Two-dimensional population map of cortical connections in the human internal capsule

Purpose: To exploit diffusion imaging tractography to produce a two-dimensional (xy) probabilistic population map of the cortical connections within the human internal capsule (IC). Materials and Methods: Diffusion tensor imaging (DTI) was carried out on 11 healthy volunteers. We parceled an axial section of the IC according to its connections to the prefrontal, premotor, primary motor, primary somatosensory, posterior parietal, and occipital cortices using our locally developed probabilistic algorithm. Results: A consistent topographical organization was generated that was consistent with our anatomical knowledge of the IC. In addition, our study shows that in humans the anterior half of the IC is occupied by the prefrontal cortex. Conclusion: This map may be of clinical use for correlating neurological deficit with hemispheric lesions, particularly those that affect sensorimotor function.