Development and Validation of Paradigms Based on the Global-First Topological Approach for Alzheimer’s Disease Severity Staging

Figures & data

Table 1 Comparison of Demographic Variables Between Different Groups

Variables	HE	MCI	AD	Intra-Group p value
				F	p
Age	62.17±7.39	62.89±9.57	67.08±8.30	2.63	0.078
Education years	11.72±3.31	10.56±3.66	9.88±3.73	1.89	0.157
Gender	1.41±0.50	1.42±0.50	1.65±0.48	2.15	0.123
MMSE	28.93±1.03	25.72±2.21	20.69±2.60	111.69	0.000**
MoCA	27.59±1.90	20.72±3.00	14.00±2.67	187.677	0.000**
GDS	1.21±0.41	2.40±0.50	3.29±0.60	121.551	0.000**

Notes: **p < 0.01. Comparisons between groups were assessed by the ANOVA test.

Abbreviations: MMSE, Mini-Mental Status Examination; MoCA, Montreal Cognitive Assessment; GDS, Global Deterioration scale; HE, Healthy elderly; MCI, Mild cognitive impairment; AD, Alzheimer’ s disease.

Figure 1 (a) Set A is dominated by proximity organizations; Set B adds a background image around Set A, comparing proximity organizations to make similarity organizations dominant. (b) The task is to determine whether the large and small shapes are triangles or arrows, respectively.

Figure 2 (a) Schematic depiction of the stimulus groups for Experiment 2 and (b) Schematic description of Experiment 2, the no-change pattern was presented in the first display and the no shape change, the non-topological change, or the topological change pattern was presented in the second display randomly.

Table 2 RTs of Perceptual Organization Under Different Tasks in Different Groups

		Proximity				Similarity
		Global		Local		Global		Local
		Consistent	Inconsistent	Consistent	Inconsistent	Consistent	Inconsistent	Consistent	Inconsistent
Group	YC	439.04±62.03	453.72±58.53	502.84±62.26	548.00±59.39	524.08±77.22	582.80±85.67	456.60±66.83	471.46±69.35
	HE	601.77±116.67	635.35±135.84	627.03±153.61	674.04±191.77	687.96±129.59	766.56±150.26	668.30±139.81	683.74±138.04
	MCI	846.95±249.52	922.76±291.86	852.19±242.02	911.29±246.68	1017.78±354.73	1158.74±343.14	887.95±235.99	942.93±264.45
	AD	1101.67±263.89	1245.04±362.11	1081.57±363.73	1180.04±353.85	1415.64±486.75	1675.14±608.88	1131.57±325.93	1297.14±470.10
F		49.12				43.85
pc		0.001**				0.001**
ηp^2		0.56				0.53

Notes: p_c: after the Bonferroni correction; **p < 0.01.

Abbreviations: YC, Young control, HE, healthy elderly, MCI, mild cognitive impairment; AD, Alzheimer’s disease.

Figure 3 Estimated mean values (and standard error) of RTs (in ms) for each group, task, and consistency in the perceptual organization task; (a) Set A is dominated by proximity organizations and (b) Set B is dominated by similarity organizations.

Table 3 Comparison of Visual Working Memory Variables Between Different Groups

Groups	Number	Same	Non-Topological Change	Topological Change	Inter-Group p value
					F	p	Partial Eta^2
HE	2	0.926±0.067	0.890±0.109	0.865±0.092	6.290	0.003**	0.183
	3	0.828±0.116	0.793±0.110	0.761±0.110	3.990	0.024*	0.125
MCI	2	0.894±0.085	0.872±0.078	0.835±0.110	8.193	0.001***	0.167
	3	0.774±0.102	0.735±0.087	0.702±0.087	7.369	0.001***	0.152
AD	2	0.694±0.168	0.644±0.143	0.663±0.141	2.587	0.086	0.101
	3	0.616±0.116	0.600±0.113	0.589±0.109	0.531	0.091	0.023

Notes: *p < 0.05, **p < 0.01, ***p < 0.001. Comparisons in groups were assessed by the ANOVA test.

Abbreviations: HE, healthy elderly, MCI, mild cognitive impairment; AD, Alzheimer’s disease.

Figure 4 The differences of VWM levels in different size conditions compared to different groups; *p < 0.05. **p < 0.01.