Title

Pragmatic Language Abilities: Working Memory Influences on Mutual Information

Date of Completion

January 2011

Keywords

Language, Linguistics|Psychology, Developmental|Psychology, Clinical|Psychology, Cognitive

Degree

Ph.D.

Abstract

Pragmatic language impairments in autism spectrum disorders (ASD) likely reflect an individual's ability to monitor what information is mutually known in a conversation, termed "common ground" (Clark, 1992). Common ground impairments in ASD have not been well studied, and could reflect limitations in working memory (WM) in addition to Theory of Mind (ToM). This study explored common ground in 13 children with ASD and 21 typically-developing controls, ages 8-17. We tracked participants' eye movements while they engaged in a referential communication task in which some information was private (known only to the participant; a manipulation of ToM). As a manipulation of WM load, the amount of private information varied. Accuracy was high across groups (91%), and all participants were slower to integrate private than shared information; this main effect was greater during high WM loads. There was a trend for the ASD group to be more influenced by competing information. Specifically, unlike controls, the ASD showed no significant improvement for low relative to high WM loads. Across groups, ASD-like behaviors, spatial WM, ToM, and inhibitory control were related to task performance. In addition, performance was related to verbal WM in controls, but to language and IQ in the ASD group. Results show that WM influences common ground representation across groups, and that even minimal WM demands impact referential communication skills in ASD. When WM demands increased, controls (like participants with ASD) had difficulty incorporating perspective. Results are consistent with research suggesting that perspective-taking places significant demands on cognitive processes. ^