Cognitive control of coherent motion perception [Elektronische Ressource] : functional MRI studies of response selection / von Matthias Wittfoth

AusderAbteilungfürNeuropsychologieundVerhaltensneurobiologieZentrumfürKognitionswissenschaften(ZKW)Cognitive Control of coherent motion perception:functional MRI studies of response selectionvorgelegtdemFachbereich2(Biologie/Chemie)UniversitätBremenalsDissertationzurErlangungdesakademischenGradeseinesDoktorsderNaturwissenschaften(Dr.rer.nat.)vonMatthiasWittfothApril2008AbstractExecutive control is a human ability that allows to overcome automatic stimulus-responsemappingsandtoactappropriateinthecontextofataskwheretheselectionofrelevantstimuliandthesuppressionofinterferinginformationarecrucial.Thefirststudy(Chapter2)aimedatcharacterizing the neural correlates of conflict resolution in two variations of the Simoneffect.TwodifferentSimontaskswereintroducedwheresubjectshadtoidentifyshapesonthebasisofform-from-motionperception(FFM)withinarandomlymovingdotfield,while(1) motion direction (motion-based Simon task) or (2) stimulus location (location-basedSimon task) had to be ignored. Behavioral data revealed that both types of Simon tasksinduced highly significant interference effects. Using event-related fMRI we coulddemonstratethatbothtasksshareacommonclusterofactivatedbrainregionsduringconflictresolution (pre-supplementary motor area (pre-SMA), superior parietal lobule (SPL), andcuneus)butalsoshowtask-specificactivationpatterns(leftsuperiortemporalcortex inthemotion-based, and the left fusiform gyrus in the location-based Simon task).