Sulcal/gyral pattern morphology of the perisylvian language region in developmental dyslexia.

Two systems for classification of morphology of the perisylvian cortical area have been suggested, that of Steinmetz et al. (1990) and that of Witelson and Kigar (1992). This study examines whether the variations in placement of these convolutions in the language cortex are related to diagnosis of dyslexia in a clinic-referred sample of 55 children ages 8 to 12 years. Additionally, the systems are compared to determine their relationship to neurolinguistic performance. In this study, the Steinmetz et al. (1990) system captured morphological distinctions which were relevant to performance on neurolinguistic measures, while Witelson and Kigar's (1992) system did not. Under neither system was morphology associated with diagnosis of dyslexia.