Objective    To investigate corticostriatal connections in human brain by diffusion tensor imaging (DTI)

and to define the location of projections from different cortex to striatum with automated probabilistic tractography

in order to provide morphological data for the functional anatomy of human striatum.     Methods    Diffusion weighted images and T

1

images were acquired in 11 healthy volunteers (3.0T Siemens sonata

12 diffusion directions

b=1 000 s/mm

2

36 slices

thickness 3 mm). Image analysi

s used by FDT toolbox of FSL software (www.fmrib.ox.ac.uk/fsl)

different cortex and striatum masks generated by WFU_PickAtlas toolbox in Matlab and SPM (www.fil.ion.ucl.ac.uk/spm)

including frontal

parietal

temporal

occipital

insular lobes

especially motor cortex such as M1

supplement motor area (SMA) and premotor cortex (PMC) were selected. T

1

images were registered to ICBM152-T

1

template

then the diffusion space transferred to the standard space. The striatum masks served as seeds for probabilistic tractography with each target mask

and the striatum seeds were classified according to the target mask with which they showed the highest probability of connection.      Results    The automated parcellation of striatum according to their probability of connections with the different cortical target masks resulted in clearly distinct location in striatum with specific spatial distribution. The frontal projections were located to the head of caudate nucleus and the superior part of putamen

the insular projections to the lateral striatum

the projections from the parietal

temporal and occipital lobes overlapped to the posterior part and the inferior part of striatum. The motor connectivity to striatum was also defined

the M1 projections were connected to the posterosuperior part of striatum

and the SMA projections were connected to the middle part of striatum

the PMC projections were connected to the anterior and posteroinferior parts of striatum.      Conclusion    Human striatum has specific connections with different cortex

and provides the direct demonstration of distinct corticostriatal connections in humans in vivo

which is consistent with previous report. The diffusion tensor imaging is non-invasive method

connectivity-based probabilistic tractography by diffusion images can classify seed voxels according to the target mask with which they show the highest probability of connection

and these differential connections usually are consistent with special function. In conclus

ion

connectivity-based probabilistic tractography and parcellation that is valuable in the functional anatomy of human brain

can identify the different sub-region of human brain structures by virtue of their different probability of anatomical connectivity.