Figure 7.

Maps of mean curvature of the grey–white matter boundary of the prefrontal cortex (left) for infant c scanned at 31 weeks (A) and 42 weeks (B) EGA. Positive values (red/yellow) represent gyri (convex structures) and negative values (blue) represent sulci (concave structures). The Joint‐Spectral Matching correspondence allows us to map mean curvatures from 42 week to 31 week space (C) and compute the changes in mean curvature between these two time points in 31 weeks space (D). The difference map of the mean curvature over the preterm period indicates the further development of several primary gyri and sulci, like the middle frontal gyrus (indicated by the black arrow), as well as regions where secondary and tertiary sulci will emerge (black square).