The phonological similarity effect refers to the finding that a list of sim
ilar-sounding items is recalled less well than a list of dissimilar-soundin
g items. A strong prediction of the phonological store hypothesis, based on
Baddeley's (1986, 1992) working memory framework, is that irrelevant speec
h should inter;act with the phonological similarity effect. We report three
experiments that demonstrate that irrelevant speech eliminates the phonolo
gical similarity effect for visual but not for auditory items. In this resp
ect, irrelevant speech functions much like articulatory suppression. Implic
ations for the phonological store and changing state hypotheses are discuss
ed.