METHODS

Subjects

There were 6 males and 2 females between the ages of 21-25. All were students at the State College of Optometry. All had less than 25 A of convergence ability as demonstrated on the Topper vectogram, on RDS convergence pretests, and on phorometric testing using Risley prisms at 40 cm. The eight subjects were then matched according to average convergence ability and randomly assigned to one of two groups, experimental or control.

The apparatus and stimuli were the same as described previously. Both groups received the same instructions and experiences as had the patients in experiment 1 except that the convergence demand was

always set at zero (superimposition of RDS) for the control group. After experimental subjects had received approximately four sessions of RDS convergence training, the control subjects received a second baseline convergence test. The control subjects then received RDS convergence training for two sessions.

RESULTS

Figs. 6-9 represent the performance of each matched pair of subjects during baseline and experimental sessions. The top panel depicts the RDS convergence training performance, as well as vectogram test performance, of the experimental subjects. The bottom panel shows the performance of control subjects. it is readily apparent that during RDS convergence training ses