What is the role of tone in the phonological similarity effect?

To recall a list of phonologically similar words is more difficult than to recall a list of phonologically dissimilar words; this is the well-known phonological similarity effect in verbal working memory. However, it is hypothesized that not all phonological aspects of a word would create the phonological similarity interference in verbal working memory. The present study examines the influence of different phonological characteristics of the to-be-memorized items on participants' recall performance. Convergent results from two experiments revealed the phonological similarity effect was less evident with same tone materials. These results are discussed in terms of the role of tone in the phonological similarity effect in verbal working memory.