Thirty-seven consecutive patients fulfilling consensus criteria for a syndrome of FTD51,52 (19 with bvFTD, nine with svPPA, nine with nfvPPA) and 21 healthy older individuals with no history of neurological or psychiatric illness participated. General characteristics of the participant groups are summarised in Table 1. No participant had a history of facial palsy or clinically significant visual loss after appropriate correction. There was clinical evidence of orofacial apraxia in seven patients in the nfvPPA group, but none in any of the other participant groups. General neuropsychological assessment (see Table 1) and brain MRI corroborated the syndromic diagnosis in all patients; no participant had radiological evidence of significant cerebrovascular damage. Based on visual inspection of individual brain MR images, six patients with a behavioural syndrome and relatively selective right temporal lobe atrophy were re-categorised as a rtvFTD subgroup (throughout this paper, we use ‘bvFTD’ to refer to those patients with a behavioural presentation not re-classified as rtvFTD). Between group differences in demographic and neuropsychological variables were analysed using ANOVAs with post hoc T-tests when main effects were found, except for categorical variables, for which a chi-squared test was used.Table 1Demographic, clinical and neuropsychological characteristics of participant groups.CharacteristicControlsbvFTDrtvFTDsvPPAnfvPPADemographic/clinicalNo. (male:female)9:1210:36:0a7:24:5Age (years)69.1 (5.3)66.2 (6.3)63.8 (6.4)66.1 (6.5)69.6 (6.5)Handedness (R:L)20:112:16:08:17:2Education (years)15.7 (3.5)13.2c (2.5)18.0 (3.1)14.9 (2.8)15.0 (2.1)MMSE (/30)29.6 (0.6)24.5a (4.6)25.3a (4.3)21.8a (6.9)23.7a (6.0)Symptom duration (years)N/A7.7 (6.0)6.5 (3.5)5.6 (3.0)4.7 (2.2)Neuropsychological General intellect WASI Verbal IQ125 (6.7)89a (21.9)87a (22.2)77a (19.7)80a (17.3)WASI Performance IQ125 (10.2)104a (20.3)107 (24.6)108 (23.5)99a (21.5) Episodic memory RMT words (/50)49.0 (1.4)37.4a (7.9)37.2a (9.3)30.0a,c (6.3)41.4a (9.5)RMT faces (/50)44.7 (3.5)33.5a (6.9)34.8a (7.9)32.8a (6.9)39.5 (6.6)Camden PAL (/24)20.4 (3.3)10.8a (8.1)12.5a (6.2)2.2a,b,c,e (3.7)16.3 (7.8) Executive skills WASI Block Design (/71)44.8 (10.5)32.5 (16.7)37.2 (22.1)39.1 (21.7)25.1a (19.7)WASI Matrices (/32)26.6 (3.9)19.3a (9.4)19.0a (9.8)19.8a (10.6)17.4a (9.0)WMS-R DS forward (max)7.1 (1.1)6.6 (1.2)6.8 (1.2)6.7 (1.2)4.8a,b,c,d (0.8)WMS-R DS reverse (max)5.6 (1.2)4.0a (1.5)4.7 (1.4)5.3 (1.8)3.0a, d (0.7)D-KEFS Stroop:color (s)33.4 (7.2)48.0 (20.5)48.8 (21.4)53.2a (28.2)87.0a,b,c,d (6.7)word (s)23.9 (5.6)32.5 (19.0)38.7 (26.1)36.0 (24.0)85.4a,b,c,d (10.3)interference (s)57.6 (16.7)99.6a (47.5)98.3 (45.1)90.1 (56.1)165a,b,c,d (30.8)Fluency:letter (F total)18.1 (5.6)7.8a (4.6)9.0a (4.7)8.9a (7.1)3.5a (1.7)category (animals total)24.4 (6.0)13.8a (7.5)10.3a (2.3)5.7a,b (5.1)8.8a (3.5)Trails A (s)33.7 (7.3)56.5 (32.3)59.8 (32.9)49.7 (20.1)81.7a (48.4)Trails B (s)67.3 (21.5)171.7a (88.2)186.7a (100.4)134.9 (101.7)211.1a (94.6) Language skills WASI Vocabulary72.3 (3.2)42.4a (21.5)47.0a (19.1)33.6a (22.0)31.7a (13.9)BPVS148.6 (1.1)120.8 (38.7)141.8 (7.2)85.8a,b,c,e (53.8)142.6 (10.1)GNT26.1a (2.7)12.2a (10.2)12.5 (10.1)1.6a,b,c,e (4.7)15.5a (6.6) Other skills GDA (/24)15.8 (5.3)7.8a (6.6)7.5a (6.3)11.9 (8.6)5.4a (1.9)VOSP (/20)19.0 (1.5)15.9a (3.4)16.7 (2.3)15.8 (4.5)15.3a (4.7)Mean (standard deviation) scores are shown unless otherwise indicated; maximum scores are shown after tests (in parentheses). asignificantly different from healthy controls, bsignificantly different from bvFTD, csignificantly different from rtvFTD, dsignificantly different from svPPA, esignificantly different from nfvPPA (all p < 0.05). BPVS, British Picture Vocabulary Scale (Dunn LM et al., 1982); bvFTD, patient group with behavioural variant frontotemporal dementia (excluding right temporal cases); Category fluency totals for animal category and letter fluency for the letter F in one minute (Gladsjo et al., 1999); Controls, healthy control group; D-KEFS, Delis Kaplan Executive System (Delis et al., 2001); DS, digit span; GDA, Graded Difficulty Arithmetic (Jackson M and Warrington, 1986); GNT, Graded Naming Test (McKenna and Warrington, 1983); MMSE, Mini-Mental State Examination score (Folstein et al., 1975); N/A, not assessed; NART, National Adult Reading Test (Nelson, 1982); nfvPPA, patient group with nonfluent variant primary progressive aphasia; PAL, Paired Associate Learning test (Warrington, 1996); RMT, Recognition Memory Test (Warrington, 1984); rtvFTD, patient subgroup with right temporal variant frontotemporal dementia; svPPA, patient group with semantic variant primary progressive aphasia; Synonyms, Single Word Comprehension: A Concrete and Abstract Word Synonyms Test (Warrington et al., 1998); Trails-making task based on maximum time achievable 2.5 minutes on task A, 5 minutes on task B (Lezak et al., 2004); VOSP, Visual Object and Spatial Perception Battery – Object Decision test (Warrington and James, 1991); WAIS-R, Wechsler Adult Intelligence Scale‐-Revised (Wechsler, 1981); WASI, Wechsler Abbreviated Scale of Intelligence (Wechsler, 1997); WMS, Wechsler Memory Scale (Wechsler, 1987).