Aphasia is FRONTOTEMPORAL DEMENTIA
Definition and symptoms:
Frontotemporal dementia is a progressive neurodegenerative disorder with three common clinical presentations and at least four different patterns of pathology (Kipps & Hodges, 2007). The three common clinical presentations are:
- Behavioral or frontal variant frontotemporal dementia (often abbreviated to bv-FTD or fv-FTD)
- Semantic dementia or temporal variant frontotemporal dementia (often abbreviated to SD or tv-FTD
- Progressive non-fluent aphasia (often abbreviated to PNFA).
The term primary progressive aphasia (often abbreviated to PPA) can be used for both patients who present with semantic dementia and those who present with progressive non-fluent aphasia. Frontotemporal dementia is found in 5-10% of cases of dementia. Frontotemporal dementia tends to affect younger individuals, with approximately three-quarters of the cases presenting from ages 45 to 65, and the remaining quarter presenting after age 65. Up to 10% of patients with motor neuron disease (amyotrophic lateral sclerosis or ALS) also show signs and symptoms of frontotemporal dementia.
Up to 40% of cases of frontotemporal dementia are familial with an autosomal dominant pattern. A small percentage have a mutated tau gene on chromosome 17. In behavioral variant frontotemporal dementia there are changes in personality and social conduct, including apathy, loss of insight, disinhibition, lack of empathy, inappropriate social remarks, abnormal eating behaviors, and neglect of self-care. In semantic dementia there is a loss of memory for words, starting with anomia, continuing with impaired comprehension of words, and ultimately leading to impaired comprehension of objects as well. In progressive non-fluent aphasia there is a reduction in the ability to produce speech characterized by word-finding difficulty, speaking in short sentences, reduced phrase length, and difficulty pronouncing words, similar to that of a patient with Broca’s aphasia.
Although brief cognitive measures such as the Mini-Mental State Examination (MMSE) are sometimes normal in all presentations of frontotemporal dementia, neuropsychological testing will often show dysfunction of tests of attention, response inhibition, frontal/ executive function, and language.