Investigating the Influence of Local and Personal Common Ground on Memory for Conversation Using an Online Referential Communication Task

To maintain efficiency during conversation, interlocutors form and retrieve memory representations for the shared understanding or common ground that they have with their partner. Here, an online referential communication task (RCT) was used in two experiments to examine whether the strength and type of common ground between dyads influence their ability to form and recall referential labels for images. Results from both experiments show a significant association between the strength of common ground formed between dyads for images during the RCT and their verbatim-but not semantic-recall memory for image descriptions about a week later. Participants who generated the image descriptions during the RCT also showed superior verbatim and semantic recall memory performance. In Experiment 2, a group of friends with pre-existing personal common ground were significantly more efficient in their use of words to describe images during the RCT than a group of strangers without personal common ground. However, personal common ground did not lead to enhanced recall memory performance. Together, these findings provide evidence that individuals can remember some verbatim words and phrases from conversations, and partially support the theoretical notion that common ground and memory are intricately linked conversational processes. The null findings with regard to semantic recall memory suggest that the structured nature of the RCT may have constrained the types of memory representations that individuals formed during the interaction. Findings are discussed in relation to the multidimensional nature of common ground and the importance of developing more natural conversational tasks for future work. Public Significance Statement Results from the current studies suggest that our ability to recall exact words and phrases from our previous interactions with others is significantly enhanced when we form stronger agreement or common ground with our conversational partner about topics that we discuss. These findings also indicate that humans can, in some instances, remember exact words and phrases from their interactions 7 days later, despite not being told in advance that their memory will be tested.