Using a single test to measure human contrast sensitivity from early childhood to maturity.

Despite the emerging scientific and clinical importance of measuring human contrast sensitivity (CS), developmental data are sparse, especially those obtained with a single methodology. We used a new, time-efficient, psychophysical card procedure to evaluate binocular CS in groups of 20 4- to 9-yr-olds and 10 adults. Combined with data from infants and toddlers obtained previously with the same method, our results show that CS is adult-like by 9 years of age. However, the pattern of development is asymmetrical across spatial frequency (SF): Sensitivity at high SF (which is very poor near birth) shows dramatic improvement over the first three years, but sensitivity at low SF shows much more gradual development, a result which may be explained by differences in the maturation of the underlying neural SF channels. Also notable is that the method shows clinical potential due to its relative speed, ease of use, and consistent results across such a broad age range.