Table 2.

Psychophysical experiments: behavioral data

Group	Case	Extraction of 3D shape				Extraction of 2D shape				Extraction of features
Group	Case	Shading	Texture	Motion	Disparity	Luminance	Texture	Motion	Disparity^{^b}	Luminance	Texture	Motion	Disparity^{^b}
PCA	1	0.48	1.38	1.31	0.60	−2.19	−0.63	−0.56	−1.68	−0.24	−1.05	−0.11	0.80
	2	1.09	1.40	0.84	0.58	−1.61	−0.21	0.57	0.97	0.69	−0.90	−0.38	0.66
	3	1.42	1.64	0.68	0.70	−0.88	0.66	0.61		−0.14	−0.60	0.57
	4	0.64	0.60	0.38	0.56	−1.41	−0.18	0.40		−0.93	−0.86	−0.56	0.05
	5	1.33	1.97	0.91	0.54	−0.06	0.79	0.36	0.33	−0.02	−0.37	−0.12	−0.31
	6^{^a}	0.78	1.44	0.25		−1.14	−0.03	0.49		−0.35	−1.07	−0.40
	7	1.26	0.92	0.69	0.58	−1.22	−0.48	0.44		−0.04	−0.83	−0.38
	8	1.31	1.69	1.70	1.78	−0.80	−0.11	0.56	−1.31	−0.28	−0.37	−0.28
	9	1.71	2.46	2.22	1.54	−0.40	0.62	0.42	0.45	0.52	−0.41	0.04
	10	0.82	2.30	2.28	1.10	−1.15	0.01	−0.06	−1.16	0.60	0.42	0.61	0.08
	11	0.86	1.14	0.70	0.49	−1.31	0.71	−0.55	0.51	−0.61	−1.02	−0.42	−0.93
	12	0.66	2.09	1.89	0.50	−0.84	−0.43	0.53	−0.61	−0.34	−0.54	−0.24	−0.95
	13	0.62	0.73	0.14	0.37	−1.58	−0.75	0.52		0.25	−0.41	−0.27
	Mean	1.00	1.52	1.08	0.78	−1.12	0.00	0.29	−0.31	−0.07	−0.62	−0.15	−0.32
	SEM	0.11	0.16	0.20	0.13	0.15	0.15	0.11	0.35	0.13	0.11	0.10	0.23
	Impaired (n)	9	11	10	2	10	9	11	0	11	8	11	0

DLBD	Mean	1.13	1.40	0.91	1.07	−1.39	−0.22	−0.62	−0.51	−0.64	−0.91	−0.46	−0.06
DLBD	SEM	0.20	0.20	0.16	0.24	0.17	0.17	0.32	0.37	0.07	0.12	0.08	0.19
	Impaired (n)	9	9	9	4	6	4	4	0	2	3	5	1

AD	Mean	0.85	0.86	0.62	1.03	−1.50	−0.30	−0.56	−1.30	−0.72	−0.77	−0.41	−0.57
AD	SEM	0.13	0.13	0.14	0.24	0.12	0.13	0.25	0.10	0.06	0.10	0.09	0.17
	Impaired (n)	8	5	7	4	7	4	4	0	3	4	7	0

Controls	Mean	0.37	0.48	0.19	0.61	−1.88	−0.77	−1.17	−0.49	−0.83	−1.20	−0.79	−0.29
	SEM	0.04	0.04	0.02	0.08	0.04	0.06	0.11	0.20	0.04	0.04	0.04	0.12

Significant group difference		Yes	Yes	Yes	No	Yes	Yes	Yes	No	Yes	Yes	Yes	No

Extraction of 3D shape. Test scores reflect the error-in-depth (in centimeters) between the global maximum indicated by the participant and the true global maximum; extraction of 2D shape and extraction of features, test scores reflect the contrast between neighboring bars of the gratings (expressed as logarithmic Michaelson contrasts) to achieve an average performance of 82%. Test scores in bold indicate significantly decreased performance compared with the control population (one-sided, p < 0.05) (Crawford and Garthwaite, 2002). Cases 1, 2, 6, 7, and 12 (underlined) participated in the fMRI experiment.
↵^aOnly monocular cues were tested in Case 6, who was congenitally blind in one eye.
↵^bFor the disparity-defined stimuli, we observed an interaction between the time needed to perceive stereograms and the QUEST procedure. This resulted in the inability to define a threshold in some participants (indicated by an empty cell) and a less reliable threshold in the other participants.