Table 2.

Hemispheric asymmetry and anterior–posterior gradients of subfield atrophy in AD and SD patients.

Abbreviations: HC = healthy controls; AD = Alzheimer's disease; SD = semantic dementia; IQR = interquartile range. ANOVA were conducted with the Kruskal & Wallis H test and when significant (p < 0.05), two-by-two comparisons were assessed with the Mann–Whitney test. Significant (p < 0.05) results are shown in bold.

Increased hemispheric asymmetry indicates a stronger left/right volume difference but not the direction of this difference. Increased anterior–posterior gradient index indicates an increase in the volume of the anterior hippocampal compared to that of the total hippocampal volume. See main text (Section 2.4) for further information.

	Values: median (IQR)			Statistical comparisons
	HC	AD	SD	ANOVA	HC/AD	HC/SD	AD/SD
Hemispheric asymmetry
CA1	5.4 (1.8, 8.5)	7.8 (4.2, 17.0)	15.3 (13.1, 18.5)	H = 14.7 p < 10− 3	Z = 1.94 p = 0.05	Z = 3.67 p < 10− 3	Z = 1.86 p = 0.06
Subiculum	3.8 (1.6, 6.5)	6.6 (1.8, 8.1)	17.7 (12.7, 23.8)	H = 16.1 p < 10− 3	Z = 1.64 p = 0.10	Z = 3.91 p < 10− 3	Z = 2.42 p = 0.02
Other	5.2 (2.8, 9.8)	5.1 (1.9, 8.1)	11.4 (7.2, 14.4)	H = 7.2 p = 0.03	Z = − 0.82 p = 0.42	Z = 2.31 p = 0.021	Z = 2.53 p = 0.01
Global hippocampus	2.1 (1.2, 4.0)	4.7 (2.8, 7.1)	14.2 (11.2, 16.1)	H = 27.1 p < 10− 3	Z = 3.17 p = 0.002	Z = 4.41 p < 10− 3	Z = 3.25 p = 0.001
Anterior–posterior gradient
CA1	66.2 (63.4, 70.0)	66.6 (59.7, 70.1)	56.5 (52.9, 57.6)	H = 14.7 p < 10− 3	Z = − 0.33 p = 0.74	Z = − 3.80 p < 10− 3	Z = 3.08 p = 0.002
Subiculum	57.2 (53.2, 61.5)	60.1 (53.3, 65.6)	52.4 (44.8, 54.9)	H = 8.3 p = 0.02	Z = 1.02 p = 0.31	Z = 2.59 p = 0.01	Z = 2.47 p = 0.01
Other	62.8 (57.5, 66.7)	65.8 (57.1, 70.4)	59.7 (55.5, 61.9)	H = 3.03 p = 0.22	–	–	–
Global hippocampus	62.4 (59.0, 65.1)	64.6 (58.2, 68.5)	55.6 (52.0, 59.0)	H = 9.3 p = 0.009	Z = 0.60 p = 0.55	Z = 2.95 p = 0.003	Z = 2.53 p = 0.01