Investigation of the spatial correlation in human white matter and the influence of age using 3-dimensional variography applied to MP-RAGE data

► Variograms are employed to investigate spatial correlation in MR images. ► Numerical samples provide interpretation of variogram shapes. ► White matter obtained from MP-RAGE data of 24 healthy subjects is analysed. ► White matter is found to have 2 correlation structures, 3 mm and 23 mm in size. ► Inhomogeneity of the 3 mm structure is significantly correlated with age.