Table 1.

Clinical characteristics of PPA and PPAOS

		naPPA	svPPA	lvPPA	PPAOS
Clinical features	Agrammatism	+	−	−	−
	Apraxia of speech	+	−	−	+
	Impaired comprehension	+ (syntactically complex sentences)	+ (single words)	+/−	−
	Impaired naming	−	+	+/−	−
	Impaired object knowledge	−	+	−	−
	Paraphasia	+	+/−	+	−
	Speech rate	Significantly reduced	Normal	Moderately reduced	Significantly reduced
	Impaired repetition	+ (single words)	−	+ (sentences and phrases)	+ (single words)
	Other		Surface dyslexia or dysgraphia

Abbreviations: naPPA=non-fluent/agrammatic variant of primary progressive aphasia; svPPA = semantic variant of primary progressive aphasia; lvPPA = logopenic variant of primary progressive aphasia; PPAOS = primary progressive apraxia of speech