The brain shifts following the implantation of intracranial electrodes used to monitor and map brain activity prior to epilepsy resection surgery. Evaluating the factors that contribute to the shift will help improve interpretation of the data monitored. Specifically, the researchers evaluated the effect age and brain volume have on the amount of post-surgical brain shift. They have developed the image processing and analysis tools to evaluate the shift and its relation to other factors. They are analyzing data to assess factors affecting brain shift and are continuing to expand analysis to evaluate the effect of brain areas on the shift.