INTERFERING WITH THE CENTRAL EXECUTIVE BY MEANS OF A RANDOM INTERVAL REPETITION TASK

Four dual-task experiments are reported in which a short-term memory t ask is performed concurrently with a random interval repetition task, which was designed to interfere with functions normally attributed to the central executive in the working memory model of Baddeley and Hitc h (1974). The task was found to interfere with supra-span serial recal l and with backward memory span, but did not disrupt performance on a forward-memory-span task. The effects were observed in dissociation wi th effects of articulatory suppression and matrix tapping, so that the locus of the effects of the new task is not due to the slave systems. In addition, single-task random-interval repetition performance was s ampled and compared to performance in the dual-task conditions of all four experiments. Although quality of tapping performance differed bet ween the single-task and the dual-task conditions, it was not related to recall performance. All the results are discussed with reference to the working memory model.