Exploring the mechanism of imageability effect in verbal short-term memory

Abstract

This study focuses on the role of phonological and lexico-semantic knowledge in auditory verbal attention, and tries to tackle the specific question of the mechanism behind the imageability effect in verbal short-term memory (STM). We look into the impact of explicit instruction of strategy (semantic and phonological) on imageability effect in serial verbal STM task.

Two groups of participants were formed: a semantic strategy group instructed to focus on the meaning of the words and perform mental imagery, a phonological strategy group instructed to focus on the sound of the words and engage in articulatory rehearsal. Our results shown strong imageability effect in both groups. No interaction of imageability effect and strategy instruction was found.

We discuss our results by casting doubt on whether strategy could be reliably induced by strategy instruction. Because the attentional demand of maintenance strategy could possibly affect its application in a STM task. Our results are in favor of an automatic semantic coding but we insist the participation of attentional control in semantic coding when the to-be-remembered information is in conflict with the stored semantic knowledge (Hoffman, Jefferies, Ehsan, Jones, & Lambon Ralph, 2012).

Finally, further study needs to apply a more objective strategy control measure to assess the participant's strategy behavior.