Cone contrast test for detection of color vision deficiency

Award Year 

Performance experts at the Air Force Research Laboratory’s 711th Human Performance Wing, USAF School of Aerospace Medicine, have collaborated with Innova Systems, Inc., in the deployment of a new color vision test system. The Cone Contrast Test (CCT) is a software-generated clinical test that indicates vision defi ciency type and severity, and can quantify the realm of normal color vision. Th e CCT also can distinguish hereditary color vision loss from that caused (more) by disease, trauma, medications and environmental conditions, and facilitates the detection and monitoring of disease.Whether genetic or acquired, color vision defi ciency—commonly known as color blindness— makes it challenging, or even impossible, to hold certain jobs in military and civilian sectors alike. Current test methods typically provide only a pass/ fail determination. As a direct consequence to the USAF, candidates must be excluded as pilots if they have defi cient color vision, despite the relative degree of defi ciency. Furthermore, conventional testing is well-known to incorrectly label color vision as “normal” when it is actually defi cient.A person’s ability to see colors depends upon a complex mechanism involving the retina, a neuromembrane lining the inside-back portion of the human eye. Th e retina contains two types of lightsensitive cells, rods and cones, which convert light energy into signals carried via the optic nerve to the brain. Only the cones—characterized as red, green, and blue types—are sensitive to color. Th e CCT is superior to conventional color vision testing in that it presents a random sequence of colored letters, each visible to just one cone type at a time, in order to provide a cone-specifi c numeric score. Th is score determines the cone contrast sensitivity threshold, thereby enabling decisions about occupational selection and the risks posed to performance.As a direct result of the technology transfer eff ort implemented by the USAF Aerospace Medicine Consultation Service with Innova Systems, the CCT has been implemented at more than 100 active duty and reserve USAF bases. The testing availability will reduce travel to test-specifi c bases, netting the USAF an estimated savings of about $100,000 per year. Savings resulting from improved safety, performance, and accident avoidance could easily reach tens of millions of dollars for every military aircraft accident avoided. As the system is adopted commercially, persons with occupations in the aviation, transportation and fi rst responder industries will be tested to better determine their visual capabilities for operations in the colorrich world of digital display panels, in which undetected defi ciency, however slight, can become problematic. (less)