Effects of visual‐manual tracking under dual‐task conditions on auditory language comprehension and story retelling in persons with aphasia

The authors gratefully acknowledge the helpful comments of two anonymous reviewers, the volume editor, programming support of Neil Szuminsky, and the funding of this project by the Veterans Administration Rehabilitation Research and Development Service, project #C3159R.

Abstract

Background: Two recent studies (McNeil et al., 2004, 2005) evaluated non‐brain‐injured (N‐BI) elderly persons' dual‐task performance on a story retell procedure (SRP) and a visual‐manual line‐tracking task. Results of both studies demonstrated a unidirectional cost whereby the difficulty of the language task had an effect on tracking performance; however, the difficulty of the tracking task had no effect on language comprehension as indexed by story retelling.

The authors gratefully acknowledge the helpful comments of two anonymous reviewers, the volume editor, programming support of Neil Szuminsky, and the funding of this project by the Veterans Administration Rehabilitation Research and Development Service, project #C3159R.

Aims: The specific aim of this investigation was to assess the effects of performing a concurrent visual‐manual tracking task on the comprehension of stories in persons with aphasia (PWA).

Methods & Procedures: The current study evaluated the performance trading in these tasks in PWA using similar dual‐task procedures as those employed in the McNeil et al (2004, 2005) studies. Specifically, two tracking difficulty levels were used to assess concurrent costs under a single difficulty level of the SRP.

Outcomes & Results: The results of this study replicate, in PWA, the null effect of tracking difficulty on story retell performance that was found in the two earlier studies in N‐BI elderly persons. Contrary to predictions, there was no significant effect of tracking difficulty on story retell performance. There was also no significant difference between story comprehension or visual manual‐tracking tasks performed alone or in the competing conditions.

Conclusions: The results of this study do not support the hypothesis that a deficit in allocating processing resources in PWA would result in a concurrent cost of tracking difficulty on story comprehension. The results are discussed relative to the limitations of the story retell procedure for indexing potential dual‐task effects and relative to the possible structure of the shared cognitive architecture used in these specific dual‐tasks.

Notes

The authors gratefully acknowledge the helpful comments of two anonymous reviewers, the volume editor, programming support of Neil Szuminsky, and the funding of this project by the Veterans Administration Rehabilitation Research and Development Service, project #C3159R.