Training letter discrimination in four-year-old children

Four-year-old children were tested on letter discrimination. Subjects in two experimental groups went through an experimental training program on a match-to-sample apparatus. Subjects in the experimental-critical group were given reinforcers for responding to features of the stimuli thought critical for discriminating letters while subjects in the experimental-noncritical group were given reinforcers for responding to non-critical features. Subjects went through the training program daily until they reached criterion; then they were posttested on letters. Subjects in a control group received no training but were posttested. Subjects in all groups made fewer errors on the posttest. Subjects in the experimental-critical group made significantly fewer posttest errors than subjects in the experimental-noncritical group, lending support to the hypothesis that reinforcement of discriminative responding to critical features of letter-like stimuli results in greater improvement in letter discrimination than reinforcement of discriminative responding to noncritical features of stimuli. Analysis of confusion matrices provided tentative indications of the nature of letter confusions in 4-yr-old children.