Mean (+SE) percent correct sentence comprehension performance. Notes: (1) (A) Percentage of correct control, cleft, and centre-embedded sentences by diagnosis. (B) Percentage of correct short and long sentences by diagnosis. (C) Percentage of correct subject- and object-relative sentences by diagnosis. For these graphs, error bars represent the SE of the mean. (2) * denotes a significant difference in mean scores (see text for details). In (A), cleft and centre-embedded differences are not shown. (3) NCs, normal controls; naPPA, non-fluent/agrammatic primary progressive aphasia (PPA); lvPPA, logopenic variant PPA; svPPA, semantic variant PPA; bvFTD, behavioural variant frontotemporal degeneration.