This paper presents the use of diffusion tensor magnetic resonance tractography to visualize the three-dimensional (3D) structure of major white matter fasciculi in the human brain. The authors applied this technique to visualize nine specific fasciculi: superior longitudinal (arcuate), inferior longitudinal, superior fronto-occipital (subcallosal), inferior fronto-occipital, uncinate, cingulum, anterior commissure, corpus callosum, internal capsule, and fornix. The fasciculi were isolated and interactively displayed as 3D-rendered objects, providing a "virtual in vivo interactive dissection" (VIVID) that closely matches classical neuroanatomical descriptions. The study utilized diffusion tensor MRI (DT-MRI) to estimate the self-diffusion tensor in each voxel, which was then used to reconstruct the 3D trajectories of the fasciculi. The results were compared with classical neuroanatomy studies and found to be faithful, demonstrating the potential of DT-MRI in visualizing white matter anatomy in living human subjects. The technique is noninvasive, quick (14 minutes), and has clinical applications due to its ability to acquire data in a short time. The authors also discuss the limitations of the method, such as the averaging of fiber orientations within voxels and the impact of noise, and suggest future improvements, including the use of improved imaging hardware and more accurate tracking algorithms.This paper presents the use of diffusion tensor magnetic resonance tractography to visualize the three-dimensional (3D) structure of major white matter fasciculi in the human brain. The authors applied this technique to visualize nine specific fasciculi: superior longitudinal (arcuate), inferior longitudinal, superior fronto-occipital (subcallosal), inferior fronto-occipital, uncinate, cingulum, anterior commissure, corpus callosum, internal capsule, and fornix. The fasciculi were isolated and interactively displayed as 3D-rendered objects, providing a "virtual in vivo interactive dissection" (VIVID) that closely matches classical neuroanatomical descriptions. The study utilized diffusion tensor MRI (DT-MRI) to estimate the self-diffusion tensor in each voxel, which was then used to reconstruct the 3D trajectories of the fasciculi. The results were compared with classical neuroanatomy studies and found to be faithful, demonstrating the potential of DT-MRI in visualizing white matter anatomy in living human subjects. The technique is noninvasive, quick (14 minutes), and has clinical applications due to its ability to acquire data in a short time. The authors also discuss the limitations of the method, such as the averaging of fiber orientations within voxels and the impact of noise, and suggest future improvements, including the use of improved imaging hardware and more accurate tracking algorithms.