Effect of reinforcement of visual acuity in myopic adults

In two experiments, attempts were made to improve visual acuity through reinforcement. In Experiment I, four myopic subjects were given five blocks of 24 trials in a conditioning task. The target stimuli were slides of Landolt rings, with 14 different sizes (increasing on a logarithmic scale) and 12 different stimuli representing each size. Trial blocks of contingent social approval for a correct response were alternated with noncontingent blocks in which approval was delivered randomly. Results permitted the interference that contingent approval resulted in increased acuity. In Experiment II, essentially the same task was used to compare the performance of three groups of subjects (each N=20): contingent reinforcement, noncontingent response, and no response control. Results showed a nonsignificant increase in acuity and a significant decrease in refractive error. Possible directions for further research are discussed, and ethical considerations are noted.