The impact of dose on naming accuracy with persons with aphasia

Abstract

Background: Although aphasia rehabilitation has been shown to be efficacious, many questions remain regarding how best to deliver treatment to maximise functional gains for persons with aphasia. Treatment-delivery variables, such as intensity and dosage, are likely to influence both behavioural and structural changes during anomia treatment. While numerous protocols have concluded that treatment intensity positively impacts functional outcomes, few studies to date have examined the role that dose plays in patient outcomes for anomia treatment.

Aims: This study sought to investigate how manipulating dose of repeated confrontation naming within sessions influences naming in persons with aphasia. Repeated practice of confrontation naming, without feedback, was hypothesised to improve trained but not untrained words, to be persistent after withdrawal, and to be sensitive to the number of trials (i.e., dose) within sessions.

Methods and Procedures: A single-subject ABA design, with replication across seven participants with aphasia, was used to investigate the influence of repeated confrontation naming attempts on the acquisition and maintenance of trained pictures relative to untrained pictures. Training involved repeated attempts to name pictures, along with repeated exposure to pictures of objects (nouns) and their names, without feedback. The primary independent variable was within session dose; the dependent variable was naming accuracy.

Outcomes and Results: Naming accuracy improved for all participants for trained pictures across both acquisition and maintenance phases per visual inspection; such positive effects were not observed for untrained pictures. Effect-size calculations indicate that three of seven participants demonstrated considerable change for trained items, while one of seven participants demonstrated meaningful change for untrained items. The high-dose condition elicited small effect sizes for one participant, and large effect sizes for two of seven participants, while the low-dose condition elicited small and medium effect sizes for two of seven participants.

Conclusions: Participants across a variety of aphasia severity levels responded positively to two doses of repeated confrontation naming practice, without feedback, across phases of this naming protocol. Results are in line with principles of neuroplasticity and demonstrate that repeated practice, without feedback, can produce significant and persistent changes in naming ability for some persons with aphasia.

Keywords:

• aphasia
• anomia
• picture naming
• dose
• intensity
• repetition priming

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the University of Montana Small Grant Program [grant number #MRA797]; and the National Institutes of Health Ruth L. Kirschstein National Research Service Award [Training Grant number #5T32DC00033-14]. A portion of the data presented in this manuscript was published as a doctoral dissertation under the mentorship and guidance of Dr. Margaret Rogers and Dr. Kristie Spencer.