Stereoacuity in mentally retarded and intellectually normal adolescents

Stereoacuity was measured in 30 intellectually normal and 30 mentally retarded adolescents, matched for age and sex, using the Titmus stereo test to provide nasalward and temporalward target disparities. The intellectually normal group had significantly better stereoacuity for both types of disparity. No statistically significant differences between nasal and temporal disparities were found within groups. A learning effect is shown for the mentally retarded.