Top part: Mean cortical surface area, cortical thickness in children with PWS and healthy controls in clusters with low lGI. Bottom part: correlations between lGI and cortical surface area/cortical thickness within the clusters in each group and the differences between the groups in their relationships of lGI and cortical surface area/thickness.

Top: Cortical surface area was significantly lower in children with PWS than in healthy controls and no differences were found in cortical thickness. lGI correlated with cortical surface area, but not with cortical thickness in the combined sample. Bottom: lGI correlated with cortical surface area, but not cortical thickness in PWS and healthy controls. No differences between the groups were found in their relationship between lGI and cortical surface area/cortical thickness. LH – Left hemisphere; RH – Right Hemisphere; SD – standard deviation, rho –Spearman's rho.

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Correlations were calculated in total group (PWS + HC)

Top part: Mean cortical surface area, cortical thickness in children with PWS and healthy controls in clusters with low lGI. Bottom part: correlations between lGI and cortical surface area/cortical thickness within the clusters in each group and the differences between the groups in their relationships of lGI and cortical surface area/thickness.