Frontotemporal dementia is relatively rare, accounting for less than 2% of all cases of dementia in the UK. Unlike Alzheimer’s disease, which becomes more likely with increasing age, frontotemporal dementia is less common in individuals over the age of 65, and tends to affect adults between the age of 45 and 65.
A number of different changes have been identified in the brains of individuals with frontotemporal dementia, including abnormal deposits of protein disrupting the function of brain cells and cellular changes similar to those seen in Motor Neurone disease.
These changes affect the frontal (areas behind your forehead) and temporal (areas behind your ears) regions of the brain. The frontal area of the brain supports speaking, planning and controlling behaviour. Whereas the temporal lobes are responsible for comprehending speech, storing factual information and memory.
There are 3 main types of frontotemporal dementia:
- Behavioural: Characterised by a change in personality and behaviour. Symptoms can include a loss of inhibition, reduced empathy, problems planning and organising activities, becoming easily distracted, changes in food preference and a tendency to develop rituals.
- Progressive non-fluent aphasia: Typically causes problems with speech production, for example someone might struggle to find the correct words, pronounce words or use appropriate grammar when speaking.
- Semantic dementia: Affects memories about factual information, such as the knowledge that apples are a fruit. Individuals may have difficulty understanding the meaning of written and spoken language, pictures and objects. In some cases of semantic dementia, a mild form of the behavioural changes may develop as the condition progresses.