1. A brain function data analysis method, comprising: constituting an evaluation value of a connection degree between adjacent voxels based on diffusion tensor data capable of specifying a degree of diffusion of protons within the brain acquired on a voxel-by-voxel basis; analyzing brain function data capable of specifying activated brain regions acquired on the voxel-by-voxel basis, based on the evaluation value of the connection degree between the adjacent voxels.