Color Perception Of Color Blind Monkeys

Abstract

sensitivity to long (L), middle (M) and short (S) wavelengths of light. Genes that encode Land Mare located in X chromosome, whereas that for S is in chromosome No.7. The loss of the gene that encodes either L or M photopigment in human will cause dichromatic color vision, generally known as colorblind. Molecular genetic analysis of more than 3000 macaque monkeys showed the existence of dichromatic genotype. The defect gene is located in the X chromosome. Males carrying this defect gene on their X chromosome would have protanope characteristic. Females carrying this defect gene on one of their X chromosomes would be heterozygous. Electroretinogram (ERG) measurement shows that the sensitivity to red light was extremely low in protanopic male monkeys compared to the normal genotype. Heterozygous carrier female has sensitivity that is intermediate between the genetic protanopes and normal monkeys. Operant conditioning technique was used to see the color perception of crab eating monkey. Two dichromatic and two normal male monkeys were trained to do a color discrimination task with food as a reward. The task is finding a circle containing red color. Result shows that both dichromatic monkeys were unable to see red color.