Show total color blindness found to be uncommon color blindness where an individual mistakes one color for another Is comparatively rare with the concu slon of red for or green most common j cases of 0 total color blindness says the th new york herald tribune where the person cannot distinguish between I 1 any colors at all are so uncommon t that interest Is warranted in a de I 1 script ton of such a case appearing in I 1 the journal of the optical society it fis Is reported by a psychologist of the t university of virginia so rare la Is total color blindness that 1 only cases have been found in the world and 11 in the united states i the subject tailed failed in all tests of col or blindness in the Holni holmgren gren wool tests tor for example the subject was j instructed to sort out the skeins into four piles red yellow green and blue he finally sorted them into five piles based solely on relative bright ness the subject in tact fact saw all scenes as one would in a non don chloi ed motion picture where all real colors become blacks grays and whites in human vision the acting mecha are the rods and cones in the eye the cones giving color perception and the rods black gray and white vision according to the simplest the ory from physiology it Is possible to predict that if the rods alone acted in vision the part of the spectrum where the eye Is most sensitive woul I 1 be in the green if the cones acted the intensity maximum should be at the yellow green tests on the sub eject strongly indicated the functioning of the rods alone I 1 |