Frontotemporal dementia (FTD) is an uncommon type of dementia that causes problems with behavior and language. It is an umbrella term for a group of brain disorders that primarily affect the frontal and temporal lobes of the brain. These areas of the brain are generally associated with personality, behavior, and language. In FTD, portions of these lobes shrink (atrophy), and signs and symptoms vary depending on which part of the brain is affected. Some people with FTD have dramatic changes in their personalities and become socially inappropriate, impulsive, or emotionally indifferent, while others lose the ability to use language properly. FTD tends to occur at a younger age than Alzheimers disease, and most cases are diagnosed in people aged 45-65, although it can also affect younger or older people. The diagnosis of FTD is based on expert evaluation by a doctor who is familiar with these disorders, and brain scans such as magnetic resonance imaging (MRI) and glucose positron emission scans are very helpful additional tests. There are no specific treatments for any of the frontotemporal subtypes, but medications can reduce agitation, irritability, and/or depression.