ABSTRACT
Objective To explore the differences of macrostructural and microstructural and their correlations in brain white matter (WM) between left-and right-handed adults.Methods Structural magnetic resonance imaging (sMRI) and diffusion tensor imaging (DTI) were performed on twenty-three left-handed (LH) and thirty-two right-handed (RH) healthy subjects.The WM volume,fractional anisotropy (FA) and mean diffusivity (MD) were mearsured and compared between the two groups by using the voxel-based morphometry (VBM) and voxel-based analysis (VBA) methods.Results (1) LH adults showed lower WM volume than RH adults in bilateral splenium of corpus callosum (SC) (Left:x=-15,y=-57,z =13.5,t=-5.160;Right:x=18,y=-42,z=12,t=-3.654;P＜0.001).Compared with the RH adults,the FA values in WM of the left postcentral gyrus (PoCG) (x =-24,y =-46,z =54) and the above left insula (INS) (x =-36,y =-12,z =20) increased (P＜ 0.001),as well as the average FA values,the average length and number of streamlines in WM tracts increased (P＜0.05) in LH adults.Compared with the RH adults,the MD values in the right HIP (x=24,y=-34,z=-2) decreased(P＜0.001),as well as the average MD values decreased,and the average length in WM tracts increased (P＜0.05) in LH adults.(2)There was positive correlation between FA and the volume of right splenium of corpus callosum in LH and RH adults (LH:r=0.716,RH:r=0.471,P＜0.05).There was negative correlation between FA and MD in the left PoCG (LH:r=-0.769,RH:r=-0.841),left INS (LH:r=-0.775,RH:r=-0.744) and right HIP (LH:r=-0.842,RH:r=-0.742) in LH and RH adults (all P＜0.05).Conclusion There are differences in both macrostructure and microstructure of white matter in several brain regions and WM tracts between left-handed and right-handed people,and correlations between these measures were also observed.