Treating apraxia of speech with an implicit protocol that activates speech motor areas via inner speech

Speech Therapy Interventions for Acquired Apraxia of Speech: An Updated Systematic Review

PURPOSE

This systematic review aims to summarize and evaluate the available literature on speech and language therapy interventions for acquired apraxia of speech since 2012.

METHOD

A systematic search in six electronic databases was performed from 2013 to 2020. The following primary outcomes were summarized: (a) improvement in targeted behaviors, (b) generalization, and (c) maintenance of outcomes. Moreover, studies were evaluated for the level of evidence and the clinical phase.

RESULTS

Of the 3,070 records identified, 27 studies were included in this review. The majority of the studies (n = 22) used articulatory kinematic approaches followed by intersystemic facilitation/reorganization treatments (n = 4) and other approaches (n = 1). According to the classes defined in Clinical Practice Guideline Process Manual (Gronseth et al., 2017), one was Class II, 10 were Class III, 10 were Class III-b (fulfill Class III criteria except for independence of assessors' criterion), and five were Class IV. In terms of clinical phase, one study classified as Phase III, 10 as Phase II, and 15 as Phase I.

CONCLUSIONS

Among the interventions for apraxia of speech, articulatory kinematic treatments have become prominent over the last 8 years. Focusing on self-administrated therapies, use of technology for therapy administration and development of treatments that focus on apraxia of speech and aphasia simultaneously were identified as new advancements in the apraxia of speech literature. The methodological quality, clinical phase, and level of evidence of the studies have improved within the past 8 years. Large-scale randomized controlled trials for articulatory kinematic approaches and future studies on other treatment approaches are warranted.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22223785.

Reliability of single-subject neural activation patterns in speech production tasks

Speech neuroimaging research targeting individual speakers could help elucidate differences that may be crucial to understanding speech disorders. However, this research necessitates reliable brain activation across multiple speech production sessions. In the present study, we evaluated the reliability of speech-related brain activity measured by functional magnetic resonance imaging data from twenty neuro-typical subjects who participated in two experiments involving reading aloud simple speech stimuli. Using traditional methods like the Dice and intraclass correlation coefficients, we found that most individuals displayed moderate to high reliability. We also found that a novel machine-learning subject classifier could identify these individuals by their speech activation patterns with 97% accuracy from among a dataset of seventy-five subjects. These results suggest that single-subject speech research would yield valid results and that investigations into the reliability of speech activation in people with speech disorders are warranted.

Inner Speech in Aphasia: Current Evidence, Clinical Implications, and Future Directions

Purpose Typical language users can engage in a lively internal monologue for introspection and task performance, but what is the nature of inner speech among individuals with aphasia? Studying the phenomenon of inner speech in this population has the potential to further our understanding of inner speech more generally, help clarify the subjective experience of those with aphasia, and inform clinical practice. In this scoping review, we describe and synthesize the existing literature on inner speech in aphasia. Method Studies examining inner speech in aphasia were located through electronic databases and citation searches. Across the various studies, methods include both subjective approaches (i.e., asking individuals with aphasia about the integrity of their inner speech) and objective approaches (i.e., administering objective language tests as proxy measures for inner speech ability). The findings of relevant studies are summarized. Results Although definitions of inner speech vary across research groups, studies using both subjective and objective methods have established findings showing that inner speech can be preserved relative to spoken language in individuals with aphasia, particularly among those with relatively intact word retrieval and difficulty primarily at the level of speech output processing. Approaches that combine self-report with objective measures have demonstrated that individuals with aphasia are, on the whole, reliably able to report the integrity of their inner speech. Conclusions The examination of inner speech in individuals with aphasia has potential implications for clinical practice, in that differences in the preservation of inner speech across individuals may help guide clinical decision making around aphasia treatment. Although there are many questions that remain open to further investigation, studying inner speech in this specific population has also contributed to a broader understanding of the mechanisms of inner speech more generally.