Protanopes and deuteranopes (red-green dichromats) lack, respectively, long (L) or medium (M) wavelength-sensitive cones because of genetic factors (Neitz & Neitz, 2011).
2014) found different selections for real protanopes and real deuteranopes.
Age in Years Protanope Deuteranope Tritonope 30-40 -- -- -- 41-50 -- -- -- 51-60 1 1 -- 61-70 -- -- --
Out of these 30 subjects, 22 subjects were tritonope, 4 protanope, and 4 deuteranope, which is in agreement with the study published by Sinha A K, Bhatia R et al.
This is because the recognition criterion required identification of whether a stop or go traffic light signal was displayed, and deuteranopes are known to have difficulty recognizing the colors of signal lights (Vingrys & Cole, 1988).
Search conspicuity for the deuteranopes is about 60% of that found for color-normal observers, except for the yellow warning signs, green direction signs, blue parking signs, and speed restriction signs, for which conspicuity did not differ between the two groups of observers.
The differences are statistically significant, except for normal participants between G and Y signals, for deuteranomals between G and Y signals, for deuteranopes between R and Y signals, for protanomals for Y signals with both R and G signals, and for protanopes for Y signals with both R and G signals.
The deuteranopes showed the greatest increases in response time, 53% for R and 85% for Y, relative to those of normals.
The classification plates are more effective for deuteranopes
than protanopes, with a correct classification possible for around 90% of deuteranopes
and around 80% of protanopes.