Ultra-rapid access to words in chronic aphasia: the effects of intensive language action therapy (ILAT)

Auditory Comprehension Interventions for People With Aphasia: A Scoping Review

PURPOSE

This scoping review examined studies reporting restorative treatments designed to improve auditory comprehension in people with aphasia.

METHOD

We searched eight databases using keywords aphasia, auditory comprehension, treatment, intervention, and rehabilitation, for studies published between 1970 and 2020. Searches returned 170 records, and after applying exclusionary criteria, 28 articles remained. For each article, two authors independently extracted data on study design parameters, participant characteristics, treatment protocol, and treatment outcomes, including generalization.

RESULTS

Studies were categorized by treatment focus: direct auditory (n = 7), mixed auditory (n = 13), or indirect (n = 8). Study designs were group (n = 12), single-subject experimental design (n = 11), or case study (n = 5). Fifteen studies had a control condition and/or a control group. Thirteen studies included two to 10 participants. Aphasia severity and auditory comprehension severity were infrequently reported, and most participants were greater than 1-year poststroke. Treatment targets and tasks varied. Sessions ranged from 8 to 240 min, once or more per week, for eight to 60 total sessions over 2-20 weeks. Impairment-based outcome measures were typically used. Improvement and generalization were regularly reported; however, authors frequently did not report statistical significance.

CONCLUSIONS

A variety of treatments have addressed auditory comprehension deficits in people with aphasia, with many reporting improvements in auditory comprehension for some people. However, the variability in treatment tasks and delivery and outcome measurements preclude confidently offering specific clinical recommendations for implementing auditory comprehension treatments. Gaps identified by the current study may guide the development and exploration of transparent, repeatable, patient-centered treatments.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21291345.

Kinesthetic motor-imagery training improves performance on lexical-semantic access

The objective of this study was to evaluate the effect of Motor Imagery (MI) training on language comprehension. In line with literature suggesting an intimate relationship between the language and the motor system, we proposed that a MI-training could improve language comprehension by facilitating lexico-semantic access. In two experiments, participants were assigned to a kinesthetic motor-imagery training (KMI) group, in which they had to imagine making upper-limb movements, or to a static visual imagery training (SVI) group, in which they had to mentally visualize pictures of landscapes. Differential impacts of both training protocols on two different language comprehension tasks (i.e., semantic categorization and sentence-picture matching task) were investigated. Experiment 1 showed that KMI training can induce better performance (shorter reaction times) than SVI training for the two language comprehension tasks, thus suggesting that a KMI-based motor activation can facilitate lexico-semantic access after only one training session. Experiment 2 aimed at replicating these results using a pre/post-training language assessment and a longer training period (four training sessions spread over four days). Although the improvement magnitude between pre- and post-training sessions was greater in the KMI group than in the SVI one on the semantic categorization task, the sentence-picture matching task tended to provide an opposite pattern of results. Overall, this series of experiments highlights for the first time that motor imagery can contribute to the improvement of lexical-semantic processing and could open new avenues on rehabilitation methods for language deficits.

Native language experience shapes pre-attentive foreign tone processing and guides rapid memory trace build-up: An ERP study

Language experience, particularly from our native language (L1), shapes our perception of other languages around us. The present study examined how L1 experience moulds the initial processing of foreign (L2) tone during acquisition. In particular, we investigated whether learners were able to rapidly forge new neural memory traces for novel tonal words, which was tracked by recording learners’ ERP responses during two word acquisition sessions. We manipulated the degree of L1–L2 familiarity by comparing learners with a nontonal L1 (German) and a tonal L1 (Swedish) and by using tones that were similar (fall) or dissimilar (high, low, rise) to those occurring in Swedish. Our results indicate that a rapid, pre‐attentive memory trace build‐up for tone manifests in an early ERP component at ~50 ms but only at particularly high levels of L1–L2 similarity. Specifically, early processing was facilitated for an L2 tone that had a familiar pitch shape (fall) and word‐level function (inflection). This underlines the importance of these L1 properties for the early processing of L2 tone. In comparison, a later anterior negativity related to the processing of the tones’ grammatical content was unaffected by native language experience but was instead influenced by lexicality, pitch prominence, entrenchment, and successful learning. Behaviorally, learning effects emerged for all learners and tone types, regardless of L1–L2 familiarity or pitch prominence. Together, the findings suggest that while L1‐based facilitation effects occur, they mainly affect early processing stages and do not necessarily result in more successful L2 acquisition at behavioral level.

Our findings add important evidence that contributes to answering the open question of how similarity between native and target language influences target language processing and acquisition. We found facilitative effects of similarity only at pre‐attentive levels and only when the degree of similarity was high. Late processing and successful acquisition, on the other hand, were unaffected by the target words’ similarity to native language properties.

Is Aphasia Treatment Beneficial for the Elderly? A Review of Recent Evidence

Purpose

We review recent literature regarding aphasia therapy in the elderly. Relevant articles from the last 5 years were identified to determine whether or not there is evidence to support that various therapeutic approaches can have a positive effect on post-stroke aphasia in the elderly.

Recent findings

There were no studies examining the effects of aphasia therapy specifically in the elderly within the timeframe searched. Therefore, we briefly summarize findings from 50 relevant studies that included large proportions of participants with post-stroke aphasia above the age of 65. A variety of behavioral and neuromodulation therapies are reported.

Summary

We found ample evidence suggesting that a variety of behavioral and neuromodulatory therapeutic approaches can benefit elderly individuals with post-stroke aphasia.

The sensitivity of event-related potentials/fields to logopedic interventions in patients with stroke-related aphasia

Recovery of stroke-related aphasia can be affected by language therapy in the early and chronic stage. Objectively monitoring therapy-induced neuroplasticity is possible by several measurement techniques including electro- and magneto-encephalography. The obtained event-related potentials (ERPs) and fields (ERFs) provide insights into the neural basis of intact or deficient language processing with milliseconds precision. In this literature review, we highlight the sensitivity of ERPs and ERFs to logopedic interventions by providing an overview of therapy-induced changes in the amplitude, latency and topography of early and mid-to-late components.

Benchmarks of Significant Change After Aphasia Rehabilitation

OBJECTIVE

To establish benchmarks of significant change for aphasia rehabilitation outcome measures (ie, Western Aphasia Battery-Aphasia Quotient [WAB-AQ], Communicative Effectiveness Index [CETI], Boston Naming Test [BNT]) and assess if those benchmarks significantly differ across subgroups (ie, time post onset, dose frequency, treatment type).

DATA SOURCES

A comprehensive literature search of 12 databases, reference lists of previous reviews, and evidence-based practice materials was conducted.

STUDY SELECTION

Randomized controlled trials, quasi-experimental studies, single-subject design, and case studies that used a standardized outcome measure to assess change were included. Titles and full-text articles were screened using a dual review process. Seventy-eight studies met criteria for inclusion.

DATA EXTRACTION

Data were extracted independently, and 25% of extractions were checked for reliability. All included studies were assigned quality indicator ratings and an evidence level.

DATA SYNTHESIS

Random-effects meta-analyses were conducted separately for each study design group (ie, within-/between-group comparisons). For within-group designs, the summary effect size after aphasia rehabilitation was 5.03 points (95% confidence interval, 3.95-6.10, P<.001) on the WAB-AQ, 10.37 points (6.08-14.66, P<.001) on the CETI, and 3.30 points (2.43-4.18, P<.001) on the BNT. For between-group designs, the summary effect size was 5.05 points (1.64-8.46, P=.004) on the WAB-AQ and 0.55 points (-1.33 to 2.43, P=.564) on the BNT, the latter of which was not significant. Subgroup analyses for the within-group designs showed no significant differences in the summary effect size as a function of dose frequency or treatment type.

CONCLUSIONS

This study established benchmarks of significant change on 3 standardized outcome measures used in aphasia rehabilitation.

Therapist-Guided Tablet-Based Telerehabilitation for Patients With Aphasia: Proof-of-Concept and Usability Study

BACKGROUND

Aphasia is the loss or impairment of language functions and affects everyday social life. The disorder leads to the inability to understand and be understood in both written and verbal communication and affects the linguistic modalities of auditory comprehension, verbal expression, reading, and writing. Due to heterogeneity of the impairment, therapy must be adapted individually and dynamically to patient needs. An important factor for successful aphasia therapy is dose and intensity of therapy. Tablet computer-based apps are a promising treatment method that allows patients to train independently at home, is well accepted, and is known to be beneficial for patients. In addition, it has been shown to ease the burden of therapists.

OBJECTIVE

The aim of this project was to develop an adaptive multimodal system that enables aphasic patients to train at home using language-related tasks autonomously, allows therapists to remotely assign individualized tasks in an easy and time-efficient manner, and tracks the patient's progress as well as creation of new individual exercises.

METHODS

The system consists of two main parts: (1) the patient's interface, which allows the patient to exercise, and (2) the therapist's interface, which allows the therapist to assign new exercises to the patient and supervise the patient's progress. The pool of exercises is based on a hierarchical language structure. Using questionnaires, therapists and patients evaluated the system in terms of usability (ie, System Usability Scale) and motivation (ie, adapted Intrinsic Motivation Inventory).

RESULTS

A total of 11 speech and language therapists (age: mean 28, SD 7 years) and 15 patients (age: mean 53, SD 10 years) diagnosed with aphasia participated in this study. Patients rated the Bern Aphasia App in terms of usability (scale 0-100) as excellent (score >70; Z=-1.90; P=.03) and therapists rated the app as good (score >85; Z=-1.75; P=.04). Furthermore, patients enjoyed (scale 0-6) solving the exercises (score>3; mean 3.5, SD 0.40; Z=-1.66; P=.049).

CONCLUSIONS

Based on the questionnaire scores, the system is well accepted and simple to use for patients and therapists. Furthermore, the new tablet computer-based app and the hierarchical language exercise structure allow patients with different types of aphasia to train with different doses and intensities independently at home. Thus, the novel system has potential for treatment of patients with aphasia as a supplement to face-to-face therapy.

Therapy-Induced Neuroplasticity of Language in Chronic Post Stroke Aphasia: A Mismatch Negativity Study of (A)Grammatical and Meaningful/less Mini-Constructions

Clinical language performance and neurophysiological correlates of language processing were measured before and after intensive language therapy in patients with chronic (time post stroke >1 year) post stroke aphasia (PSA). As event-related potential (ERP) measure, the mismatch negativity (MMN) was recorded in a distracted oddball paradigm to short spoken sentences. Critical 'deviant' sentence stimuli where either well-formed and meaningful, or syntactically, or lexico-semantically incorrect. After 4 weeks of speech-language therapy (SLT) delivered with high intensity (10.5 h per week), clinical language assessment with the Aachen Aphasia Test battery demonstrated significant linguistic improvements, which were accompanied by enhanced MMN responses. More specifically, MMN amplitudes to grammatically correct and meaningful mini-constructions and to 'jabberwocky' sentences containing a pseudoword significantly increased after therapy. However, no therapy-related changes in MMN responses to syntactically incorrect strings including agreement violations were observed. While MMN increases to well-formed meaningful strings can be explained both at the word and construction levels, the neuroplastic change seen for 'jabberwocky' sentences suggests an explanation in terms of constructions. The results confirm previous reports that intensive SLT leads to improvements of linguistic skills in chronic aphasia patients and now demonstrate that this clinical improvement is associated with enhanced automatic brain indexes of construction processing, although no comparable change is present for ungrammatical strings. Furthermore, the data confirm that the language-induced MMN is a useful tool to map functional language recovery in PSA.

Near-instant automatic access to visually presented words in the human neocortex: neuromagnetic evidence

Rapid and efficient processing of external information by the brain is vital to survival in a highly dynamic environment. The key channel humans use to exchange information is language, but the neural underpinnings of its processing are still not fully understood. We investigated the spatio-temporal dynamics of neural access to word representations in the brain by scrutinising the brain's activity elicited in response to psycholinguistically, visually and phonologically matched groups of familiar words and meaningless pseudowords. Stimuli were briefly presented on the visual-field periphery to experimental participants whose attention was occupied with a non-linguistic visual feature-detection task. The neural activation elicited by these unattended orthographic stimuli was recorded using multi-channel whole-head magnetoencephalography, and the timecourse of lexically-specific neuromagnetic responses was assessed in sensor space as well as at the level of cortical sources, estimated using individual MR-based distributed source reconstruction. Our results demonstrate a neocortical signature of automatic near-instant access to word representations in the brain: activity in the perisylvian language network characterised by specific activation enhancement for familiar words, starting as early as ~70 ms after the onset of unattended word stimuli and underpinned by temporal and inferior-frontal cortices.