Massed sentence repetition training can augment and speed up recovery of speech production deficits in patients with chronic conduction aphasia receiving donepezil treatment

Abstract

Background: In the past two decades, single-case studies evaluated the effect of massed repetition training to improve speech production and short-term memory deficits in conduction aphasia (CA). Improvements were reported in treated language and memory domains with modest generalisation of gains to spontaneous speech or auditory comprehension. Although these results are encouraging, sentence repetition training has not been compared with distributed speech-language therapy, and no studies have examined the role of pharmacological interventions to enhance gains promoted by these behavioural interventions in CA.

Aims: The effects of massed sentence repetition therapy (MSRT) were compared to those of distributed speech-language therapy (DSLT) in measures of verbal output, short-term memory and repetition in patients with chronic post-stroke CA receiving treatment with the cholinesterase inhibitor donepezil (DP).

Methods and Procedures: Three patients with chronic CA aphasia associated to large left perisylvian infarctions participated in a 28-week open-label study combining DP with DSLT or MSRT. A within-patient design, with baselines across behaviours and a washout period was used. Patients were treated with DP (10 mg/day) combined first with DSLT (16 weeks, 40 hours) and after a washout period (4 weeks) with MSRT (8 weeks, 40 hours). Language functions were assessed with the Western Aphasia Battery and experimental repetition tasks prior to and after DSLT and MSRT.

Outcomes and Results: Both interventions improved performance in speech production tasks, but better improvements were found with DP-MSRT than with DP-DSLT. Larger treatment effects were found for DP-MSRT in comparison with baselines and DP-DSLT in repetition of word pairs and triplets, and novel and experimental sentences with generalisation of gains to aphasia severity, connected speech and non-treated control sentences.

Conclusions: Combined interventions with DP and two different aphasia therapies (DSLT and MSRT) significantly improved speech production deficits in CA, but DP-MSRT augmented and speeded up most benefits provided by DP-DSLT.

Keywords:

• Aphasia
• Conduction aphasia
• Aphasia therapy
• Pharmacotherapy
• Donepezil
• Experience-dependent plasticity.

The authors thank the patients for their cooperation during the study. This study has been supported by a grant from Pfizer and Eisai (Spain) to the corresponding author.

This paper has been presented in part in the Twenty-Sixth Annual International Neuropsychological Society Mid-Year Conference, 16–20 July 2003, Berlin and in the 56th Annual Meeting of the American Academy of Neurology, San Francisco, 24 April–1 May 2004.

Notes

¹ Melodic Intonation Therapy (MIT) is a rehabilitation technique commonly used to treat patients with non-fluent speech production and preserved comprehension (Broca’s aphasia) resulting from left hemisphere damage (Sparks et al., 1974). MIT engages relatively preserved functions (melody, rhythm and formulaic language) dependent upon right perisylvian white matter tracts and corticostriatal activity to improve verbal output and communication (Schlaug et al., 2009; Stahl, Henseler, Turner, Geyer, & Kotz, 2013; Zipse et al., 2012)

² Donepezil is a centrally acting reversible acetylcholinesterase inhibitor. It inhibits the enzyme (acetylcholinesterase) that breaks down acetylcholine in the synaptic cleft, thus increasing both the level and duration of action of endogenous acetylcholine. Although donepezil is only authorised for the treatment of Alzheimer’s disease, it has been tested (off label use) in other cognitive disorders, including vascular dementia and vascular and degenerative aphasias. Donepezil is safe and well-tolerated in patients with these disorders. Nonetheless, it should be used with caution in patients with cardiac conduction disturbances, chronic obstructive pulmonary disease, severe bronchial asthma, severe cardiac arrhythmias and sick sinus syndrome.

³ All statistical comparisons were performed using McNemar tests (two-tailed) unless specified.

⁴ Analysis of errors during word and sentence repetition at baselines (A₁ and A₂) and end points (BC and BD) will be reported elsewhere.