Retroactive effects of irrelevant speech on serial recall from short-term memory

Five serial recall experiments are reported. In four of the five it is shown that irrelevant sound (IS) has a retroactive effect on material already in memory. In the first experiment, IS presented during a filled retention interval had a reliable effect on list recall. Four further experiments, three of which used retroactive IS, showed that IS continued to have an effect on recall following a long, filled retention interval. Articulatory suppression during visual input was found to abolish the long-lasting, retroactive effect of IS, supporting the idea that IS affects the phonological loop component of short-term memory. IS also, therefore, seems to affect a longer term memory system with which the loop interacts.