Recent advancement of MRI techniques and development of new methods of image analysis have allowed us to study large neural tracts within the human brain. This is based on the principle of diffusion tensor MRI that is similar to that of diffusion-weighted imaging but takes magnitude and direction of the diffusion of water into account. Using this technique we have been able to define large neural tracts within white matter of the human brain. In our centre, connections of thalamus, internal capsule, corpus callosum, and cerebral peduncle with different regions of cerebral cortex have been defined using Bayesian algorithm for DT-MRI tractography. Results of these studies are consistent with our knowledge of neuroanatomy regarding topography and orientation of fibers within human brain. This provides an exciting new way of exploring human brain particularly in relation to cognitive phenomena. In this talk, I will explain the principle of this method, recent discoveries in our centre and possible application of this method in cognitive neuroscience.