STEREOACUITY CHANGES IN INFANCY MEASURED BY PREFERENTIAL-LOOKING

Title STEREOACUITY CHANGES IN INFANCY MEASURED BY PREFERENTIAL-LOOKING
Author, Co-Author Paulette Schmidt, Ivan Wood, Sarah Lewin, Helen David
Topic
Year
1992
Day
Sunday
Program Number
Poster 38
Room
Great Hall
Affiliation
Abstract The change in random dot stereoacuity (RDS) was measured using Lang and RDE stereo stimuli in 44 fullterm infants randomly selected from birth records of the Hazel Grove Health Clinic (U.K.) In a 2AFC preferential-looking paradigm, estimates of stereo threshold were determined in visually normal 2-18 month olds using a modified staircase procedure. Stimulus disparities ranged from 1200 to 201 and 756 to 52 arc seconds (") on the Lang and RDE tests respectively. The results show that infants 1) below the age of 6 months produced mean stereo thresholds of 1166" (t=+118", n=13) AND 756" (t=+0.0, n=8) respectively on Lang and RDE tests, 2) between 6 and 12 months Lang stereo thresholds increased to 811" (t=+313", n=16), and 3) from 12 to 18 months thresholds increased to 459" (t=+150", n=15). Interestingly, infants unable to overcome a 20 prism diopter base out showed significantly lower stereoacuities than those able to do the test. A Paired T test showed no significant difference for the Lang (T=0.91, p=0.36, n=41) or RDE (T=0.83, p=0.41, n=20) between repeated measured of stereothreshold on the same test. These changes in stereoacuity will be compared with other studies of infant stereoacuity.
Affiliation of Co-Authors
Outline