Rapid recovery from aphasia after infarction of Wernicke’s area

ABSTRACT

Background: Aphasia following infarction of Wernicke’s area typically resolves to some extent over time. The nature of this recovery process and its time course have not been characterised in detail, especially in the acute/subacute period.

Aims: The goal of this study was to document recovery after infarction of Wernicke’s area in detail in the first 3 months after stroke. Specifically, we aimed to address two questions about language recovery. First, which impaired language domains improve over time and which do not? Second, what is the time course of recovery?

Methods & Procedures: We used quantitative analysis of connected speech and a brief aphasia battery to document language recovery in two individuals with aphasia following infarction of the posterior superior temporal gyrus (STG). Speech samples were acquired daily between 2 and 16 days post stroke, and also at 1 month and 3 months. Speech samples were transcribed and coded using the CHAT system in order to quantify multiple language domains. A brief aphasia battery was also administered at a subset of five time points during the 3 months.

Outcomes & Results: Both patients showed substantial recovery of language function over this time period. Most, but not all, language domains showed improvements, including fluency, lexical access, phonological retrieval and encoding, and syntactic complexity. The time course of recovery was logarithmic, with the greatest gains taking place early in the course of recovery.

Conclusions: There is considerable potential for amelioration of language deficits when damage is relatively circumscribed to the posterior STG. Quantitative analysis of connected speech samples proved to be an effective, albeit time consuming, approach to tracking day-by-day recovery in the acute/subacute post-stroke period.

KEYWORDS:

• Stroke
• aphasia
• recovery
• connected speech
• Wernicke’s area

Acknowledgements

We thank Audrey Holland for her advice on collecting and analysing speech samples; Pélagie Beeson and Gayle DeDe for providing input on project design and constructive feedback on a draft of this manuscript; Grace Cheifetz, Jane Eustance, Lisa Gordon, Sara McDonald, and Kim Neely for rating motor speech characteristics of speech samples; Kindle Rising and Dana Eriksson for helpful discussions; three anonymous reviewers for their constructive feedback; and the patients for their participation in our research.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported in part by the National Institutes of Health (National Institute on Deafness and Other Communication Disorders): grant R01 DC013270.