Table 1.

Stimulus conditions and perceptual dominance

Subject	Eye	Contrast	Grating	High contrast			Low contrast
	dominance	L/H (%)	Cyc/deg	M	%	Σ	M	%	Σ
S1	Left	17/70	0.4	9.3	68	116	4.0	29	112
S2	Right	17/70	0.4	4.2	55	201	3.0	39	201
S3	Right	14/70	0.5	6.1	31	77	4.9	35	108
S4	Right	20/70	0.4	5.1	49	306	3.5	34	309
S5	Right	20/70	0.4	4.0	59	346	2.0	28	332

The high-contrast grating was presented to the dominant eye. The contrast and spatial frequency of the gratings were adjusted individually to maximize the contrast difference while maintaining an adequate predominance duration. Psychophysical data for average perceptual duration (M), predominance—the percentage of time that the subject reported perceiving each of the two stimuli (%) –- and number of occurrences (Σ) are reported for perceptions of high-contrast and low-contrast gratings. Predominance times do not total 100%; subjects perceived a piecemeal mixture of the stimuli during the remaining time.