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JinFan,Ph.D.??TheSacklerInstituteforDevelopmentalPsychobiologyDepartmentofPsychiatryWeillMedicalCollegeofCornellUniversityATTENTIONANDATTENTIONALNETWORKS???????Whatisattention?Whatisattention?AttentionisrelativelyeasytodefinesubjectivelyasintheclassicaldefinitionofWilliamJameswhosaid:“Everyoneknowswhatattentionis.Itisthetakingpossessionofthemindinclearandvividformofoneoutofwhatseemseveralsimultaneousobjectsortrainsofthought.”(James,1890).However,thissubjectivedefinitiondoesnotprovidehintsthatmightleadtoanunderstandingofattentionaldevelopmentorpathologies.Itisnowpossibletoviewattentionmuchmoreconcretelyasanorgansystem.Wefollowthedictionarydefinitionofanorgansystem(Webster’sdictionary).“Anorgansystemmaybedefinedasdifferentiatedstructuresinanimalsandplantsmadeupofvariouscellandtissuesandadaptedfortheperformanceofsomespecificfunctionandgroupedwithotherstructuresintoasystem”.Webelievesthatviewingattentionasanorgansystemaidsinansweringmanyperplexingissuesraisedincognitivepsychology,psychiatryandneurology.ThreeAttentionalNetworksThreeAttentionalNetworksAlertingAchievingthealertstate:theabilitytoprepareforasensorysignalAttentionalNetworksAttentionalNetworksManypathologiesincludingattentiondeficitdisorder,schizophreniaanddepressionincludeareductionintheefficiencyofattention.Inordertounderstandsomeofthiscommonpathologyitisimportanttoknowthebrainareasinvolvedinattention.OrientingSelectionofinformationfromsensoryinput:turningattentiontowardasensorysignalExecutiveControlResolvingconflictbetweenresponses:selectingonedimensioninthepresenceofcompetinginformationAttentionalNetworksBehavioralStudyGeneticAnalysisfMRIERPPatientstudyComputationalmodelingBehavioralStudyAttentionalNetworkTestnocuecentercuedoublecuespatialcue++CueTarget+*+*+**+100ms400msD=400–1600msRT1700ms3000–RT–Dmsincongruentcongruent+**Neutral++Behavioraldefinitionsoftheefficiencyofattentionalnetworks•ALERTING:RTnocue–RTdoublecue•ORIENTING:RTcentercue-RTspatialcue•CONFLCIT:RTincongruent–RTcongruentResultsResultsAlertingeffect=47msOrientingeffect=51Conflicteffect=84ms400450500550600650neutralcongruentincongruentTargetReactionTime(msec)nocenterdoubleSpatialAlertingAge(yesrs)Alerting(ms)4.09.014.019.024.029.030507090110130150170190OrientingAge(yesrs)Orienting(ms)4.09.014.019.024.029.020304050607080ConflictAge(yesrs)Conflict(ms)4.09.014.019.024.029.05060708090100110OverallRTAge(yesrs)OverallRT(ms)4.09.014.019.024.029.0400500600700800900100011001200130014001500DevelopmentofAttentionalNetworksfMRIandERPstudy:BrainactivationsandthetimecourseExecutiveControlofAttentionExecutiveControlofAttentionThreeConflictTasksThreeConflictTasksFlankertaskColorStrooptaskSpatialconflicttask?cccc706050403020100706050403020100102030FLANKERTASKCOLORSTROOPSPATIALCONFLICTCONJUNCTIONOFTHREETASKScccc706050403020100706050403020100102030FLANKERTASKCOLORSTROOPSPATIALCONFLICTCONJUNCTIONOFTHREETASKS706050403020100706050403020100FLANKERTASKCOLORSTROOPSPATIALCONFLICTCONJUNCTIONOFTHREETASKS706050403020100706050403020100FLANKERTASKCOLORSTROOPSPATIALCONFLICTCONJUNCTIONOFTHREETASKS706050403020100FLANKERTASKCOLORSTROOPSPATIALCONFLICTCONJUNCTIONOFTHREETASKS++Fixation500ms100ms1000–1500ms,randomTargetincongruentcongruent-2000200400600800-2-101234567Time(msec)?Vcongruentcongruenterrorincongruentincongruenterror-2000200400600800-1-0.500.5Time(msec)?Vdifference:incongruent-congruentStimulusonsetImagingAttentionalNetworksImagingAttentionalNetworksWeransubjectsinaneventrelatedfMRIexperimenttofindbrainareasactiveforthethreefunctionsofattention.nocuecentercuespatialcue*++++CueTarget+*+*+*300–11800,Mean:2800ms200ms1700ms3000–15000,Mean:6000msincongruentcongruentAlertingNetworkOrientingNetworkConflictNetworkGeneticanalysisHeritabilityofattentionalnetworksHeritabilityofattentionalnetworksTwinAlertingOrientConflictRTMZ.465*.099.727**.740**DZ.375.395*.281.659**HeritabilityAlertOrientConflictRTh2F=2(rMZ–rDZ).18-.59.89.16h2H=(rMZ–rDZ)/.14-.49.62.24(1–rDZ)MLfit:h2.18.00.72.16c2.28.25.00.58e2.53.74.28.26DRD4exonIII4-repeatalleleinfluenceonconflicteffectP0.00418615N=M104PV4A2.001.00Mean+-1SECONFLICT.19.18.17.16.15.14.134repeatpresent4repeatabsentPatientstudy•ADHD•PatientswithbraindamageComputationalModelingofHumanAttentionalNetworksHongbinWang,Ph.D.CenterforComputationalBiomedicine&SchoolofHealthInformationSciencesUniversityofTexasHealthScienceCenteratHoustonMultilevelModelingofAttentionalNetworks•Developcomputationalmodels,atbothsubsymbolicandsymboliclevels,tosimulatethethreeattentionalnetworksandtheANTresults.•Providecomputationallinksbetweenbiologicalrealityandcognitivebehavior.Subsymbolicmodelinginleabra(PDP++)VisualInputPrimaryVisualCortexObjectPathwayOrientingNetworkAlartingNetworkExecutiveControlNetworkOutputSymbolicmodelinAct-R/PMProceduralMemoryDeclarativeMemoryCurrentGoalConflictResolutionRetrievalResultRetrievalRequestProductionCompilationTransformGoalPoppedGoalSub-symbolicProcessAct-REnvironmentByMichaelI.PosnerCognitiveneuroscienceisboundtoimproveinspatialandtemporalresolutionandinitsabilitytoexamineactiv