Phonological similarity effect in complex span task

Abstract

The aim of our study was to test the hypothesis that two systems are involved in verbal working memory; one is specifically dedicated to the maintenance of phonological representations through verbal rehearsal while the other would maintain multimodal representations through attentional refreshing. This theoretical framework predicts that phonologically related phenomena such as the phonological similarity effect (PSE) should occur when the domain-specific system is involved in maintenance, but should disappear when concurrent articulation hinders its use. Impeding maintenance in the domain-general system by a concurrent attentional demand should impair recall performance without affecting PSE. In three experiments, we manipulated the concurrent articulation and the attentional demand induced by the processing component of complex span tasks in which participants had to maintain lists of either similar or dissimilar words. Confirming our predictions, PSE affected recall performance in complex span tasks. Although both the attentional demand and the articulatory requirement of the concurrent task impaired recall, only the induction of an articulatory suppression during maintenance made the PSE disappear. These results suggest a duality in the systems devoted to verbal maintenance in the short term, constraining models of working memory.

Keywords:

• Working memory
• Phonological similarity
• Complex span task
• Rehearsal
• Time-based resource-sharing model

This work formed part of the second author's PhD thesis. It was supported by a grant from Institut Universitaire de France to the first author and from the Ministère de la Recherche for the second author. We thank Marie-Aude Bardier, Christelle El Osta, and Mathilde Jegoudez for their help in running experiments.

Notes

¹ We do not discuss in this article one specific type of phonological similarity that is the lists of words sharing the same rhyme (e.g., coin, joint, point). In contrast to the detrimental effect of phonological similarity, the performance in immediate recall is better with rhyming words lists. The fact that all the words of a list belong to the same category (e.g., the words ending by “oin”) seems to give a cue that facilitates their retrieval from memory (e.g., Fallon, Groves, & Tehan, 1999).