The feasibility of improving discourse in people with aphasia through AAC: clinical and functional MRI correlates

ABSTRACT

Background:The theory of intersystemic reorganization, along with the ability of people with chronic aphasia to recover language function, suggests that a high-tech augmentative and alternative communication (AAC) device could be employed as a dual-purpose tool that simultaneously facilitates language recovery and compensates for deficits. To date, treatments based on intersystemic reorganization have focused on writing, drawing, and gesturing. Further, despite a movement to identify neural mechanisms that support intervention-related recovery, the neurobiological markers of AAC-induced changes have not been established.

Aims: The purpose of this study is twofold: (1) to examine the feasibility of providing a high-tech AAC treatment to people with chronic aphasia, with the goal of evoking changes in spoken language; and (2) to identify evidence of AAC-induced changes in brain activation.

Method and Procedures: We employed a pre- and post-treatment design with a control (usual care) group to observe the impact of an AAC treatment on aphasia severity and spoken discourse. Further, we used functional magnetic resonance imaging (fMRI) to examine associated neural reorganization.

Outcomes and Results: Compared to the usual care group, the AAC intervention trended toward larger treatment effects and resulted in a higher number of responders on behavioral outcomes. Both groups demonstrated a trend toward greater leftward lateralization of language functions via fMRI. Secondary analyses of responders to treatment revealed increased activation in visual processing regions, primarily for the AAC group.

Conclusions: This study provides preliminary guidance regarding how to implement AAC treatment in a manner that simultaneously facilitates language recovery across a variety of aphasia types and severity levels while compensating for residual deficits in people with chronic aphasia. Further, this work motivates continued efforts to unveil the role of AAC-based interventions in the aphasia recovery process and provides insight regarding the neurobiological mechanisms supporting AAC-induced language changes.

KEYWORDS:

• Aphasia
• augmentative and alternative communication
• fMRI
• cortical plasticity
• neuroimaging

Acknowledgments

We appreciate the participants for their time and effort; because of them, we have a better understanding of how augmentative and alternative (AAC) interventions can be used to stimulate post-stroke language recovery and cortical plasticity. We thank the MRI technologists at CCHMC as well as Terri Hollenkamp and Victoria (Tory) McKenna (of Rehab Resources, Inc.), Joe Collier, Devan Macke, Alexandra (Lexi) Perrault, Sarah Thaxton, Leah Baccus, Milon Volk, and Narae Hyun, for their enduring patience and assistance collecting fMRI data, providing treatment, and processing the large amounts of data, respectively. The CCTST also provided data management via Research Electronic Data Capture (REDCap) (UL1-RR026314), statistical resources, and mentoring for the lead author. We thank the training data for FIRST, particularly to David Kennedy at the CMA, and also to: Christian Haselgrove, Centre for Morphometric Analysis, Harvard; Bruce Fischl, Martinos Center for Biomedical Imaging, MGH; Janis Breeze and Jean Frazier, Child and Adolescent Neuropsychiatric Research Program, Cambridge Health Alliance; Larry Seidman and Jill Goldstein, Department of Psychiatry of Harvard Medical School; and Barry Kosofsky, Weill Cornell Medical Center.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental material

Supplemental data can be accessed here.

Additional information

Funding

The project described was supported by an Institutional Training Award (KL2) from the University of Cincinnati (UC) and Cincinnati Children’s Hospital Medical Center for Clinical & Translational Science & Training (CCTST) via the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, Grants [8 KL2 TR000078-05; 8 UL1 TR000077-05]. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH, UC, CCHMC, or the CCTST; KL2 [TR000078-05]; Junior T1 [UL1 TR000077-05].