<unk>  <unk>  is a progressive neurodegenerative disorder characterized by loss of<unk>  memory in both the verbal and non-verbal domains. The most common presenting symptoms are in the verbal domain however (with loss of word meaning) and it is therefore often characterized (incorrectly) as a primary language disorder (a so-called progressive fluent aphasia).<unk>  is one of the three canonical clinical syndromes associated with frontotemporal lobar degeneration. <unk>  is a clinically-defined syndrome, but is associated with predominantly temporal lobe atrophy (left greater than right) and hence is sometimes called temporal variant FTLD (tvFTLD).
It was first described by Professor Elizabeth Warrington in 1975 (Warrington EK. The selective impairment of<unk>  memory. Q J Exp Psychol. 1975 Nov;27(4):635-57) but was not given the name<unk>  until 1989 (Snowden JS, Goulding PJ, Neary D.<unk> : a form of circumscribed cerebral atrophy. Behav Neurol 1989;2:167-182.).
Semantic dementia
Multi-infarct dementia
Dementia with Lewy bodies
Early-onset Alzheimer's disease
Multiple system atrophy
Incontinentia pigmenti
Pick's disease
Orientia