Aphasia is an acquired language disorder affecting two million in the USA. Currently, a major obstacle in the field lies in understanding cognitive mechanisms that predict treated language recovery in persons living with aphasia and those mechanisms that promote living well with aphasia – that is, fostering personal and participatory outcomes, like social relationships and sense of self. In this project, we directly evaluate a single cognitive-linguistic mechanism that has been discussed across several disciplines for the better part of a century, but has received little focus in its role in aphasia recovery: inner speech. Indeed, persons living with aphasia often endorse ‘knowing what they want to say but not being able to say it.’ Innovatively, we bring an interdisciplinary view to our evaluation of inner speech, drawing from work across philosophy, psychology, neuroscience and communication sciences and disorders to characterize inner speech as an entity with at least two components: an expanded component (our self-generated internal dialogue) and a reduced component (our internal manipulation of phonological units). We postulate that each of these inner speech parts plays a role in aphasia recovery, and we propose two unique experiments (projects) to test this theory.
First, as no other group has attempted to characterize expanded inner speech in aphasia, we propose a mixed method inquiry to establish a reliable means of measuring expanded inner speech and its uses in persons living with aphasia. This will allow us to explore the role of expanded speech in recovery from aphasia in future work. Second, we systematically explore the role of reduced inner speech pre-therapy in predicting language outcomes after behavioral (speech-language) therapy using a multiple single subject design, thereby advancing our understanding of the importance of this cognitive-linguistic mechanism in aphasia recovery.
The goal of this project is to characterize and identify the role of inner speech across recovery domains (e.g., personal, linguistic), preparing a strong foundation on which future work will build. Altogether, this work has ramifications for improving prognostication (i.e., prognosis of aphasia recovery, and factors that help predict recovery), and quality of life of persons living with aphasia.