Figure 4.

Darks are perceived more accurately and faster than lights in observers with normal vision and observers with glaucoma. (A) Accuracy (percent of correct responses) was higher for darks (dark bars) than lights (light bars). (B) Reaction time was faster for darks than lights. The difference in reaction time between observers with normal vision and glaucoma reached significance only for light targets. The histograms illustrate means and standard errors of the mean. ***P < 0.001, **P < 0.01, *P < 0.05, not significant (ns) P > 0.05. Wilcoxon tests.