About 15% of human prion disease cases are inherited and are caused mutations in the prion protein. The most common mutation is the E200K substitution causing Creutzfeldt-Jakob disease (CJD), which typically causes rapid onset of dementia and death by age 60. The goal of this project is to understand how the E200K mutation impairs normal brain function and when/how this changes during disease progression. To do this, we will be examining neurons derived from human patients carrying the E200K mutation and comparing them to those without the mutation. We expect to identify observable differences which could in the future be used to identify therapeutic targets which can revert these traits.