A computational platform has been developed that is capable of simulating electromagnetic (EM) field interactions with neurons in complex tissue-structure environments. The platform has been tested in three case studies, namely: a) transcranial alternating current brain stimulation; b) MRI gradient coil switching induced nerve stimulation; and c) muscle activation by a neuroprosthetic implant. These applications were based on the use of a functionalized head and a whole-body model. Additionally a dedicated EM solver coupled with dynamic models of neuronal activity was also implemented. A high-resolution model of the head was developed for the analysis of EM-neuron interactions. Multimodal magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) data were acquired to guide neuron model placement and provide information on tissue anisotropy. The model, called “MIDA”, features a large number of structures, particularly those (ears, eyes, and selected deep brain structures) relevant for applications such as DBS (Deep Brain Stimulation) and neuroprosthetics. A DBS application example is also shown.