ABSTRACTThe contrast sensitivity function provides a more comprehensive and sensitive measure of spatial vision than does visual acuity. A large-sample study of contrast sensitivity during the adult years revealed that observers over age 60 have a substantial loss of sensitivity to intermediate and high frequencies. All observers wore their best possible optical correction for the test distance and were free from significant ocular pathology. We further report that older observers have difficulty perceiving faces under low contrast conditions, which is predictable from the characteristics of their contrast sensitivity functions.