Frontotemporal Dementia Symptoms & Causes and How it Differs from Other Dementias

Last Updated: August 28, 2018


Frontotemporal dementia (FTD) is the name given to a group of dementias that primarily affect an individual’s personality / behavior, language / speech, or movement. This disease is caused by nerve cell damage in the frontal and temporal lobes within the brain. (The frontal lobes are behind one’s forehead and the temporal lobes are behind one’s ears). As the brain cells are damaged and die, the lobe areas shrink. FTD is progressive, meaning that over time, the symptoms worsen. Diseases in this group include the following:

  • Pick’s Disease
  • Frontotemporal Lobar Degeneration (FTLD)
  • Behavior Variant Frontotemporal Dementia (bvFTD) – problems with behavior, personality,
  • judgment, and emotions
  • Primary Progressive Aphasia (PPA) – problems speaking
  • Semantic Variant PPA (svPPA) – problems understanding language
  • Corticobasal Syndrome (CBS) – problems with movement

According to The Association for Frontotemporal Degeneration, frontotemporal dementia is the most common type of dementia for individuals under 60 years of age. It is estimated that approximately 50,000 – 60,000 Americans have this type of dementia.


How Frontotemporal Dementia Differs From Other Dementias

Unlike most other forms of dementia, memory is not affected in people with frontotemporal dementia until later in the disease. FTD mainly affects different parts of the brain than are affected by other forms of dementia: the frontal and temporal lobes. Also, this form of dementia strikes people at a relatively younger age — usually between the ages of 45 and 65. However, FTD can affect individuals both younger and older than this range.


Causes of FTD

Causes and risk factors of frontotemporal dementia are somewhat different from other forms of dementia. While the exact cause of the damage is unknown, some cases are due to a genetic mutation. More specifically, in these individuals the onset of FTD seems to occur as a result of mutations concerning the so-called Tau gene and the proteins it helps produce. These abnormal proteins accumulate in the brain and can form Pick bodies, which are named after Dr. Arnold Pick, who first identified them. These proteins and Pick bodies disrupt brain cell function in similar ways to the plaques and tangles found in Alzheimer’s disease and the Lewy bodies found in Lewy body dementia. However, as mentioned previously, unlike Alzheimer’s disease and Lewy body dementia, frontotemporal dementia mainly affects the frontal and temporal lobes of the brain. These areas are the centers for thought, speech, and behavior.

Approximately half of all individuals with frontotemporal dementia have some family history of FTD or another dementia. Frontotemporal dementia affects men and women about equally.


Symptoms of FTD

As with causes, symptoms of FTD are also somewhat different from other forms of dementia. The main symptoms of frontotemporal dementia are changes in personality and loss of the ability to express and understand language, or difficulty with movement. Unlike Alzheimer’s disease and Lewy body dementia, FTD does not generally affect an individual’s memory until the more advanced stage.

Changes in Personality / Behavior

FTD affects the front, right side of the brain, which controls our behavior, judgment, personality, and ability to manage complex tasks. Individuals with this form of dementia might look like they are “acting up” because they may start behaving oddly or inappropriately in public places or around strangers. Examples include shoplifting, encroaching on someone’s personal space, and inappropriate sexual behavior. Social skills like tact and empathy may be lost. They may lose interest in everything, or they may suddenly need to be active all the time. They often lose the ability to make informed and safe decisions about tasks, such as managing finances or driving in the car. When the behavioral problems are the most obvious, this form of dementia may look a little like depression, schizophrenia, or bipolar disorder. Not all people with FTD will show all of these symptoms.

Changes in Speech / Language

This disease also affects the way in which an individual is able to use and understand language. One may hear FTD called by the names “semantic dementia” and “primary progressive aphasia.” Both of these names refer to a particular set of symptoms that affect language in frontotemporal dementia:

1) Semantic dementia: Semantic dementia refers to the disease’s effect on the temporal lobes of both sides of the brain. This region of the brain controls how we understand and recognize words, faces, and their meaning. A person with this symptom of FTD would have trouble communicating, both using words correctly and understanding what is being said. Difficulty with reading and spelling is also seen with semantic dementia.

2) Primary progressive aphasia: PPA refers to the disease’s effect on the left side of the brain. This region of the brain controls the way in which we are able to put words together and express meaning. Individuals may have trouble finding and using the right words to explain themselves and they may have trouble forming a structured sentence.

Changes in Movement

Muscle weakness and issues with coordination, such as shaky limbs, trouble with walking, and recurrent falls, may also be a symptom of FTD. In fact, movement problems might become so severe the individual inflicted with the disease may require a wheelchair or be bedridden. Other issues might include difficulty with chewing, swallowing, incontinence (lack of ability to control urination and / or defecation). Note: Some of these symptoms are similar to that of Parkinson’s disease dementia.


Diagnosis and Treatment of FTD

While there currently are no treatments specifically for FTD, approaches to diagnosis and treatment of frontotemporal dementia are similar to other forms of dementia. Follow the links below to learn more:

Diagnosing Dementia

Treating Dementia


Suggestions for Caregivers

Frontotemporal dementia can be especially difficult for caregivers to deal with because, unlike other forms of dementia, it can affect younger individuals who are still working or who have children in the home. This disease can affect decision-making abilities early on, so it is important to begin making financial and legal decisions soon after the disease starts. In addition to setting up a Durable Power of Attorney, caregivers should also consider having a driving evaluation for their loved ones, before driving becomes a problem.

Care partners should encourage their loved ones to participate in support groups for individuals with frontotemporal dementia, whether online or in person. These interactions can be an important way to deal with a disease that other people often do not understand.

For other recommendations on caregiving, click here.