A method and apparatus for administering eye tests to identify cone sensitivity loss associated with hereditary and acquired color vision loss which may be used for early detection, progress, treatment, and monitoring of eye conditions, traumatic brain injury, optic neuritis, systemic and neurological diseases including Glaucoma, Retinopathy, Age-Related Macular Degeneration, Multiple Sclerosis, Alzheimers Disease, and Parkinsons Disease and retinal toxicity. Particularly, the method and apparatus disclosed uses a Cone Contrast Test (CCT) to test individuals for hereditary or acquired color vision loss associated with (a) early signs of potential disease/damage/toxicity in an effort to (i) provide opportunity for treatment, and (ii) prevent permanent eye damage, and (b) monitor progress and treatment of such disease/damage/toxicity. The system comprises a computer system including an input device and a display device, and the accuracy and repeatability of the testing is provided by repeated calibration using a colormeter.