Steering the Volume of Tissue Activated With a Directional Deep Brain Stimulation Lead in the Globus Pallidus Pars Interna: A Modeling Study With Heterogeneous Tissue Properties. - Simeng Zhang; Michele Tagliati; Nader Pouratian; Binith Cheeran; Erika Ross; Erlick Pereira (Frontiers Comput. Neurosci., 2020)