Aphasia therapy early after stroke: behavioural and neurophysiological changes in the acute and post-acute phases

Abstract

Background: There is reasonable evidence to suggest that speech and language therapy can be effective in the chronic stages of stroke recovery. However, the active ingredients remain unknown and several variables can influence therapy outcome, such as content, type, and amount of therapy. Neurophysiological measures, event-related brain potentials such as the N400 and P300, have shown to be sensitive markers of therapeutic effects. As a supplement to the usual behavioural evaluation methods, neurophysiological measures might help to further disentangle the effect of content, type, and/or amount of therapy. Aims: The present single case study aims to investigate the effect of language therapy by combining behavioural and neurophysiological outcome measures in a patient with aphasia during the acute and post-acute stage after stroke. By further subdividing the therapy period into different therapy blocks, possible influences of content, type, and/or amount of therapy are investigated. Methods & Procedures: RL is a 47-year-old man with a moderate non-fluent aphasia, who received three periods of therapy in the first fourmonths after his stroke. The initial evaluation moment occurred 10days post-stroke. First, he received an intensive language treatment of 30hr in 3weeks, which was followed by a conventional treatment of 30hr in 7weeks. Then, RL received a second, intensive language therapy of 30hr in 3weeks. This was followed by a period of 6months without any form of language treatment. Behavioural and neurophysiological measures were collected after every therapy and therapy-free period. The effect of therapy was examined by comparing the whole therapy period with the therapy-free period, without differentiating between the intensive and conventional treatment. In a second analysis, a comparison was made between the intensive therapy periods and the conventional therapy programme. Outcomes & Results: RL showed a general improvement on both behavioural and neurophysiological measures after the whole therapy period, which was preserved throughout the therapy-free period. Intensive treatment yielded better language outcomes as indicated by a behavioural and neurophysiological improvement in contrast with the behavioural deterioration of auditory discrimination of pseudowords and decline of the N400 neurophysiological marker, after the conventional therapy. Conclusions: The present study demonstrates the outcome of early language treatment after stroke in which intensity can play an important role. In addition, the use of neurophysiological outcome measures provides added value to the behavioural evaluations in the context of therapeutic follow-up

A Review on Treatment-Related Brain Changes in Aphasia

“…Third, each therapy investigated had to focus specifically on one, maximally two, linguistic domain(s): semantics, phonology, syntax, orthography, and/or melody/rhythm, to enable the identification of brain changes after training of these specific types of language processing (aim 1). For this reason, studies providing mixed conventional therapy (e.g., Aerts et al, 2015), intention treatment (e.g., Benjamin et al, 2014), action observation treatment (e.g., Gili et al, 2017), interventions on the activity/participation level, imitation therapy (e.g., Santhanam, Duncan, & Small, 2018), script training (e.g., Fridriksson, Hubbard, et al, 2012), or constraint-induced language therapy (e.g., McKinnon et al, 2017) were not considered. We also excluded studies that combined language therapy with noninvasive brain stimulation and/or drug trials, intervention studies in bilingual aphasia, non-peer-reviewed reports, and studies that were not available in English.…”

Understanding Language Reorganization With Neuroimaging: How Language Adapts to Different Focal Lesions and Insights Into Clinical Applications

“…The study found that rehabilitation in the early phases is correlated with increased recruitment of left IFG on tb-fMRI, which lasted over time and improved object naming (Mattioli et al, 2014). A singlecase study reported the beneficial role of early therapeutic intervention by monitoring event-related potentials (ERPs) at electroencephalography (EEG), which have been proven to be useful in monitoring language abilities in aphasia patients (Aerts et al, 2015). Other recent clinical studies showed no deficit improvement after early aphasia treatment (Coleman et al, 2017;Nouwens et al, 2017).…”

Using functional imaging to understand therapeutic effects in poststroke aphasia

“…In a single-case study design, Aerts et al followed the effects of 90 hours of speech therapy (that included elements of auditory training) on a patient with acute, global aphasia using EEG [3]. As the therapy started on day 10 post-stroke and finished on day 105 it was no surprise that many of his language measures improved.…”