Changes in language-specific brain activation after therapy for aphasia using magnetoencephalography: a case study

A patient with chronic aphasia underwent functional imaging during a language comprehension task using magnetoencephalography (MEG) before and after constraint induced language therapy (CILT). In the pre- and immediate post-treatment (TX) scans MEG activity sources were observed within right hemisphere only, and were located in areas homotopic to left hemisphere language areas. There was a significant increase in activation in these areas between the two sessions. This change was not observed in an age-matched patient with chronic aphasia who underwent sequential language testing and MEG scanning across a similar time period without being administered therapy. In the 3-month post-TX scan bilateral activation was observed, including significant activation within the left temporal lobe. The changes in the spatial parameters of the maps of receptive language function after therapy were accompanied by improvement in language function. Results provide support, in the same individual, for a role for both hemispheres in recovery of language function after therapy for chronic aphasia.

Functional MRI of language in aphasia: a review of the literature and the methodological challenges

Animal analogue studies show that damaged adult brains reorganize to accommodate compromised functions. In the human arena, functional magnetic resonance imaging (fMRI) and other functional neuroimaging techniques have been used to study reorganization of language substrates in aphasia. The resulting controversy regarding whether the right or the left hemisphere supports language recovery and treatment progress must be reframed. A more appropriate question is when left-hemisphere mechanisms and when right-hemisphere mechanisms support recovery of language functions. Small lesions generally lead to good recoveries supported by left-hemisphere mechanisms. However, when too much language eloquent cortex is damaged, right-hemisphere structures may provide the better substrate for recovery of language. Some studies suggest that recovery is particularly supported by homologues of damaged left-hemisphere structures. Evidence also suggests that under some circumstances, activity in both the left and right hemispheres can interfere with recovery of function. Further research will be needed to address these issues. However, daunting methodological problems must be managed to maximize the yield of future fMRI research in aphasia, especially in the area of language production. In this review, we cover six challenges for imaging language functions in aphasia with fMRI, with an emphasis on language production: (1) selection of a baseline task, (2) structure of language production trials, (3) mitigation of motion-related artifacts, (4) the use of stimulus onset versus response onset in fMRI analyses, (5) use of trials with correct responses and errors in analyses, and (6) reliability and stability of fMRI images across sessions. However, this list of methodological challenges is not exhaustive. Once methodology is advanced, knowledge from conceptually driven fMRI studies can be used to develop theoretically driven, mechanism-based treatments that will result in more effective therapy and to identify the best patient candidates for specific treatments. While the promise of fMRI in the study of aphasia is great, there is much work to be done before this technique will be a useful clinical tool.

Using Conversation Analysis to Assess and Treat People with Aphasia

This article gives an overview of the application to aphasia of conversation analysis (CA), a qualitative methodology for the analysis of recorded, naturally occurring talk produced in everyday human interaction. CA, like pragmatics, considers language use in context, but it differs from other analytical frameworks because the clinician is not making interpretations about how an aspect of language should be coded or judging whether an utterance is successful or adequate in terms of communication. We first outline the CA methodology before discussing its application to the assessment of aphasia, principally through the use of two published assessment tools. We then move on to illustrate applications of CA in the field of aphasia therapy by discussing two single case study interventions. Key conversation behaviors are illustrated with transcripts from interactions recorded by the person with aphasia and the person's habitual conversation partner in the home environment. Finally, we explore the implications of using CA as a tool for assessment and treatment in aphasia.

[Treatment of patients with aphasia--practical considerations]

Aphasia often leads to severe restrictions in communicative behaviour and social participation. Therapeutic strategies aiming at improving communicative competence usually have to be carried out over a long period and may be very costly. If prescribed, such therapies will be financed by the health insurance systems. Prescriptions, however, must respect the individual needs of a patient as well as certain restrictions outlined in insurance guidelines. This can lead to problems if the patient's or relatives' wish for therapy is completely or partially ignored. Here we discuss the rational for prescribing therapy for aphasia patients based on current guidelines and discuss how the patients and relatives can be best advised.

Stimulating language: insights from TMS

Fifteen years ago, Pascual-Leone and colleagues used transcranial magnetic stimulation (TMS) to investigate speech production in pre-surgical epilepsy patients and in doing so, introduced a novel tool into language research. TMS can be used to non-invasively stimulate a specific cortical region and transiently disrupt information processing. These 'virtual lesion' studies offer not only the ability to explore causal relations between brain regions and language functions absent in functional neuroimaging, but also spatial and temporal precision not typically available in patient studies. For instance, TMS has been used to demonstrate functionally distinct sub-regions of the left inferior frontal gyrus; to clarify the relationship between pre-morbid language organization and susceptibility to unilateral lesions and to investigate the contribution of both left and right hemisphere language areas in recovery from aphasia. When TMS is used as a measure of functional connectivity, it demonstrates a close link between action words and motor programmes; it suggests a potential evolutionary link between hand gestures and language and it suggests a role in speech perception for the motor system underlying speech production. In combination with functional neuroimaging, it can elucidate the circuits responsible for this involvement. Finally, TMS may even be useful for enhancing recovery in aphasic patients. In other words, TMS has already become an important tool for studying language at both the cognitive and neural levels, and it is clear that further developments in TMS methodology are likely to result in even greater opportunities for language research.

Complexity in the treatment of naming deficits

PURPOSE

This article discusses a novel approach for treatment of lexical retrieval deficits in aphasia in which treatment begins with complex, rather than simple, lexical stimuli. This treatment considers the semantic complexity of items within semantic categories, with a focus on their featural detail. Method and Results Previous work on training items within animate categories (S. Kiran & C. K. Thompson, 2003b) and preliminary work aimed at items within inanimate categories are discussed in this article. Both these studies indicate that training atypical category items that entail features inherent in the category prototype as well as distinctive features that are not characteristic of the category prototype results in generalization to untrained typical examples which entail only features consistent with the category prototype. Conversely, training typical examples does not result in generalization to untrained atypical examples. In this article, it is argued that atypical items are more complex than typical items within a category, and a theoretical framework for this dimension of semantic complexity is discussed. Then, evidence from treatment studies that support this complexity hierarchy is presented. Potential patient- and stimulus-specific factors that may influence the success of this treatment approach are also discussed.

CONCLUSIONS

The applications of semantic complexity to treatment of additional semantic categories and functional applications of this approach are proposed.

Comments on "comparison of alternatives to multidimensional scoring in the assessment of language comprehension in aphasia" by odekar and hallowell (2005)

PURPOSE

These comments are written in response to an article by A. Odekar and B. Hallowell (2005) which argues that the use of plus-minus scoring may be faster and more efficient than "traditional multidimensional scoring" in current clinical contexts.

METHOD

As a long-time clinician and as the developer of binary choice multidimensional scoring as used in the Porch Index of Communicative Ability (PICA), I felt it necessary to correct some inaccuracies, to provide some clarifications and cautions, and to give the readers an alternative point of view regarding scoring issues.

CONCLUSIONS

Four major issues are addressed. First, there is a growing trend to develop more, not fewer, multidimensional scoring systems because the older plus-minus method loses too much information about the patient. Second, although the Odekar and Hallowell article has an extensive discussion on the PICA, implying that this test battery is to be the focus of the study, the actual experiment employed the Revised Token Test and had little to do with the PICA. Third, the stated aim of the study, to demonstrate that plus-minus scoring is faster and less time consuming than multidimensional scoring, was not included in the experimental design. Finally, changes that replace established and effective clinical methods must not affect patient care negatively.

Complexity in treatment of syntactic deficits

PURPOSE

This article addresses complexity in the context of treatment for sentence structural impairments in agrammatic aphasia, with emphasis on noncanonical sentences involving linguistic movement and their related counterparts. Extensions of the complexity effect to recovery of canonical sentences also are discussed, stressing the linguistic properties of verbs as well as grammatical morphology in building complexity hierarchies.

METHOD

A number of variables to consider in developing complexity hierarchies in the syntactic domain are addressed, and a series of studies using single-subject controlled experimental analysis are discussed.

RESULTS

Findings across studies show that training complex sentences results in improvement of simpler structures when, and only when, the underlying linguistic properties are shared by both. The opposite approach, training simple structures first and building to more complex ones, does not provide the full benefit of treatment, in that little or no generalization occurs across structures.

CONCLUSION

Using complex language material as a starting point for treatment of sentence structural deficits in aphasia results in cascading generalization to simpler, linguistically related material and expands spontaneous language production in many language-disordered adults with aphasia. Clinicians are, therefore, urged to adopt this approach in clinical practice, even though it is counterintuitive and departs significantly from conventional treatment methods.

Recovery from aphasia as a function of language therapy in an early bilingual patient demonstrated by fMRI

Knowledge about the recovery of language functions in bilingual aphasic patients who suffer from left-hemispheric stroke is scarce. Here, we present the case of an early bilingual patient (German/French) with chronic aphasia. Functional magnetic resonance imaging (fMRI) was used to investigate neural correlates of language performance during an overt picture naming task in German and French (a) 32 months after stroke to assess differential recovery of both languages as a function of the preceding language therapy that was provided exclusively in German and (b) after additional short-term intensive (German) language training. At the first investigation behavioral performance confirmed selective recovery of German naming ability which was associated with increased functional brain activation compared to the French naming condition. Changes in behavioral performance and brain activation pattern as disclosed by fMRI after an additional experimental treatment were confined to the trained (German) language and indicate bilateral neuroplastic reorganization. No generalization to the untrained (French) language was observed. The present case results demonstrate use and/or training-dependent differential recovery of expressive language functions and an enhanced pattern of brain activation as a function of the rehabilitation efforts that were focussed exclusively on the patient's German language abilities.

Evaluating single-subject treatment research: lessons learned from the aphasia literature

The mandate for evidence-based practice has prompted careful consideration of the weight of the scientific evidence regarding the therapeutic value of various clinical treatments. In the field of aphasia, a large number of single-subject research studies have been conducted, providing clinical outcome data that are potentially useful for clinicians and researchers; however, it has been difficult to discern the relative potency of these treatments in a standardized manner. In this paper we describe an approach to quantify treatment outcomes for single-subject research studies using effect sizes. These values provide a means to compare treatment outcomes within and between individuals, as well as to compare the relative strength of various treatments. Effect sizes also can be aggregated in order to conduct meta-analyses of specific treatment approaches. Consideration is given to optimizing research designs and providing adequate data so that the value of treatment research is maximized.

Functional imaging before and after constraint-induced language therapy for aphasia using magnetoencephalography

Five patients with chronic aphasia underwent functional imaging using magnetoencephalography (MEG) before and after constraint-induced language therapy (CILT). Patients who responded well to CILT exhibited a greater degree of late MEG activation in posterior language areas of the left hemisphere and homotopic areas of the right hemisphere prior to therapy than those who did not respond well. Response to CILT, however, was positively correlated with the degree of pre-therapy MEG activity within posterior areas of the right hemisphere only on an individual basis.

[Present situation and thinking of studies on apoplectic aphasia]

There were different emphasis between Chinese medicine and Western medicine in the study of apoplectic aphasia, the study of Chinese medicine lay particular emphasis on treatment with more interfering methods but lacking unifying evaluation criteria; while studies of Western medicine lay particular emphasis on studies of mechanisms, classification and language rehabilitation of aphasia, etc.. Selection and application of scientific study methods are key to attain expectation results of studies, and deeply make studies of apoplectic aphasia, so as to explore and establish the model of integrated Chinese and western medicine study of aphasia, promote rehabilitation of language function and increase life quality of the patient of apoplexy.

Making non-fluent aphasics speak: sing along!

A classic observation in neurology is that aphasics can sing words they cannot pronounce otherwise. To further assess this claim, we investigated the production of sung and spoken utterances in eight brain-damaged patients suffering from a variety of speech disorders as a consequence of a left-hemisphere lesion. In Experiment 1, the patients were tested in the repetition and recall of words and notes of familiar material. Lyrics of familiar songs, as well as words of proverbs and prayers, were not better pronounced in singing than in speaking. Notes were better produced than words. In Experiment 2, the aphasic patients repeated and recalled lyrics from novel songs. Again, they did not produce more words in singing than in speaking. In Experiment 3, when allowed to sing or speak along with an auditory model while learning novel songs, aphasics repeated and recalled more words when singing than when speaking. Reduced speed or shadowing cannot account for this advantage of singing along over speaking in unison. The results suggest that singing in synchrony with an auditory model--choral singing--is more effective than choral speech, at least in French, in improving word intelligibility because choral singing may entrain more than one auditory-vocal interface. Thus, choral singing appears to be an effective means of speech therapy.

Safety and cost-effectiveness of intra-office flexible videolaryngoscopy with transoral vocal fold injection in dysphagic patients

SETTING

A tertiary care referral-based otolaryngology practice.

OBJECTIVES

To evaluate the safety of office-based transoral oral vocal fold injection in an ambulatory dysphagic population and to evaluate cost-effectiveness in comparison with traditional injection laryngoplasty done under general anesthesia in the operating room. Dysphagia is a nonspecific and common symptom of many head and neck and systemic disease processes. In patients with glottal incompetence, the presenting complaint of dysphagia generally portends to more global oropharyngeal dysfunction than dysphonia alone. Although many authors have reported on and advocated the use of office injection technique in the management of dysphonia caused by glottal insufficiency, there is a paucity of literature regarding the use of this technique in a more medically compromised dysphagic patient population (Ann Otol Rhinol Laryngol 1997;106:778-83). We describe our experience with vocal fold injection in the office setting using a transoral technique under flexible videolaryngoscopy for the treatment of glottal insufficiency in dysphagic patients. The safety and cost-effectiveness of this approach are highlighted.

The negotiation of intelligibility in an aphasic dyad

Employing conversation analysis as a research technique, this study investigates the ways that unintelligibility is accounted for and overcome within a therapeutic encounter between an individual with aphasia and dysarthria and his clinician. The results emphasize the collaborative nature of intelligibility negotiation and demonstrate how both the individual with the impairment and his clinician employ various interactional strategies and knowledge resources to turn unintelligibility into intelligibility so that the therapeutic encounter may continue.

Stroke recovery can be enhanced by using repetitive transcranial magnetic stimulation (rTMS)

Post-stroke recovery is based on plastic changes in the central nervous system that can compensate the loss of activity in affected brain regions. In particular, monohemispheric stroke is thought to result in disinhibition of the contralesional unaffected hemisphere. Neurorehabilitation programs improve function partly by enhancing cortical reorganization. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive way of producing potent changes in cortical excitability. Therefore, the application of rTMS was recently proposed to promote functional recovery in stroke patients, owing to the induced neuroplasticity. This review discusses the first clinical results that were obtained by rTMS in patients with post-stroke motor deficit, visuospatial neglect, or aphasia. These results are promising and depend on the site and frequency of stimulation. In summary, functional recovery might be obtained either when rTMS is applied at low-frequency (around 1 Hz) over the disinhibited, unaffected hemisphere in order to restore defective inhibition or when rTMS is applied at high-frequency (5 Hz or more) over the affected hemisphere in order to reactivate hypoactive regions. The overall procedure remains to be optimized, in particular regarding the number of rTMS sessions and the time of rTMS application after stroke. Cortical stimulation is an exciting perspective for improving functional recovery from stroke. Transient application of non-invasive transcranial stimulation during the time of the rehabilitation process will be preferable to the temporary implantation of epidural cortical electrodes, as recently proposed. Therefore, in the future, acute or recent stroke might be a major indication of rTMS in neurological practice.

Effect of semantic naming treatment on crosslinguistic generalization in bilingual aphasia

PURPOSE

The effect of semantic naming treatment on crosslinguistic generalization was investigated in 3 participants with English-Spanish bilingual aphasia.

METHOD

A single-subject experimental designed was used. Participants received semantic treatment to improve naming of English or Spanish items, while generalization was tested to untrained semantically related items in the trained language and translations of the trained and untrained items in the untrained language.

RESULTS

Results demonstrated a within- and across-languages effect on generalization related to premorbid language proficiencies. Participant 1 (P1; equal premorbid proficiency across languages) showed within-language generalization in the trained language (Spanish) as well as crosslinguistic generalization to the untrained language (English). Participant 2 (P2) and Participant (P3) were more proficient premorbidly in English. With treatment in English, P2 showed within-language generalization to semantically related items, but no crosslinguistic generalization. With treatment in Spanish, both P2 and P3 exhibited no within-language generalization, but crosslinguistic generalization to English (dominant language) occurred. Error analyses indicated an evolution of errors as a consequence of treatment.

CONCLUSIONS

These results are preliminary because all participants were not treated in both languages. However, the results suggest that training the less dominant language may be more beneficial in facilitating crosslinguistic generalization than training the more proficient language in an unbalanced bilingual individual.

Single subject controlled experiments in aphasia: the science and the state of the science

This paper discusses the use of single subject controlled experimental designs for investigating the effects of treatment for aphasia. A brief historical perspective is presented, followed by discussions of the advantages and disadvantages of single subject and group approaches, the basic requirements of single subject experimental research, and crucial considerations in design selection. In the final sections, results of reviews of published single subject controlled experiments are discussed, with emphasis on internal validity issues, the number of participants enrolled in published studies, operational specification of the dependent and independent variables, and reliability of measurement.

LEARNING OUTCOMES

As a result of reading this paper, the participant will: (1) understand the mechanisms required for demonstration of internal and external validity using single subject controlled experimental designs, (2) become familiar with the basic requirements of single subject controlled experimental research, (3) understand the types of single subject controlled experimental designs that are the most appropriate for studying the effects of treatment for aphasia, and (4) become familiar with trends in the published aphasia treatment literature in which single subject controlled experimental designs have been used.

The personalized cueing method: from the laboratory to the clinic

PURPOSE

The personalized cueing method is a novel procedure for treating naming deficits of persons with aphasia that is relatively unfamiliar to most speech-language pathologists. The goal of this article is to introduce the personalized cueing method to clinicians so that it might be expanded and improved upon. It is also hoped that this article will promote further research in the treatment of naming deficits of clients with aphasia.

METHOD

This clinical focus article (a) describes the origins of the personalized cueing method, the steps involved in creating personalized cues, and training and assessment procedures used with the personalized cueing method; (b) summarizes the published research supporting the use of the personalized cueing method; and (c) highlights some of the clinical advantages of this novel naming treatment for clients and clinicians.

RESULTS

Research with the personalized cueing method indicates that durability (long-term naming accuracy) for items trained with the personalized cueing method exceeds that for items trained with phonological cueing and other methods. It further shows that as the stimuli used to train naming in the personalized cueing experiments have become more realistic, durability of personalized cueing has increased.

CONCLUSION

Personalized cueing is a parsimonious approach for treatment of naming deficits of persons with aphasia that has shown positive treatment effects in 8-12 training sessions.

[Aphasia in stroke patients: frequency and significance]

Eine Aphasie liegt bei 21–38% aller ischämischer Hirnschlagpatienten vor. Das Risiko, eine Aphasie als Hirnschlagsymtom zu erleiden, steigt mit dem Alter an, während das Geschlecht keinen Risikofaktor darstellt. Aphasiker unter den Hirnschlagpatienten haben eine doppelt so hohe Mortalität wie Nichtaphasiker. Auch sind die Chancen, ein selbständiges, unabhängiges Leben wiederzuerlangen kompromittiert, wenn eine Aphasie vorliegt. Dennoch erreichen bis 40% der Aphasiker eine weitgehende Erholung ihrer Sprachfunktion. Die Frage, ob Logopädie bei aphasischen Hirnschlagpatienten von Nutzen ist, kann basierend auf der Studienlage nicht abschliessend beantwortet werden. Dennoch scheint eine hochfrequente, intensive Sprachtherapie in den ersten Wochen einer niederfrequenten Logopädie über einen längeren Zeitraum überlegen zu sein. Trotz ermutigender Erfahrungen mit unterstützenden Pharmaka werden weitere methodologisch einwandfreie und ausreichend grosse Studien nötig sein, bevor klar ist, ob und wie sich die funktionelle Spracherholung pharmakologisch günstig beeinflussen lässt.

The TCM-combined treatment for aphasia due to cerebrovascular disorders

OBJECTIVE

To evaluate the therapeutic effects of scalp acupuncture (with the cluster needling, a long needle-retention and an intermittent manipulation) combined with the Schuell's stimulation and psychological care for treatment of aphasia due to cerebrovascular disorders.

METHOD

36 eligible cases of aphasia were randomly assigned into a treatment group and a control group. The scoring system for assessment of aphasia in speaking Chinese set by CMA Neurological Branch and that of BADE were adopted for grading the severity/degree of aphasia before and after the treatment.

RESULTS

The total effective rate in the treatment group was 84.21%, and that in the control group was 70.59%, with a very statistically significant difference (P < 0.01).

CONCLUSION

The combined scheme produced a better therapeutic effect.

Recovery from aphasia following brain injury: the role of reorganization

Language is predominantly a left hemisphere function, yet patients with extensive damage to known language areas often recover quite well in the days to weeks to even years following focal brain injury. This recovery period can be divided into three overlapping stages: acute, subacute, and chronic, each with different underlying neural mechanisms. Reorganization of structure and function through the expression of neural plasticity plays a crucial role in recovery of language at least during the subacute phase of weeks to months after the occurrence of an injury. In this chapter we review the evidence for reorganization of language function after injury, the role it plays in the recovery of language following brain damage, and how knowledge of the mechanisms of recovery will allow design of more effective methods of rehabilitation.

Comparing fixed- and randomized-interval spaced retrieval in anomia treatment

Spaced retrieval (SR) has recently been modified to target anomia in persons with aphasia (PWA). It relies on a strict management of the inter-stimulus interval (ISI) where the time between stimulus presentations is doubled or halved based on response accuracy. Although SR is successful in treating anomia, it remains to be studied whether the strict ISI management is necessary. The present study compared fixed-interval spaced retrieval (FISR) to randomized-interval spaced retrieval (RISR) in anomia treatment. Using alternating treatments single subject design, three PWA were trained to name 30 target items. Although both treatments were successful, the present data did not reveal one approach as superior even though fewer FISR sessions were needed and more FISR items were maintained on the post-treatment probes. This difference was only minimal suggesting that a less stringent stimulus schedule, as used in RISR, is sufficient for successful treatment outcome.

LEARNING OUTCOMES

Readers will be able to describe the spaced retrieval treatment approach using both fixed- and randomized-interval stimulus schedules, as well as applications of this technique in the treatment of anomia in aphasia.