CognitiveTaskOverview: TestMyBrainLetter/NumberSwitchingContact: Info@ManyBrains.netManyBrains.netTestMyBrain.org
TMBTest Name: TestMyBrainLetter/Number SwitchingTest Demo: standardversionDocument Version: May.30.2024
TheManyBrainsProjectTheManyBrainsProject, isa501(c)(3) non-profit that supportsTestMyBrain(TMB) incollaborationwiththeLaboratoryfor BrainandCognitiveHealthTechnologyat McLeanHospital andHarvardMedicalSchool. Wecurrentlysupport manydifferent typesof researchstudiesthroughour infrastructureforcognitiveassessment - theserangeinsizefromsmall lab-basedpilot studiestolargelongitudinal,multisiteclinical researchstudieswithtensof thousandsof participants. AsTestMyBrainhasbeencontinuouslyinoperationsince2008, weprovideastableandsecureplatformfor hostinganddeliveringmobileandweb-basedcognitiveassessment protocols. ThroughTestMyBrain.org, datahavebeencollectedfromover 3.7millionparticipantsinacitizenscienceframeworkthat includesstructuredreturnof researchresultstowardthedevelopment, validation, andnormativecharacterizationof cognitivemeasures. Wecurrentlysupport researchandeducationat over 2,000sitesworldwideengagedindigitalneuropsychological assessment.
CITATIONPleasecredit TheManyBrainsProject andTestMyBraininanypapers, posters, or publicationsrelatedtotheTMBtestsor datacollectedbyTMBtests.● Example:- All taskswereselectedfromandhostedonTheManyBrainsProject’sweb-basedcognitivetestingplatform, TestMyBrain(Germineet al., 2012; TheManyBrainsProject).- Germine, L., Nakayama, K., Duchaine, B. C., Chabris, C. F., Chatterjee, G., &Wilmer, J. B. (2012). IstheWebasgoodasthelab?ComparableperformancefromWebandlabincognitive/perceptual experiments. PsychonomicBulletin&Review, 19(5), 847-857.- TheManyBrainsProject. TestMyBrainCognitiveTests. URL:www.manybrains.net
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Test Overview
Background:TestMyBrainLetter/NumberSwitchingmeasuresresponseselection/inhibition,task-switching,andcognitivecontrol.Thetestwasadaptedfromatask-cuedstimulus-classificationprocedureusedtomeasuretaskswitchingability(Ophiretal.,2009).
TaskParameters:Oneachtrial,eithertheword“LETTER”or“NUMBER”appearedatthetopofthescreenasataskcue.Aftera750msdelay, aletterandanumberweresimultaneouslypresentednexttoeachotherbelowthetaskcue.Thereweresixpossibleoptionsforboththeletter[a,b,c,x,y, z]andthenumber[1,2,3,7,8,9].Atthesametimetheletter-numberpairappeared,tworesponseboxeswerepresentedonthescreenside-by-sidebeneaththeletter-numberpair. Theleftresponseboxcontainedthenumbers“123”andtheletters“ABC,”whereastherightresponseboxcontainedthenumbers“789”andtheletters“XYZ.”Participantswereinstructedtoselecttheleftresponseboxwheneitherthetaskcuewordwas“LETTER”andtheletterintheletter-numberpairwasa,b,orc,orwhenthetaskcuewordwas“NUMBER”andthenumberintheletter-numberpairwas1,2,or3.Participantswereinstructedtoselecttherightresponseboxwheneitherthetaskcuewordwas“LETTER”andtheletterintheletter-numberpairwasx,y, orz,orwhenthetaskcuewordwas“NUMBER”andthenumberintheletter-numberpairwas7,8,or9.Adelayof150msoccurredaftereachtrial.
Aftercompleting10practicetrials,participantscompletedoneunscoredtrial,followedby72testtrials.Eachtrialwasequallylikelytobea“LETTER”or“NUMBER”trial,equallylikelytohavethenumberintheletter-numberpairbeontheleft(e.g.,a1)ortheright(e.g.,1a),andequallylikelytohaveboththeletterandnumberbeconsistentwiththesameresponsebox(e.g.,a1)orwithdifferentresponseboxes(e.g.,a9).
PrimaryOutcome:Thesuggestedprimaryoutcomeofthetestisconflictslowing: howmuchslowerparticipantsarewhentheletterandnumberrequirethedifferentresponses(e.g.,letterleft,numberright)versuswhentheybothrequirethesameresponse.
UserInput:Participantsrespondeitherbytouching(touch-compatibledevices)orclickingtheiranswerselection.
AlternateTaskVersions:Alternateformsofthetestareavailableforrepeatedadministration.
Psychometrics:● Reliability: Insingle-sessiontesting,variationinperformancebetweenparticipantshasasplit-halfreliabilityof.55.● Scoredistribution:
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References:
Ophir, E.,Nass,C.,&Wagner, A.D.(2009).Cognitivecontrolinmediamultitaskers.ProceedingsoftheNationalAcademyofSciences,106(37),15583-15587.
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