Visual working memory is enhanced by mixed strategy use and semantic coding

Abstract

Visual working memory is enhanced by processes related to verbalisation. However, the mechanism underlying this enhancement is unclear. Experiment 1 investigated the potential contribution of the phonological loop of working memory, by assessing the effects of articulatory suppression on two versions of the Visual Patterns Test—one low and one high in availability of verbal coding. The lack of interaction suggested that the phonological loop is not responsible; however, active use of combined verbal and visual strategies, as well as activated semantic knowledge, both appear to be related to increased capacity. Experiment 2 assessed the role of central executive resources. Because central executive suppression removed the benefit of the high verbal coding task version, central executive resources, assumed to relate to the temporary maintenance of multimodal codes in the episodic buffer, appear to underlie the benefit associated with verbalisation.

Keywords:

• Central executive
• Episodic buffer
• Semantic long-term memory
• Verbal coding
• Visual working memory
• Visuospatial

Acknowledgments

We thank Ruth Greenwood-Mears and Sharon McBride for their assistance with data collection in Experiment 1.