Switching in adults with aphasia

This research was supported by CLA PhD student dissertation award and Bryngleson funds from the Department of Speech‐Language‐Hearing Sciences at the University of Minnesota. The authors thank Minnesota Stroke Association, Fairview hospitals, Methodist hospital, North Memorial hospital, Julia M. Davis Speech‐Language‐Hearing Center, Sister Kenney Institute, United hospital, Abbot Northwestern hospital, Courage Center, Amherst H. Wilder Foundation, Lyngblomsten, Augustana Care, Yang Zhang, Edward Carney, Ben Munson, Miriam Krause, and Pradeep Ramanathan who helped with participant recruitment, stimuli recording, computer programs, and data analysis. Special thanks to stroke survivors and to Cindy Busch, Kathleen Miller, Lynne Conley, Gail Lommen, Sharon Spencer, and Heather Cummings.

Abstract

Background: Clinicians report that many adults with aphasia have difficulty in switching ideas and responses in a flexible manner. Switching requires the regulation of processes from current and previous tasks, and the ability to resist interference from previous tasks. Yet there is little research that documents switching after aphasia. Furthermore predicting, or knowing what is to come next, may facilitate flexible switching.

Aims: The purpose of this study was to compare the switching ability of adults with aphasia to matched controls when the rules changed and when adults knew how the change would occur (predicting).

Methods & Procedures: A total of 14 adults with mild or moderate aphasia and 14 matched healthy controls switched between Go/No‐go (GNG) rules with minimised linguistic and cognitive demands. To determine if adults with aphasia benefited from knowing what to expect, predictable and unpredictable conditions were created. Switch cost and number of omission and commission errors were the dependent variables.

Outcomes & Results: Adults with aphasia were slower, less accurate, and less likely to disregard the previous rule when switching from one rule to another than controls. Predictable and unpredictable switching influenced participants' performance to some extent.

Conclusions: These findings provide evidence of impaired reconfiguration and interference when adults with aphasia switch rules. These underlying processing deficits are discussed within a broader framework of cognitive flexibility. Future studies should investigate switching processes and their relationship with functional communication.

Keywords:

• Switching
• Reconfiguration
• Interference
• Go/No‐go
• Aphasia

Notes

This research was supported by CLA PhD student dissertation award and Bryngleson funds from the Department of Speech‐Language‐Hearing Sciences at the University of Minnesota. The authors thank Minnesota Stroke Association, Fairview hospitals, Methodist hospital, North Memorial hospital, Julia M. Davis Speech‐Language‐Hearing Center, Sister Kenney Institute, United hospital, Abbot Northwestern hospital, Courage Center, Amherst H. Wilder Foundation, Lyngblomsten, Augustana Care, Yang Zhang, Edward Carney, Ben Munson, Miriam Krause, and Pradeep Ramanathan who helped with participant recruitment, stimuli recording, computer programs, and data analysis. Special thanks to stroke survivors and to Cindy Busch, Kathleen Miller, Lynne Conley, Gail Lommen, Sharon Spencer, and Heather Cummings.

1. There was no covariate because there were no opportunities for commission errors in the detection task.