Epileptogenic source localization methods and systems based on ECoG signals are provided for obtaining spatial and temporal relationships among epileptogenic zones. Seizure detection is based on an Independent Component Analysis (ICA) and temporal and spatial relationships among the detected epileptogenic zones are based on a steepest descent-based source localization method. Embodiments of the invention facilitate the epileptiform activity investigation and seizure dynamics study and further benefit the neurophysiology community in the surgical decision making of neurosurgeons.