Table 1.
Hue-scale data for threshold (20–85% seen), monochromatic (580 nm), point stimuli with white or red fixation targets (experiment 1). Shown is the mean rating (after the arcsin transform) for all seen spots for each subject in each of the 5 categories (white, red, green, blue, and yellow) plus or minus the standard error. Ratings for each category are on a scale from 0–10. ‘Percent achromatic’ is the percent of seen stimuli, on a scale of 0–100, that were rated only as white (a rating of 10 in the white category). ‘Mean saturation’ is the average saturation (sum of all ratings other than white) for all seen stimuli on a scale of 0–100. Stimuli were presented foveally for subjects 1–4, and at 1° for subject 5.
| White fixation target | |||||
|---|---|---|---|---|---|
| subject 1 | subject 2 | subject 3 | subject 4 | subject 5 (1) | |
| number seen | 297 | 407 | 359 | 72 | 411 |
| percent achromatic | 42.4 ± 2.9 | 54.8 ± 2.5 | 48.7 ± 2.6 | 77.8 ± 5.0 | 35.8 ± 2.4 |
| mean saturation | 35.3 ± 2.3 | 37.3 ± 2.2 | 47.8 ± 2.6 | 7.3 ±1.6 | 25.6 ± 1.2 |
| mean white rating | 6.51 ± 0.23 | 6.30 ± 0.22 | 5.22 ± 0.26 | 9.41 ±0.16 | 7.44 ± 0.12 |
| mean red rating | 0.39 ± 0.08 | 0.38 ± 0.08 | 0.64 ± 0.12 | 0.03 ± 0.03 | 0.94 ± 0.09 |
| mean green rating | 1.34 ± 0.12 | 0.33 ± 0.08 | 2.98 ± 0.24 | 0 | 0.73 ± 0.09 |
| mean blue rating | 1.58 ± 0.14 | 2.82 ± 0.21 | 0.08 ± 0.04 | 0.18 ± 0.07 | 0.73 ± 0.07 |
| mean yellow rating | 0.45 ± 0.07 | 0.19 ± 0.05 | 1.08 ± 0.16 | 0.51 ± 0.15 | 0.36 ± 0.05 |
|
Red fixation target | |||||
| subject 1 | subject 2 | subject 3 | subject 4 | subject 5 (1) | |
| number seen | 336 | 314 | 331 | 76 | 429 |
| percent achromatic | 37.2 ± 2.6 | 54.4 ± 2.8 | 51.1 ± 2.8 | 51.3 ± 5.8§ | 20.7 ± 2.0‡ |
| mean saturation | 32.1 ± 1.9 | 36.5 ± 2.4 | 44.2 ± 2.6 | 15.5 ± 2.0# | 39.9 ± 1.4‡ |
| mean white rating | 6.82 ± 0.19 | 6.35 ± 0.24 | 5.58 ± 0.26 | 8.45 ± 0.20# | 6.01 ± 0.14‡ |
| mean red rating | 0.85 ± 0.12# | 1.26 ± 0.17‡ | 0.92 ± 0.15 | 0.54 ± 0.14# | 2.22 ± 0.14‡ |
| mean green rating | 0.95 ± 0.10# | 0.12 ± 0.05* | 2.29 ± 0.22* | 0.03 ± 0.03 | 1.01 ± 0.10* |
| mean blue rating | 1.30 ± 0.12 | 1.98 ± .21# | 0.18 ± 0.07 | 0* | 0.58 ± 0.06 |
| mean yellow rating | 0.38 ± 0.06 | 0.29 ± 0.07 | 1.04 ± 0.16 | 0.99 ± 0.18* | 0.55 ± 0.06# |
Superscripts indicate significant differences in the two conditions, with
p<0.05,
p<0.01,
p<0.001, and
p < 0.0001 (two-tailed z-test).
All subjects rated spots significantly more red or less green with the red fixation target. Some subjects also rated spots less blue (subject 2 and 4) or more yellow and more saturated (subject 4 and 5) with the red fixation target.