experiment1（Figure 2）. FromthecalculatedStroopinterferencerate,apaired 4）AnalysisMethods t-testwasperformedcomparingmanualsortingand Theevaluationitemsmeasuredtherequiredtimeand oralsortingtasks,withaBonferroniadjustment.Again, thenumberofmicroslips.Themicroslipcalculationwas forthecomparisonoftheyounggroupandthemiddle- performedbytwooccupationaltherapistsandtheinter- agedgroup,anunpairedt-testwasperformed.The rateragreementwasdeterminedbythekappacoefficient. significancelevelswerealllessthan5%.Thestatistical 5）StatisticalProcessing analysissoftwareSPSS（Version 20）wasusedduringthe Thecomparisonofmanualsortingandoralsortingwas statisticalprocessing. testedbyatwo-wayanalysisofvariance.Toclarifythe presenceorabsenceofinteractionbetweenthetwotasks, −69− Kazushi Kitayama , et al. Table 1. The average of required time for oral sorting and manual intherequiredtimeforwordcardsandcolorcards. sorting However,therequiredtimeforcolor-wordcardsamong oralsorting manualsorting themiddle-agedgroup（28.7 seconds）wassignificantly wordcards 7.7 ± 0.5 21.0± 3.3 colorcards 9.9 ± 0.6 19.2 ± 2.0 slowercomparedtotheyounggroup（23.1 seconds）（p < color-wordcards 15.3 ± 1.4 25.7 ± 6.5 .05）.Intheword-colorcardsasignificantdifferencewas word-colorcards 10.0 ± 0.6 19.7 ± 4.1 （seconds） confirmedbetweenthemiddle-agedgroup（21.4 seconds） In the comparison of time among tasks, the required time for color-word cards