Reading-related functional activity in children with isolated spelling deficits and dyslexia

Figures & data

Figure 1. Competing hypotheses of expected functional activity in the dorsal stream in the two deficit groups compared to typically developing children.

Table 1. Mean scores (M) and standard deviations (SD) for descriptive, literacy, and cognitive measures in the three groups.

	TD		SpD		Dyslexia
	M	SD	M	SD	M	SD	F	p	ES	Post-hoc comparisons
N (males)	22 (11)		16 (10)		20 (13)
Ringht handed	19		14		17
Age (months)	113.36	3.89	115.44	7.51	112.20	4.98	1.59	.214	.06	–
Sentence reading fluency (SLS)^a	54.82	18.86	51.81	14.94	10.30	6.86	57.76	<.001	.68	(TD = SpD) > Dyslexia
Word reading fluency (SLRT-II)^a	48.82	14.01	47.37	20.12	8.80	5.87	51.62	<.001	.65	(TD = SpD) > Dyslexia
Pseudoword reading fluency (SLRT-II)^a	55.32	15.43	54.00	25.21	10.50	7.43	45.35	<.001	.62	(TD = SpD) > Dyslexia
Spelling (DRT-3)^a	51.05	12.57	12.44	4.94	19.70	14.50	60.16	<.001	.69	TD > (Dyslexia = SpD)
Nonverbal IQ	103.59	9.94	100.00	10.11	99.00	10.12	1.21	.307	.04	–
Vocabulary (WISC-IV)^b	11.64	3.35	10.81	3.21	10.90	2.81	.42	.658	.02	–
Digit span (WISC-IV)^b	10.82	3.05	9.50	2.37	11.45	2.74	2.25	.115	.08	–
Symbol search (WISC-IV)^b	11.14	1.75	11.81	2.29	11.35	1.98	.54	.584	.02	–
Phonological awareness^c	.89	.09	.79	.11	.74	.16	7.63	.001	.22	TD > Dyslexia
RAN digits/s^d	1.98	.33	1.86	.43	1.63	.29	5.15	.009	.16	TD > Dyslexia
RAN objects/s^d	1.10	.20	1.09	.17	.94	.12	5.26	.008	.17	(TD = SpD) > Dyslexia
ADHD questionnaire score^e	.34	.30	.74	.41	.64	.46	5.36	.007	.16	TD > SpD

Note. ^aPercentiles; ^bstandard scores; ^craw score calculated as the ratio of correct responses to the total number of responses; ^dRaw score calculated as the number of items named correctly per second; ^ehigher questionnaire scores indicate more ADHD symptoms. Effect sizes (ES) are calculated as partial eta-squared. Post-hoc comparisons are adjusted with Bonferroni correction.

Figure 2. Example of the in-scanner task. Children were instructed to read aloud German words (as for example “Familie” [family]) and pseudohomophones (as for example “Fater”, which sounds as the German word “Vater” [father]).

Table 2. Accuracy in the in-scanner reading aloud task for the three groups, presented separately for each condition.

	TD		SpD		Dyslexia
	M	SD	M	SD	M	SD
Words	59.82	.50	59.56	.63	57.65	2.11
Pseudohomophones	59.32	.95	58.25	1.57	56.05	3.36

Table 3. Results of group comparisons for the condition “words” displayed with FWE correction at the voxel level, p < .05. Clusters ≥ 10 voxels are reported.

				MNI
Comparison	Region	Voxel extent	t	x	y	z
TD > SpD	L Medial Cingulate Cortex	230	7.68	−3	−3	47
	R Posterior-Medial Frontal		10.05	3	−21	70
	L Middle Temporal Gyrus	192	7.44	−57	−6	−15
	L Temporal Pole		11.02	−45	12	−12
	L Fusiform Gyrus	102	7.29	−27	−48	−9
	L Inferior Temporal Gyrus		8.57	−39	−27	−15
	L Lingual Gyrus	50	9.43	−21	−93	−9
	R Postcentral Gyrus	31	8.19	57	−3	37
	L Precentral Gyrus	28	7.64	−54	−3	31
	L Thalamus	23	7.25	−9	−3	−5
	R Middle Temporal Gyrus	23	6.89	51	−24	−5
	L Middle Temporal Gyrus	20	7.03	−66	−36	−9
	L Middle Temporal Gyrus		5.82	−45	−39	−2
	L Precentral Gyrus	16	7.37	−27	−27	67
	R Fusiform Gyrus	15	6.84	45	−75	−12
	L Superior Temporal Gyrus	14	7.19	−45	−36	14
	L Precuneus	13	7.41	−3	−54	11
	R Fusiform Gyrus	11	7.51	39	−27	−15
SpD > TD	R Middle Temporal Gyrus	197	−7.92	66	−39	−2
	R Superior Temporal Gyrus		−7.88	57	−36	18
	R Precentral Gyrus	74	−10.72	45	−12	47
	R Posterior-Medial Frontal	56	−8.76	15	−3	64
	L Rolandic Operculum	46	−8.48	−63	−12	14
	R Superior Frontal Gyrus	41	−8.67	24	18	57
	R Rolandic Operculum	40	−7.08	57	−12	18
	L Lingual Gyrus	38	−11.69	−27	−63	8
	L IFG (Triangularis)	31	−6.99	−48	12	14
	R Lingual Gyrus	23	−6.32	24	−66	8
	L Postcentral Gyrus	19	−7.53	−21	−30	54
	L Superior Temporal Gyrus	19	−6.62	−54	−45	24
	R Lingual Gyrus	18	−9.70	12	−93	−2
	L Postcentral Gyrus	17	−7.39	−48	−21	51
	R Superior Medial Gyrus	14	−6.70	6	54	18
	L Cerebellum (VI)	13	−6.62	−30	−66	−19
	L Middle Frontal Gyrus	10	−6.96	−39	54	14
	L Thalamus	10	−8.27	−9	−24	18
TD > Dyslexia	R Paracentral Lobule	110	11.74	9	−30	74
	L Posterior-Medial Frontal		7.31	0	−6	67
	L Postcentral Gyrus	96	10.51	−42	−33	64
	L Postcentral Gyrus		6.63	−27	−45	70
	L Precentral Gyrus		8.39	−36	−12	64
	L Medial Cingulate Cortex	55	8.46	−9	−18	47
	L Middle Frontal Gyrus	24	7.47	−24	9	64
	L Superior Temporal Gyrus	22	9.18	−60	−6	4
	L Precuneus	19	9.03	−3	−54	11
	R Precentral Gyrus	17	8.88	45	−21	61
	Cerebellar Vermis (6)	13	8.23	0	−66	−12
	L Paracentral Lobule	12	8.72	−15	−30	74
	R Rolandic Operculum	10	6.39	45	−12	18
	L Temporal Pole	10	6.24	−48	9	−12
Dyslexia > TD	R IFG (Triangularis)	140	−7.56	54	33	4
	R Middle Orbital Gyrus		−7.52	24	27	−15
	R Cuneus	123	−10.85	21	−96	14
	L IFG (Orbitalis)	87	−10.02	−33	27	−15
	R Superior Medial Gyrus	87	−9.32	3	54	14
	L Superior Occipital Gyrus	77	−9.73	−18	−87	14
	R Postcentral Gyrus	76	−7.49	24	−45	57
	L Inferior Occipital Gyrus	36	−8.16	−39	−81	−2
	L Cerebellum	28	−6.42	−27	−63	−12
	L Insula Lobe	27	−6.35	−33	−3	−9
	L Hippocampus	26	−8.03	−27	−39	4
	R Superior Frontal Gyrus	24	−6.87	21	−15	61
	L Thalamus	22	−8.31	−12	−21	18
	L Postcentral Gyrus	22	−6.19	−24	−45	57
	L Postcentral Gyrus	21	−8.69	−24	−30	51
	L Middle Frontal Gyrus	21	−7.85	−21	−15	54
	L IFG (Triangularis)	21	−7.76	−54	27	4
	R Thalamus	21	−7.67	21	−33	8
	R Posterior-Medial Frontal	17	−7.12	12	3	64
	R Middle Orbital Gyrus	14	−6.40	45	48	−9
	L Superior Medial Gyrus	14	−5.81	0	39	37
	R Precentral Gyrus	13	−7.91	45	−15	47
	R Precentral Gyrus	13	−6.25	54	6	41
	R Middle Temporal Gyrus	12	−6.36	60	−39	−5
	R Lingual Gyrus	11	−6.16	12	−78	8
	R Inferior Parietal Lobule	10	−6.18	33	−57	51
SpD > Dyslexia	R Superior Frontal Gyrus	287	−11.71	18	18	61
	R Precentral Gyrus		−10.22	24	−27	70
	L Posterior-Medial Frontal		−9.15	−6	6	67
	R Superior Temporal Gyrus	138	−9.08	57	−33	8
	L Superior Temporal Gyrus	86	−9.24	−51	−48	28
	R Heschls Gyrus	69	−8.84	48	−12	14
	R Superior Temporal Gyrus		−5.25	66	−24	14
	L Superior Temporal Gyrus	62	−9.92	−63	−9	11
	L Postcentral Gyrus	62	−8.96	−45	−15	47
	L Superior Frontal Gyrus	19	−7.18	−18	21	61
	L Postcentral Gyrus	18	−6.99	−27	−36	70
	R Paracentral Lobule	14	−7.23	12	−36	74
	R Putamen	10	−6.90	15	3	−5
Dyslexia > SpD	L Inferior Temporal Gyrus	580	9.23	−39	−24	−15
	L IFG (Orbitalis)		8.63	−33	27	−12
	L Medial Temporal Pole		8.62	−45	15	−25
	R IFG (Orbitalis)	196	8.70	24	24	−12
	R Superior Orbital Gyrus		8.27	18	48	−9
	R Temporal Pole		8.07	48	18	−22
	L Lingual Gyrus	151	10.30	−21	−93	−9
	L Inferior Occipital Gyrus		8.50	−42	−72	−5
	R Inferior Occipital Gyrus	114	9.41	45	−84	−5
	R Middle Occipital Gyrus		7.90	24	−93	14
	L Middle Occipital Gyrus	86	11.91	−21	−87	14
	R Middle Temporal Gyrus	82	8.88	45	−27	−5
	R Superior Temporal Gyrus		8.29	66	−18	−2
	R Caudate Nuclues	71	9.08	9	21	8
	L Caudate Nucleus		7.76	−15	24	−5
	L Superior Temporal Gyrus	45	10.30	−45	−36	14
	R Superior Parietal Lobule	34	7.51	18	−51	61
	L Medial Cingulate Cortex	33	7.16	−3	0	41
	L Superior Frontal Gyrus	31	7.65	−9	48	41
	R Hippocampus	26	9.14	24	−33	8
	L IFG (Orbitalis)	23	9.03	−54	24	1
	R Superior Occipital Gyrus	23	7.20	21	−72	51
	L Superior Orbital Gyrus	22	5.98	−15	57	−9
	R Middle Temporal Gyrus	21	6.54	42	−57	8
	R Precentral Gyrus	17	6.92	54	6	41
	L Paracentral Lobule	16	5.94	−6	−27	57
	R Inferior Parietal Lobule	14	6.75	36	−51	54
	L Mid Orbital Gyrus	12	5.46	0	51	−2
	L Superior Medial Gyrus	10	5.71	0	54	11

Table 4. Results of group comparisons for the condition “pseudohomophones” displayed with FWE correction at the voxel level, p < .05. Clusters ≥ 10 voxels are reported.

				MNI
Comparison	Region	Voxel extent	t	x	y	z
TD > SpD	R Posterior-Medial Frontal	158	9.20	3	−18	70
	L Medial Cingulate Cortex		7.06	0	−3	47
	L Temporal Pole	93	10.44	−48	12	−15
	R Middle Temporal Gyrus	45	8.31	54	−21	−5
	L Lingual Gyrus	36	9.54	−21	−93	−9
	L Middle Temporal Gyrus	18	7.57	−66	−33	−9
	R Precentral Gyrus	11	6.67	54	−3	41
	L Thalamus	10	7.52	−9	−3	−5
	L Inferior Temporal Gyrus	10	7.20	−45	−72	−5
	L Inferior Temporal Gyrus		6.99	−39	−24	−15
SpD > TD	R Rolandic Operculum	312	−8.85	57	−12	18
	R Middle Temporal Gyrus		−8.26	63	−39	−2
	R Superior Temporal Gyrus		−8.06	42	−36	18
	R Lingual Gyrus	175	−8.07	24	−66	8
	R Fusiform Gyrus		−6.36	30	−87	1
	R Precentral Gyrus	116	−12.46	45	−12	51
	L Rolandic Operculum	84	−11.40	−54	−12	18
	L Postcentral Gyrus	69	−9.56	−48	−21	51
	L Precentral Gyrus		−6.75	−27	−27	51
	R Superior Frontal Gyrus	61	−9.33	21	18	61
	L Lingual Gyrus	58	−12.43	−27	−63	8
	L Cerebellum (VI)	51	−7.93	−30	−66	−19
	R Superior Frontal Gyrus	45	−7.46	18	−3	67
	R Cerebellum (VI)	38	−8.07	21	−78	−15
	R Lingual Gyrus	24	−10.74	12	−93	−2
	R Cerebellum (VI)	20	−6.39	21	−57	−19
	L Calcarine Gyrus	15	−7.05	−6	−93	−2
	L IFG (Triangularis)	14	−6.29	−45	12	14
	L Superior Temporal Gyrus	12	−6.37	−54	−45	24
	L Thalamus	11	−7.02	−9	−24	18
	L Middle Temporal Gyrus	10	−6.07	−54	−60	11
	R Middle Occipital Gyrus	10	−6.06	30	−84	37
TD > Dyslexia	R Paracentral Lobule	178	10.50	9	−30	74
	L Posterior-Medial Frontal		8.82	0	−6	67
	R Postcentral Gyrus		6.39	33	−39	67
	L Superior Temporal Gyrus	69	7.61	−51	−48	18
			6.59	−60	−30	21
	L Postcentral Gyrus	53	8.78	−27	−36	70
			7.45	−45	−36	61
	L Medial Cingulate Cortex	47	8.33	−9	−18	44
	R Rolandic Operculum	31	7.15	45	−12	18
	L Superior Temporal Gyrus	29	10.32	−60	−6	4
	L IFG (Opercularis)	22	7.95	−57	9	28
	R Precentral Gyrus	20	9.12	54	−6	47
	R Cerebellum (VI)	16	6.66	30	−48	−29
	L Precentral Gyrus	15	6.53	−33	−9	64
	L IFG (Triangularis)	13	5.57	−48	27	21
	L Paracentral Lobule	12	8.03	−15	−30	74
	R Superior Temporal Gyrus	11	7.86	54	−30	4
	R Precentral Gyrus	11	7.43	45	−21	61
Dyslexia > TD	R Calcarine Gyrus	249	−11.66	21	−84	18
	R Middle Temporal Gyrus		−7.87	57	−63	21
	R Middle Temporal Gyrus		−7.43	60	−39	−5
	R IFG (Orbitalis)	228	−9.87	51	33	1
	R Middle Orbital Gyrus		−8.26	24	27	−15
	R Middle Orbital Gyrus		−7.49	36	57	−9
	R Superior Medial Gyrus	187	−8.84	3	54	14
	R Superior Frontal Gyrus		−6.58	18	45	44
	L Superior Medial Gyrus		−6.57	0	39	37
	R Middle Orbital Gyrus	122	−9.92	6	24	−9
			−7.85	9	48	−5
	L IFG (Orbitalis)	114	−9.60	−36	24	−15
	R Postcentral Gyrus	104	−6.65	24	−45	57
	L Precuneus		−6.16	0	−57	47
	L Superior Occipital Gyrus	83	−10.37	−18	−87	14
	L Middle Temporal Gyrus	57	−7.20	−54	−66	21
	L Hippocampus	43	−9.10	−27	−39	4
	L Lingual Gyrus	40	−6.46	−12	−66	−5
	L Insula Lobe	40	−6.22	−33	−3	−9
	L Inferior Occipital Gyrus	35	−9.34	−36	−81	−2
	L Postcentral Gyrus	23	−9.15	−24	−30	51
	L Precentral Gyrus	21	−8.16	−21	−15	54
	R Thalamus	21	−7.66	18	−36	8
	R Lingual Gyrus	18	−7.85	12	−93	−2
	L Medial Cingulate Cortex	18	−6.33	−12	−45	47
	R Superior Orbital Gyrus	17	−8.00	15	51	−9
	R Lingual Gyrus	12	−5.94	21	−63	4
	L IFG (Orbitalis)	11	−6.17	−54	27	1
	L Lingual Gyrus	10	−8.48	−27	−57	1
	R Precentral Gyrus	10	−8.08	45	−15	47
	L Thalamus	10	−6.91	−12	−21	18
	L Lingual Gyrus	10	−6.74	−18	−75	1
	R Superior Frontal Gyrus	10	−6.21	21	−15	61
SpD > Dyslexia	R Precentral Gyrus	498	11.91	51	−12	51
	R Precentral Gyrus		9.73	24	−27	70
	L Postcentral Gyrus		10.50	−45	−15	51
	R Rolandic Operculum	350	11.06	48	−12	18
	R Rolandic Operculum		5.79	36	−27	24
	R Superior Temporal Gyrus		10.42	57	−33	8
	L Superior Temporal Gyrus	116	11.90	−63	−9	11
	L Superior Temporal Gyrus	115	8.95	−57	−42	18
	R Cerebellum (VI)	77	9.44	27	−78	−19
	R Cerebellum (VI)		6.51	24	−57	−22
	R Superior Frontal Gyrus	46	12.39	18	18	61
	L IFG (Triangularis)	19	6.30	−45	12	11
	L IFG (Triangularis)	17	8.56	−48	42	14
	R Lingual Gyrus	12	6.88	21	−72	8
	L Lingual Gyrus	11	9.09	−27	−63	8
Dyslexia > SpD	R IFG (Orbitalis)	371	−10.86	33	30	−12
	R Superior Orbital Gyrus		−10.55	18	48	−9
	R Middle Orbital Gyrus		−7.95	42	48	−9
	L Medial Temporal Pole	179	−9.50	−45	15	−22
	L Superior Orbital Gyrus		−8.22	−21	30	−9
	L Rectal Gyrus	121	−7.81	−12	30	−9
	R Olphactory Cortex		−7.05	9	21	8
	R Mid Orbital Gyrus		−5.58	9	33	−9
	R Middle Temporal Gyurs	87	−9.05	45	−27	−5
	R Superior Temporal Gyrus		−6.33	63	−18	−2
	L Inferior Temporal Gyrus	72	−9.43	−39	−24	−15
	L Hippocampus		−6.59	−27	−39	4
	L Superior Medial Gyrus	60	−8.37	−6	51	41
	R Inferior Temporal Gyrus	49	−8.19	48	−78	−5
	L Middle Temporal Gyrus	49	−7.76	−54	−36	−9
	L IFG (Orbitalis)	47	−7.52	−45	45	−9
	L IFG (Orbitalis)		−7.05	−54	24	1
	L Middle Occipital Gyrus	44	−10.46	−21	−87	14
	L Superior Temporal Gyrus	36	−10.05	−45	−36	14
	L Superior Temporal Gyrus	34	−6.26	−42	−15	−2
	L Medial Cingulate Cortex	31	−7.66	−3	−3	41
	R Precuneus	30	−6.66	15	−54	61
	L Inferior Occipital Gyrus	29	−6.72	−42	−72	−5
	L Parahippocampal Gyrus	24	−6.70	−21	−30	−9
	L Middle Temporal Gyrus	20	−6.97	−63	−12	−19
	R Middle Temporal Gyurs	18	−6.22	45	−57	8
	L Lingual Gyrus	17	−8.04	−21	−90	−9
	R Thalamus	13	−7.03	21	−33	8
	L Cerebellum (VI)	12	−6.55	−18	−78	−9
	L Superior Medial Gyrus	12	−5.70	−3	57	8

Table 5. Brain activity for the contrast words vs. pseudohomophones in the whole sample. Clusters are displayed with FWE correction at the voxel level, p < .05. Clusters ≥ 10 voxels are reported.

			MNI
Region	Voxel extent	t	x	y	z	Voxel extent of manually defined ROIs
L IFG (Triangularis)**	532	7.45	−42	30	18	78
L IFG (Orbitalis)**		8.00	−36	21	−2	96
L IFG (Opercularis)**		8.41	−51	9	21	109
L Superior Parietal Lobule**	185	7.92	−24	−69	51
L Posterior-Medial Frontal	156	7.60	−6	12	54
R Superior Occipital Gyrus	101	8.09	27	−66	47
R IFG (Orbitalis)**	64	7.04	36	24	−2
L Fusiform Gyrus**	18	6.13	−42	−72	−9
L Inferior Parietal Lobule**	17	5.96	−48	−42	51
Caudate Nucleus	10	5.28	−15	9	8
R Precuneus	1258	−7.97	3	−51	47
L Calcarine Gyrus		−7.84	−9	−69	24
R Precuneus		−6.98	12	−66	31
L Middle Temporal Gyrus	244	−7.80	−54	−63	24
R Supramarginal Gyrus	201	−7.75	57	−48	31
R Superior Frontal Gyrus	65	−6.37	24	30	44
L Middle Frontal Gyrus	33	−5.73	−30	24	41
R Middle Temporal Gyrus	32	−5.98	57	−9	−15

Note. ** indicates clusters included in the ROI analysis. IFG: Inferior Frontal Gyrus.

Figure 3. Group-related activity for words vs. pseudohomophones in each selected ROI based on the results of the whole-brain analysis, FWE-corrected at the voxel level, p < .05. Dark-grey boxes indicate functional activity for words, light-grey boxes for pseudohomophones. Bars represent standard errors.