Irrelevant speech eliminates the word length effect

The word length effect refers to the observation that memory is better for short than for long words. The irrelevant speech effect refers to the finding that memory is better when items are presented against a quiet background than against one with irrelevant speech. According to Baddeley's (1986, 1994) working memory, these variables should not interact: The word length effect arises from rehearsal by the articulatory control process, whereas irrelevant speech reduces recall through interference in the phonological store. Four experiments demonstrate that, like articulatory suppression, irrelevant speech eliminates the word length effect for both visual and auditory items. These results (1) provide further evidence against the ability of working memory to explain the word length and irrelevant speech effects and (2) confirm a specific prediction of Nairne's (1990) feature model.