Three-dimensional finite-difference EEG forward problem solution on high performance computers

EEG forward problem solution using numerical head models with the same resolution and geometry as that available from MRI is desirable. This implies dealing with realistic head models of over 2 million elements, for which problem solution has so far been impractical due to issues of computation time and memory. This paper investigates the possibilities given by high performance computing (HPC) to obtain efficient EEG forward problem solution with high resolution head models of over 2 million elements at reduced computation time. In this paper, a finite difference forward problem solution based on HPC is proposed and tested with parallel implementations of different complexity. Solution feasibility with different HPC schemes is analyzed to individuate, by cost-effectiveness, the most appropriate system configurations allowing the best performances. Results indicate that a feasible solution based on a cluster of 8 processors is convenient, obtaining computation times not higher than 2 minutes. Increasing the cluster size above 32 processors gives no significant improvement in the computation times.