The purpose of this study is to identify and distinguish two different types of Progressive Apraxia of Speech through clinical imaging and testing.
All enrolled patients must be over the age of 18, speak English as their primary language, and have an informant who can provide an independent evaluation of functioning.
Each new patient must present with a chief complaint of progressive impairment of speech and must have evidence of AOS documented by a speech-language pathologist during routine clinical evaluation.
At study entry, all patients must have speech sufficiently intelligible for a confident diagnosis of AOS, dysarthria, and/or aphasia, and for acoustic analysis.
Any patient whose speech is not intelligible enough for confident speech-language diagnosis will be excluded from the study.
All patients with concurrent illnesses that could account for speech deficits (e.g., traumatic brain injury, strokes, developmental syndromes), and patients meeting criteria for another neurodegenerative disease (e.g., Alzheimer's type dementia57), will be excluded.
Patients with aphasia or dysarthria who do not have PAOS, or whose aphasia or dysarthria at study entry is more severe than PAOS, will be excluded.
All women who are pregnant, or post-partum and breast-feeding, will be excluded as they are unable to undergo the required imaging. All women who can become pregnant must have a pregnancy test no more than 48 hours before the DaTscan.