Two progressively degenerative diseases, amyotrophic lateral sclerosis (ALS, commonly known as Lou Gehrig’s disease) and frontotemporal dementia (FTD, recently in the news with the diagnoses of actor Bruce Willis and talk show host Wendy Williams), are linked by more than the fact that they both damage nerve cells critical to normal functioning—the former affecting nerves in the brain and spinal cord leading to loss of movement, the latter eroding the brain regions controlling personality, behavior and language.