The effects of dimensional naming upon children's performance in a modified optional shift problem.

In a modified optional shift paradigm, shift and test tasks were administered concurrently to 120 second-grade children. Ss required, during shift learning, to verbalize the values of the previously relevant dimension showed an increase in reversal responding in the test task, whereas those required to verbalize the values of the previously irrelevant dimension showed an increase in nonreversal responding. The results are in good agreement with predictions made from an extension of Hull-Spence discrimination learning theory.