Table 1.

Primary speech characteristics associated with primary progressive apraxia of speech (PPAOS) and progressive apraxia of speech (PAOS); listed in order from most to least prevalent among patients.

PPAOS (Josephs et al., 2012, N=12)*	PAOS (Duffy, 2006, N=80)**
Slow rate	Slow rate
Lengthened intersegment durations	Distorted substitutions
Increased distortions and distorted substitutions with increased length or complexity	Syllable segmentation/excess & equal stress
Syllable segmentation within words > 1 syllable	Poorly sequenced SMRs
Sound distortions	Increased errors with increased utterance length
Syllable segmentation across words in phrases	Sound sequencing errors
Audible or visible articulatory groping	Articulatory groping/false starts
Lengthened vowel &/or consonant segments	Distorted additions
Distorted substitutions	Reduced words per breath group in spite of adequate maximum vowel duration
Deliberate, slowly sequenced, segmented, &/or distorted SMRs in comparison to AMRs	Effortful orofacial movements during speech
Increased distortions or distorted substitutions with increased rate	Inaccurate speech AMRs
Distorted sound additions	Sound prolongations
Sound/syllable repetitions
Sound prolongations (beyond lengthened segments)
Inaccurate place or manner of speech AMRs
Reduced words per breath group relative to maximum vowel prolongation

^*The first five features were present in all patients.

^**The first six features were present in 50-85% of patients. Eleven percent of patients in this cohort probably had PPAOS.