Cortical Complexity Measured via Regional Surface Shape

Background: Few empirical studies have examined individual differences in the frequency of cortical gyrification/fissuration. Existing approaches only provide complexity measures for the whole brain or for specific lobes or brain hemispheres. Here we present a new regional shape measure to evaluate cortical complexity at each point on the cortical surface. Methods: 3D cortical surface models were created from MRI brain scans of 60 healthy adults (30 M/30 F) in ICBM stereotaxic space. To calculate a local measure of surface convolution, a curvature map was computed on each surface: negative maxima correspond to s…