Neural Systems Affected in Developmental Dyslexia Revealed by Functional Neuroimaging

Table 1Colocalization of Functional Neuroimaging Studies Investigating Differences between Dyslexics and Controls During Phonological and Visual Motion Processing TasksRhyme JudgmentVisual MotionAuthorRumsey et al.Rumsey et al.Rumsey et al.Paulesu et al.Shaywitz et al.Eden et al.Demb et al.(1992)(1997)(1996)(1996)(1998)*(1996)*(1997)*Response typeDecision makingPronunciationDecision makingDecision makingDecision makingNoneNone(button press)(button press)(button press)(button press)#STMRegion (Brodmann area)MTV/V5(19/37) L+50 −70 +05 C--- CR+52 −75 +08 C--- CInferior parietalSupramarginal(39/40) L--- C−28 −32 +44 C−44 −40 +28 C−46 −44 +24 #CR+52 −22 +28 C+40 −62 +28 C+/−47 +/−45 +/−33 CTemporalSuperior temporal(42/22) L−52 −30 +12 C−44 −22 +04 CR+44 −20 −04 C+/−53 +/−43 +/−11 CMedial temporal(21/37) L--- C−54 −22 −04 C−50 −56 +08 CR+46 −58 −08 CInferior temporal/Fusiform L−42 −28 −16 C−48 −40 −16 CR--- C+50 −34 −20 C+48 −30 −20 COccipitalStriate/extrastriate(17/18) L−10 −92 00 D−24 −84 −04 D+/−08 +/−89 +/−03 CR+/−36 +/−80 +/−05 CFunctional brain imaging studies employing PET or fMRI (*) that have identified differences between dyslexics and controls in the posterior areas of the brain during phonological processing or visual motion processing. “C” and “D” denote which of the two groups (controls or dyslexics, respectively) showed greater activation. Talairach coordinates correspond to distance in millimeters from the anterior commissure (+ corresponds to right hemisphere; − corresponds to left hemisphere). Phonological processing studies represent group data and visual motion studies represent single subject data. STM, short-term memory task.

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