An enhanced protocol for constraint-induced aphasia therapy II: a case series

Therapies and Challenges in the Post-Stroke Aphasia Rehabilitation Arena: Current and Future Prospects

Aphasia is a serious consequence of stroke that results in a breakdown in communication. The course of aphasia recovery differs between afflicted individuals, and responsiveness to treatment cannot be predicted. Aphasiologists continue to investigate numerous behavioral treatment protocols that have shifted their focus to complimentary rehabilitation strategies. The aim of this study is threefold. First, to summarize the different categories of aphasia interventions post-stroke, considering their respective protocols, and present available evidence on the effectiveness of those protocols. Second, to document the challenges regarding the prediction of aphasia treatment response post-stroke in individual patients. Third, to report the challenges faced by researchers in recruiting people with aphasia (PWA) for treatment studies, and provide recommendations on how to increase participant recruitment and retention. This study provides up-to-date information on (i) effective therapies and aphasia recovery processes, and (ii) research recruitment hurdles together with potential strategies for overcoming them.

Motivation Theory and Practice in Aphasia Rehabilitation: A Scoping Review

PURPOSE

In the aphasia literature, motivation has been described as potentially influencing rehabilitation outcomes, and there are reports that researchers and clinicians have acted to promote it. However, studies directly investigating the range of beliefs and practices surrounding motivation do not exist currently. The purpose of this scoping review is to develop themes related to the beliefs and practices appearing in the recent aphasia literature.

METHOD

Four databases (CINAHL, PsycINFO, PubMed, and Google Scholar) were searched using keywords aphasia and motivation (including derivatives such as motiv*) for articles published between 2009 and 2020. Searches returned 19,731 articles; after deleting duplicates and applying inclusionary criteria, 365 articles remained. In each article, text surrounding the term motivation was highlighted and thematic analysis was applied to these quotations.

RESULTS

Sixteen themes were developed through thematic analysis and placed into two groups. The first group contained five themes suggesting that researchers believed that motivation should be studied and recognized the value of motivation in person(s) with aphasia when participating in research or clinical activities. The second group contained 11 themes reporting diverse beliefs and practices in how motivation is incorporated in research and clinical activities.

CONCLUSIONS

Results from this scoping review suggest that aphasia researchers, clinicians, and persons with aphasia hold beliefs about motivation that can influence clinical and research decisions. In general, beliefs and decisions related to motivation appeared to be guided by intuition rather than theories of motivation. These themes are discussed within the context of three psychological needs proposed by self-determination theory: competency, autonomy, and relatedness. Applying theories of motivation to future study in aphasia rehabilitation will guide work that can provide empirical support for these beliefs.

The Mechanism and Clinical Application of Constraint-Induced Movement Therapy in Stroke Rehabilitation

Constraint-induced movement therapy (CIMT) has been widely applied in stroke rehabilitation, and most relevant studies have shown that CIMT helps improve patients' motor function. In practice, however, principal issues include inconsistent immobilization durations and methods, while incidental issues include a narrow application scope and an emotional impact. Although many studies have explored the possible internal mechanisms of CIMT, a mainstream understanding has not been established.

Acceptability of constraint induced movement therapy: influence of perceived difficulty and expected treatment outcome

BACKGROUND

Constraint-Induced Movement (CI) Therapy has evidence of efficaciously rehabilitating upper-extremity hemiparesis after stroke. Yet, it is not widely used in the United States. One barrier appears to be the perception of its difficulty among stroke care consumers, as reported by two published studies in which the participants had little or no apparent direct exposure to CI Therapy.

OBJECTIVES

Assess the perception of difficulty of CI Therapy by individuals with chronic stroke who have actually undergone CI Therapy.

METHODS

A secondary analysis was conducted of data from two randomized controlled trials of CI Therapy. Participants had chronic, mild-to-moderate upper-extremity hemiparesis after stroke. The Motor Activity Log and Wolf Motor Function Test were used to measure motor function of the more-affected arm. A Patient Opinion Survey assessed participants' perception of difficulty and satisfaction with treatment.

RESULTS

The participants (N = 40) showed large improvements in motor function of their more-affected arm after treatment, p's <001. CI Therapy was perceived to be of only moderate difficulty by participants before treatment (mean = 4.4 out of 7). Perception of its difficulty decreased afterward (mean = 3.7, p = .002). Moreover, participants were highly satisfied with their outcomes (mean = 6.3 out of 7). Satisfaction was positively related to the improvements in more-affected arm use in everyday life, ΔR² = .3, p < .001.

CONCLUSIONS

Chronic stroke survivors who have actually had CI Therapy perceive it to be of only moderate difficulty and are highly satisfied. Negative views about its acceptability warrant reconsideration.

A systematic review of maintenance following intensive therapy programs in chronic post-stroke aphasia: importance of individual response analysis

PURPOSE

Recent evidence supports the benefit of intensive aphasia intervention programs for people with chronic aphasia, yet it is unclear if all participants can expect positive outcomes and for how long therapeutic gains last.

METHODS

We systematically searched for studies investigating intensive interventions in chronic aphasia. To explore individual response rates and maintenance of therapeutic gains we carried out meta-synthesis by calculating and analysing the Standard Error of Measurement and Minimal Detectable Change metrics of six common outcome measures.

RESULTS

Forty-four studies comprising 24 experimental (13 group, 11 single-subject) and 20 non-experimental studies met our inclusion criteria (n = 670). Whereas most group studies reported statistically significant post-therapy improvement and maintenance, analysis of individual participant data (IPD, n = 393) from these studies revealed that only about a third of participants were classified as "immediate responders," of which more than a third had lost their initial immediate gains at follow-up. This pattern did not change when IPD from single-subject studies (n = 49) was added to the analysis. Thus, only 22% of all IPD receiving an intensive intervention improved significantly and maintained their therapy gains.

CONCLUSIONS

Intensive aphasia therapy is effective when measured at the group-level, but many individuals do not respond significantly to the intervention, and even fewer individuals preserve their initial gains. Group study results do not allow prediction of an individual's response to the intervention. Future research should elucidate which factors mediate positive treatment response and maintenance for an individual.Implications for rehabilitationOnly a small proportion (about one fifth in this review) of intensive aphasia treatment program participants respond and maintain their therapy gains, a fact that is obscured by traditional p-value group analysis.A simple clinical decision-making method is presented for evaluating individual therapy gains and their maintenance.For some immediate treatment responders (about one third in this review), gains from intensive therapy programs are unlikely to be maintained in the long-term without additional, ongoing practice.Clinicians should consider the possibility of individual clients losing some of their therapy gains and take proactive steps to support long-term maintenance.

Reliability and Validity of the Lower Extremity Motor Activity Log for Measuring Real-World Leg Use in Adults With Multiple Sclerosis

OBJECTIVES

To determine the test-retest reliability and validity of the Lower Extremity Motor Activity Log (LE-MAL) for assessing LE use in the community in adults with multiple sclerosis (MS).

DESIGN

Prospective analysis of measures conducted by trained examiners.

SETTING

Participants were evaluated by telephone on several measures of LE use.

PARTICIPANTS

Adults with MS (N=43).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The LE-MAL has 3 subscales (Assistance, Functional Performance, and Confidence). It was administered twice, at least 2 weeks apart. The Multiple Sclerosis Walking Scale (MSWS-12), Patient Determined Disease Steps (PDDS), and Mobility Scale were only administered during the first call.

RESULTS

The test-retest reliability of the composite and the 3 subscale LE-MAL scores were high (intraclass correlation, >0.94). The composite and subscale LE-MAL scores were strongly correlated with the MSWS-12, PDDS, and Mobility Scale scores (r=-0.56 to -0.77; P<.001).

CONCLUSION

This initial study suggests that the LE-MAL reliably and validly measures LE use in the community in adults with MS.

The Role of Gesture in Communication and Cognition: Implications for Understanding and Treating Neurogenic Communication Disorders

When people talk, they gesture. Gesture is a fundamental component of language that contributes meaningful and unique information to a spoken message and reflects the speaker's underlying knowledge and experiences. Theoretical perspectives of speech and gesture propose that they share a common conceptual origin and have a tightly integrated relationship, overlapping in time, meaning, and function to enrich the communicative context. We review a robust literature from the field of psychology documenting the benefits of gesture for communication for both speakers and listeners, as well as its important cognitive functions for organizing spoken language, and facilitating problem-solving, learning, and memory. Despite this evidence, gesture has been relatively understudied in populations with neurogenic communication disorders. While few studies have examined the rehabilitative potential of gesture in these populations, others have ignored gesture entirely or even discouraged its use. We review the literature characterizing gesture production and its role in intervention for people with aphasia, as well as describe the much sparser literature on gesture in cognitive communication disorders including right hemisphere damage, traumatic brain injury, and Alzheimer's disease. The neuroanatomical and behavioral profiles of these patient populations provide a unique opportunity to test theories of the relationship of speech and gesture and advance our understanding of their neural correlates. This review highlights several gaps in the field of communication disorders which may serve as a bridge for applying the psychological literature of gesture to the study of language disorders. Such future work would benefit from considering theoretical perspectives of gesture and using more rigorous and quantitative empirical methods in its approaches. We discuss implications for leveraging gesture to explore its untapped potential in understanding and rehabilitating neurogenic communication disorders.

Analysis of oral-nasal balance after intensive speech therapy combined with speech bulb in speakers with cleft palate and hypernasality

OBJECTIVE

To evaluate the efficacy of the combination of a speech bulb with an intensive speech therapy program in hypernasal participants with cleft palate.

METHODS

Twenty hypernasal speakers with cleft palate (12 females and 8 males, median age 28.45 years), who were wearing speech bulbs underwent an intensive speech therapy program of 45 sessions over 3 weeks. Three experienced speech-language pathologists rated the participants' speech recordings before and after intensive speech therapy, with and without the speech bulb. Nasometric recordings and long-term averaged spectra were also analyzed using repeated-measures ANOVAs.

RESULTS

The ANOVA of the hypernasality ratings showed significant effects of therapy [F (1,19) = 15.97; p < .001], speech bulb [F(1,190 = 28.54, p < .001] and a therapy -speech bulb interaction effect [F(1.19) = 22.30, p < 0.001]. The most favorable listener ratings of hypernasality were obtained post-therapy when participants were wearing their speech bulbs. Without the speech bulb, intensive speech therapy by itself did not result in a significant improvement. With speech bulb, nasalance scores for high [F (1,19) = 14.07, p < .001] and low pressure [F (1,19) = 14.84, p < .001] sentences were significantly lower post-therapy, providing preliminary evidence that an intensive speech therapy program may enhance the effect of a speech bulb. Before and after comparisons of individual nasalance profiles demonstrated variable improvement in 15 participants, no progress in 2 participants and more severe hypernasality after therapy in 3 participants. Long-term averaged spectra corroborated the findings of the perceptual analysis. Based on a frequency bin from 201 to 300 Hz, there was a significant within-subject effect for with and without speech bulb [F(1, 18) = 4.54, p = .047] as well as for before vs. after session [F (1,18) = 7.14, p = .015].

CONCLUSION

The speech bulb in combination with intensive speech therapy resulted in improved oral-nasal balance for the majority of participants. More research is needed to investigate long-term outcomes as well as individual factors contributing to therapy success.

Neuroplasticity of Language Networks in Aphasia: Advances, Updates, and Future Challenges

Researchers have sought to understand how language is processed in the brain, how brain damage affects language abilities, and what can be expected during the recovery period since the early 19th century. In this review, we first discuss mechanisms of damage and plasticity in the post-stroke brain, both in the acute and the chronic phase of recovery. We then review factors that are associated with recovery. First, we review organism intrinsic variables such as age, lesion volume and location and structural integrity that influence language recovery. Next, we review organism extrinsic factors such as treatment that influence language recovery. Here, we discuss recent advances in our understanding of language recovery and highlight recent work that emphasizes a network perspective of language recovery. Finally, we propose our interpretation of the principles of neuroplasticity, originally proposed by Kleim and Jones (1) in the context of extant literature in aphasia recovery and rehabilitation. Ultimately, we encourage researchers to propose sophisticated intervention studies that bring us closer to the goal of providing precision treatment for patients with aphasia and a better understanding of the neural mechanisms that underlie successful neuroplasticity.

Phase II Randomized Controlled Trial of Constraint-Induced Movement Therapy in Multiple Sclerosis. Part 2: Effect on White Matter Integrity

BACKGROUND

Constraint-induced movement therapy (CIMT) is a method of physical rehabilitation that has demonstrated clinical efficacy in patients with chronic stroke, cerebral palsy, and multiple sclerosis (MS).

OBJECTIVE

This pilot randomized controlled trial tested whether CIMT can also induce increases in white matter integrity in patients with MS.

METHODS

Twenty adults with chronic hemiparetic MS were randomized to receive either CIMT or complementary and alternative medicine (CAM) treatment (reported in the first article of this pair). Structural white matter change was assessed by tract-based spatial statistics (TBSS); measures included fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD).

RESULTS

CIMT and CAM groups did not differ in pretreatment disability or expectancy to benefit. As noted in the companion paper, the motor activity log (MAL) improved more after CIMT than CAM ( P < .001); the within-group effect size for CIMT was 3.7 (large d' = 0.57), while for CAM it was just 0.7. Improvements in white matter integrity followed CIMT and were observed in the contralateral corpus callosum (FA, P < .05), ipsilateral superior occipital gyrus (AD, P < .05), ipsilateral superior temporal gyrus (FA, P < .05), and contralateral corticospinal tract (MD and RD, P < .05).

CONCLUSION

CIMT produced a very large improvement in real-world limb use and induced white matter changes in patients with hemiparetic MS when compared with CAM. The findings suggest in preliminary fashion that the adverse changes in white matter integrity induced by MS might be reversed by CIMT.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT01081275).

Intensive Auditory Comprehension Treatment for Severe Aphasia: A Feasibility Study

BACKGROUND

Severe auditory comprehension impairments secondary to aphasia can adversely influence rehabilitative outcomes and quality of life. Studies examining intensive rehabilitative treatments for severe single-word auditory comprehension impairments are needed.

OBJECTIVES

Our purpose was to examine the feasibility and influence of a high-intensity word-picture verification treatment on high-frequency, word response accuracy. Research questions: (a) Can people with severe aphasia tolerate an intensive comprehension treatment? (b) Does an intensive intervention increase auditory comprehension response accuracy of spoken high-frequency words?

METHOD

This single-case ABA design study included 2 participants with chronic, severe auditory comprehension deficits secondary to stroke. A high-frequency, word-picture verification treatment was administered 2 hr/day, 5 days/week for 4 weeks and required participants to match the spoken word of the examiner to a picture representing an object.

RESULTS

Preliminary results suggest that some people with severe chronic aphasia can tolerate an intensive auditory comprehension treatment and demonstrate improvements in high-frequency, word-level response accuracy with large effect sizes suggesting generalization to untrained stimuli.

CONCLUSIONS

An intensive auditory comprehension treatment protocol can contribute to improvements in response accuracy for some people with severe aphasia. Larger sample size studies are needed to further examine the influence of intensity on improvements in auditory comprehension.

Treatment Response to a Double Administration of Constraint-Induced Language Therapy in Chronic Aphasia

Purpose

This study investigated changes in oral-verbal expressive language associated with improvements following 2 treatment periods of constraint-induced language therapy in 4 participants with stroke-induced chronic aphasia. Generalization of treatment to untrained materials and to discourse production was also analyzed, as was the durability of the treatment effect.

Method

Participants with aphasia were assessed using standardized measures and discourse tasks at 3 to 4 time points to document behavioral changes throughout each of two 30-hr treatment periods of constraint-induced language therapy. Daily probes of trained and untrained materials were also administered.

Results

Despite participant heterogeneity, behavioral results for each person with aphasia indicated a positive response to treatment following each treatment period indicated by performance on standardized tests, trained materials, or both. Treatment effects generalized to some degree to untrained stimuli and to discourse measures and were generally maintained at follow-up testing.

Conclusions

Data support the utility of a 2nd treatment period. Results are relevant to rehabilitation in chronic aphasia, confirming that significant language gains continue well past the point of spontaneous recovery and can occur in a relatively short time period. Importantly, changes are not confined to a single treatment period, suggesting that people with aphasia may benefit from multiple doses of high-intensity treatment.

Upper extremity motor training of a subject with initially motor complete chronic high tetraplegia using constraint-induced biofeedback therapy

Introduction

The purpose of this case study was to determine if a subject with chronic high tetraplegia (C3 AIS A) could learn to use an initially paralyzed upper extremity on the basis of training procedures alone.

Case presentation

Initially, an AIS examination revealed no purposive movement below the neck other than minimal shoulder movement. Training was carried out weekly over 39 months. Training began based on electromyographic biofeedback; the electrical activity of a muscle (biceps or triceps) was displayed visually on a computer monitor and the subject was encouraged to progressively increase the magnitude of the response in small increments on a trial-by-trial basis (i.e., shaping). When small, overt movements began to appear; these were, in turn, shaped so that their excursion progressively increased. Training then progressed to enable lifting the arm with the aid of the counterweight of a Swedish Help Arm. Mean movement excursions in the best session were: internal rotation 52.5 cm; external rotation 26.9 cm; shoulder extension 22.1 cm; shoulder flexion 15.2 cm; pronation/supination 120°; extension of index finger (D2) 2.5 cm. Movements were initially saltatory, becoming smoother over time. With the Swedish Help Arm, the subject was able to lift her hand an average of 24.3 cm in the best session with 0.7 kg counterweight acting at the wrist (1.9 J of work).

Discussion

Results suggest in preliminary fashion the effectiveness of this approach for improving upper extremity function after motor complete high tetraplegia. Thus, future studies are warranted. Possible mechanisms are discussed.

Constraint-induced aphasia therapy in post-stroke aphasia rehabilitation: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Constraint-induced aphasia therapy (CIAT) has been widely used in post-stroke aphasia rehabilitation. An increasing number of clinical controlled trials have investigated the efficacy of the CIAT for the post-stroke aphasia.

PURPOSE

To systematically review the randomized controlled trials (RCTs) concerning the effect of the CIAT in post-stroke patients with aphasia, and to identify the useful components of CIAT in post-stroke aphasia rehabilitation.

METHODS

A computerized database search was performed through five databases (Pubmed, EMbase, Medline, ScienceDirect and Cochrane library). Cochrane handbook domains were used to evaluate the methodological quality of the included RCTs.

RESULTS

Eight RCTs qualified in the inclusion criteria. Inconsistent results were found in comparing the CIAT with conventional therapies without any component from the CIAT based on the results of three RCTs. Five RCTs showed that the CIAT performed equally well as other intensive aphasia therapies, in terms of improving language performance. One RCT showed that therapies embedded with social interaction were likely to enhance the efficacy of the CIAT.

CONCLUSION

CIAT may be useful for improving chronic post-stroke aphasia, however, limited evidence to support its superiority to other aphasia therapies. Massed practice is likely to be a useful component of CIAT, while the role of "constraint" is needed to be further explored. CIAT embedded with social interaction may gain more benefits.

Neuroimaging Correlates of Post-Stroke Aphasia Rehabilitation in a Pilot Randomized Trial of Constraint-Induced Aphasia Therapy

Background

Recovery from post-stroke aphasia is a long and complex process with an uncertain outcome. Various interventions have been proposed to augment the recovery, including constraint-induced aphasia therapy (CIAT). CIAT has been applied to patients suffering from post-stroke aphasia in several unblinded studies to show mild-to-moderate linguistic gains. The aim of the present study was to evaluate the neuroimaging correlates of CIAT in patients with chronic aphasia related to left middle cerebral artery stroke.

Material/Methods

Out of 24 patients recruited in a pilot randomized blinded trial of CIAT, 19 patients received fMRI of language. Eleven of them received CIAT (trained) and eight served as a control group (untrained). Each patient participated in three fMRI sessions (before training, after training, and 3 months later) that included semantic decision and verb generation fMRI tasks, and a battery of language tests. Matching healthy control participants were also included (N=38; matching based on age, handedness, and sex).

Results

Language testing showed significantly improved performance on Boston Naming Test (BNT; p<0.001) in both stroke groups over time and fMRI showed differences in the distribution of the areas involved in language production between groups that were not present at baseline. Further, regression analysis with BNT indicated changes in brain regions correlated with behavioral performance (temporal gyrus, postcentral gyrus, precentral gyrus, thalamus, left middle and superior frontal gyri).

Conclusions

Overall, our results suggest the possibility of language-related cortical plasticity following stroke-induced aphasia with no specific effect from CIAT training.

Assessing the Amount of Spontaneous Real-World Spoken Language in Aphasia: Validation of Two Methods

PURPOSE

The purpose of this article is to present the results of a study evaluating the psychometric properties of 2 new measures that exclusively assess the amount of real-world spoken language in patients with aphasia.

METHOD

Forty individuals with aphasia were evaluated on several measures of spoken language in real-world settings. The Verbal Activity Log (VAL; Johnson et al., 2014) has participants, aided by caregivers, indicate current amount and quality of real-world spoken language compared with before stroke. In addition, digital voice recorders objectively measured the amount of real-world spoken language. The Communicative Effectiveness Index (Lomas et al., 1989), a previously validated measure of functional communication, was used as a comparison measure. Nineteen participants received follow-up assessment ≥ 3 weeks later.

RESULTS

Validity was supported by Pearson correlations between spoken language recordings and the VAL, r(38) = .70, p < .001. Likewise, correlation with the Communicative Effectiveness Index was strong, r(38) = .73, p < .001. Test-retest reliability for both VAL and audio recording was high, with intraclass correlations ≥ .96 and .90, respectively.

CONCLUSIONS

These results present preliminary evidence for the reliability and validity of the VAL and spoken language recording for assessment of the amount of real-world spoken language in aphasia. As a simple patient-reported outcome, the VAL may assist diverse therapies for aphasia.

Knowing What We're Doing: Why Specification of Treatment Methods Is Critical for Evidence-Based Practice in Speech-Language Pathology

PURPOSE

The purpose of this clinical focus article is to describe the conceptual framework of the multidisciplinary rehabilitation treatment taxonomy (RTT) and illustrate its potential use in speech-language pathology (SLP) clinical practice and research.

METHOD

The method used was a critical discussion.

RESULTS

Current methods of defining and classifying SLP and other rehabilitation interventions maintain the "black box" of rehabilitation by referring to hours or days of therapy or using problem-oriented labels (e.g., naming treatment) to describe treatments, none of which reveal what is actually done to effect desired changes in patient functioning. The RTT framework uses treatment targets, ingredients, and mechanisms of action defined by treatment theory to specify SLP and other rehabilitation interventions with greater precision than current methods of treatment labeling and classification. It also makes a distinction between the target of treatment at which ingredients are directed and broader aims of treatment, which may be downstream effects explained instead by enablement/disablement theory.

CONCLUSION

Future application of the RTT conceptual scheme to SLP intervention may enhance clinical practice, research, and knowledge translation as well as training and program evaluation efforts.

Intervenções em afasia: uma revisão integrativa

RESUMO O objetivo desta revisão foi identificar, avaliar e discutir artigos sobre intervenções e avanços terapêuticos em afasia, publicados periódicos científicos nos últimos cinco anos, em plataformas de livre acesso aos profissionais. Foi realizada uma revisão integrativa nas bases de dados SciELO, LILACS, Periódicos Capes e PubMed, com os descritores em português e inglês: afasia, reabilitação e tratamento. Foram incluídos artigos que descrevessem tratamentos para afasia ou histórias de reabilitação, publicados em inglês ou português. Os estudos que atenderam aos critérios foram lidos e analisados segundo instrumento para revisão integrativa, e posteriormente categorizada. Dos 96 artigos levantados 26 foram incluídos na revisão. Houve predominância de estudos quantitativos. De modo geral, diversas pesquisas que testavam terapias mostraram resultados positivos, confirmando que a afasia é uma condição que responde a uma ampla variedade de tratamentos. Nos estudos cujo foco foi a ativação cerebral, foram encontradas correlações importantes entre a melhora dos pacientes e a ativação de áreas cerebrais relacionadas à linguagem. A partir dos resultados, verificou-se que os tratamentos para afasia descritos não indicam a superioridade de uma abordagem terapêutica sobre outra. A maioria dos estudos revisados não apresentava bom grau de generalidade externa, indicando a necessidade de estudos controlados com amostras mais representativas. A literatura atualizada deve fundamentar as ações dos profissionais, porém esses devem estar atentos às características e limitações dos protocolos testados.

Constraint-Induced Aphasia Therapy for Treatment of Chronic Post-Stroke Aphasia: A Randomized, Blinded, Controlled Pilot Trial

Background

Few studies have documented the possibility of treatment-induced improvements in language functions 12 months or longer after stroke. The purpose of the current study was to provide a preliminary estimate of efficacy of constraint-induced aphasia therapy (CIAT) when compared to no-intervention in patients with chronic (>1 year) post-stroke aphasia in order to provide the data needed to design an appropriately powered trial.

Material/Methods

This was a randomized, controlled, single-blinded, pilot trial. We identified 32 patients with chronic post-stroke aphasia. Of these, 27 were offered participation, and 24 were randomized (CONSORT diagram): 14 to CIAT and to 10 to no-intervention. CIAT groups received up to 4 hours/day of intervention for 10 consecutive business days (40 hours of therapy). Outcomes were assessed within 1 week of intervention and at 1 and 12 weeks after intervention and included several linguistic measures and a measure of overall subjective communication abilities (mini-Communicative Abilities Log (mini-CAL)). To maintain blinding, clinicians treating patients (CIAT group) did not communicate with other team members and the testing team members were blinded to treatment group assignment.

Results

Overall, the results of this pilot trial support the results of previous observational studies that CIAT may lead to improvements in linguistic abilities. At 12 weeks, the treatment group reported better subjective communication abilities (mini-CAL) than the no-intervention group (p=0.019). Other measures trended towards better performance in the CIAT group.

Conclusions

In this randomized, controlled, and blinded pilot study, intensive language therapy (CIAT) led to an improvement in subjective language abilities. The effects demonstrated allow the design of a definitive trial of CIAT in patients with a variety of post-stroke aphasia types. In addition, our experiences have identified important considerations for designing subsequent trial(s) of CIAT or other interventions for post-stroke aphasia.

Bilateral brain reorganization with memantine and constraint-induced aphasia therapy in chronic post-stroke aphasia: An ERP study

Changes in ERP (P100 and N400) and root mean square (RMS) were obtained during a silent reading task in 28 patients with chronic post-stroke aphasia in a randomized, double-blind, placebo-controlled trial of both memantine and constraint-induced aphasia therapy (CIAT). Participants received memantine/placebo alone (weeks 0-16), followed by drug treatment combined with CIAT (weeks 16-18), and then memantine/placebo alone (weeks 18-20). ERP/RMS values (week 16) decreased more in the memantine group than in the placebo group. During CIAT application (weeks 16-18), improvements in aphasia severity and ERP/RMS values were amplified by memantine and changes remained stable thereafter (weeks 18-20). Changes in ERP/RMS occurred in left and right hemispheres and correlated with gains in language performance. No changes in ERP/RMS were found in a healthy group in two separated evaluations. Our results show that aphasia recovery induced by both memantine alone and in combination with CIAT is indexed by bilateral cortical potentials.

Implications of CI therapy for visual deficit training

We address here the question of whether the techniques of Constraint Induced (CI) therapy, a family of treatments that has been employed in the rehabilitation of movement and language after brain damage might apply to the rehabilitation of such visual deficits as unilateral spatial neglect and visual field deficits. CI therapy has been used successfully for the upper and lower extremities after chronic stroke, cerebral palsy (CP), multiple sclerosis (MS), other central nervous system (CNS) degenerative conditions, resection of motor areas of the brain, focal hand dystonia, and aphasia. Treatments making use of similar methods have proven efficacious for amblyopia. The CI therapy approach consists of four major components: intensive training, training by shaping, a "transfer package" to facilitate the transfer of gains from the treatment setting to everyday activities, and strong discouragement of compensatory strategies. CI therapy is said to be effective because it overcomes learned nonuse, a learned inhibition of movement that follows injury to the CNS. In addition, CI therapy produces substantial increases in the gray matter of motor areas on both sides of the brain. We propose here that these mechanisms are examples of more general processes: learned nonuse being considered parallel to sensory nonuse following damage to sensory areas of the brain, with both having in common diminished neural connections (DNCs) in the nervous system as an underlying mechanism. CI therapy would achieve its therapeutic effect by strengthening the DNCs. Use-dependent cortical reorganization is considered to be an example of the more general neuroplastic mechanism of brain structure repurposing. If the mechanisms involved in these broader categories are involved in each of the deficits being considered, then it may be the principles underlying efficacious treatment in each case may be similar. The lessons learned during CI therapy research might then prove useful for the treatment of visual deficits.

The functional significance of cortical reorganization and the parallel development of CI therapy

For the nineteenth and the better part of the twentieth centuries two correlative beliefs were strongly held by almost all neuroscientists and practitioners in the field of neurorehabilitation. The first was that after maturity the adult CNS was hardwired and fixed, and second that in the chronic phase after CNS injury no substantial recovery of function could take place no matter what intervention was employed. However, in the last part of the twentieth century evidence began to accumulate that neither belief was correct. First, in the 1960s and 1970s, in research with primates given a surgical abolition of somatic sensation from a single forelimb, which rendered the extremity useless, it was found that behavioral techniques could convert the limb into an extremity that could be used extensively. Beginning in the late 1980s, the techniques employed with deafferented monkeys were translated into a rehabilitation treatment, termed Constraint Induced Movement therapy or CI therapy, for substantially improving the motor deficit in humans of the upper and lower extremities in the chronic phase after stroke. CI therapy has been applied successfully to other types of damage to the CNS such as traumatic brain injury, cerebral palsy, multiple sclerosis, and spinal cord injury, and it has also been used to improve function in focal hand dystonia and for aphasia after stroke. As this work was proceeding, it was being shown during the 1980s and 1990s that sustained modulation of afferent input could alter the structure of the CNS and that this topographic reorganization could have relevance to the function of the individual. The alteration in these once fundamental beliefs has given rise to important recent developments in neuroscience and neurorehabilitation and holds promise for further increasing our understanding of CNS function and extending the boundaries of what is possible in neurorehabilitation.