Case report: the effects of cerebellar tDCS in bilingual post-stroke aphasia.

Transcranial Direct Current Stimulation may be a useful neuromodulation tool for enhancing the effects of speech and language therapy in people with aphasia, but research so far has focused on monolinguals. We present the effects of 9 sessions of anodal cerebellar tDCS (ctDCS) coupled with language therapy in a bilingual patient with chronic post-stroke aphasia caused by left frontal ischemia, in a double-blind, sham-controlled within-subject design. Language therapy was provided in his second language (L2). Both sham and anodal treatment improved trained picture naming in the treated language (L2), while anodal ctDCS in addition improved picture naming of untrained items in L2 and his first language, L1. Picture description improved in L2 and L1 after anodal ctDCS, but not after sham.

Executive functions in primary progressive aphasia: A meta-analysis.

Executive functions (EFs) refer to a set of cognitive processes, specifically shifting, inhibition, updating of working memory, and are involved in the cognitive control of behavior. Conflicting results have been reported regarding impairments of EFs in Primary Progressive Aphasia (PPA). We performed a multi-level meta-analysis to confirm whether deficits of EFs exist in this population, focusing on a common EFs composite, and the components shifting, inhibition and updating separately. We included 141 studies that report on 294 EFs tasks. The overall mean weighted effect size was large (d = -1,28), indicating poorer EFs in PPA as compared to age-matched cognitively healthy controls. Differences between effect sizes of the EFs components were not significant, indicating all components are affected similarly. Overall, moderator analysis revealed that PPA variant and disease duration were significant moderators of performance, while task modality and years of education were not. The non-fluent/agrammatic PPA and the logopenic PPA variants were similarly affected, but the semantic variant was affected to a lesser extent. We discuss implications for clinical and research settings, and future research.

A Systematic Review of Transcranial Direct Current Stimulation in Primary Progressive Aphasia: Methodological Considerations.

A variety of tDCS approaches has been used to investigate the potential of tDCS to improve language outcomes, or slow down the decay of language competences caused by Primary Progressive Aphasia (PPA). The employed stimulation protocols and study designs in PPA are generally speaking similar to those deployed in post-stroke aphasic populations. These two etiologies of aphasia however differ substantially in their pathophysiology, and for both conditions the optimal stimulation paradigm still needs to be established. A systematic review was done and after applying inclusion and exclusion criteria, 15 articles were analyzed focusing on differences and similarities across studies especially focusing on PPA patient characteristics (age, PPA variant, language background), tDCS stimulation protocols (intensity, frequency, combined therapy, electrode configuration) and study design as recent reviews and group outcomes for individual studies suggest tDCS is an effective tool to improve language outcomes, while methodological approach and patient characteristics are mentioned as moderators that may influence treatment effects. We found that studies of tDCS in PPA have clinical and methodological and heterogeneity regarding patient populations, stimulation protocols and study design. While positive group results are usually found irrespective of these differences, the magnitude, duration and generalization of these outcomes differ when comparing stimulation locations, and when results are stratified according to the clinical variant of PPA. We interpret the results of included studies in light of patient characteristics and methodological decisions. Further, we highlight the role neuroimaging can play in study protocols and interpreting results and make recommendations for future work.

Evaluating communication partner training in healthcare centres: Understanding the mechanisms of behaviour change.

BACKGROUND: Communication between people with aphasia and their healthcare professionals (HCPs) can be greatly improved when HCPs are trained in using supportive conversation techniques and tools. Communication partner training (CPT) is an umbrella term that covers a range of interventions that train the conversation partners of people with aphasia. Several CPT interventions for HCPs have been developed and used to support HCPs to interact successfully with people with aphasia. AIMS: The objective of this study was to identify the mechanisms of change as a result of a Dutch CPT intervention, named CommuniCare, in order to evaluate and optimise the intervention. METHODS & PROCEDURES: A total of 254 HCPs from five different healthcare centres received CommuniCare. An explorative qualitative research design was chosen. Two interviews were conducted with 24 HCPs directly after and 4 months after receiving the training that was part of CommuniCare. Two conceptual frameworks were used to deductively code the interviews. HCPs' perspectives were coded into a four-part sequence following CIMO logic: the self-reported use of supportive conversation techniques or tools pre-intervention (Context), the intervention elements (Intervention) that evoked certain mechanisms (Mechanisms), resulting in the self-reported use of supportive conversation techniques and tools post-intervention (Outcomes). The Capabilities Opportunities Motivation-Behaviour (COM-B) model was used to fill in the Mechanisms component. OUTCOMES & RESULTS: Three themes were identified to describe the mechanisms of change that led to an increase in the use of supportive conversation techniques and tools. According to HCPs, (i) information, videos, e-learning modules, role-play, feedback during training and coaching on the job increased their psychological capabilities; (ii) information and role-play increased their automatic motivations; and (iii) information, videos and role-play increased their reflective motivations. Remaining findings show HCPs' perspectives on various barriers to use supportive conversation techniques and tools. CONCLUSIONS & IMPLICATIONS: HCPs in this study identified elements in our CPT intervention that positively influenced their behaviour change. Of these, role-play and coaching on the job were particularly important. HCPs suggested this last element should be better implemented. Therefore, healthcare settings wishing to enhance HCPs' communication skills should first consider enhancing HCPs' opportunities for experiential learning. Second, healthcare settings should determine which HCPs are suitable to have a role as implementation support practitioners, to support their colleagues in the use of supportive conversation techniques and tools. WHAT THIS PAPER ADDS: What is already known on this subject? Several communication partner training (CPT) interventions for healthcare professionals (HCPs) have been developed and used to support HCPs to interact successfully with people with aphasia. To date, there is limited evidence of the mechanisms of change that explain exactly what changes in HCPs' behaviour after CPT and why these changes take place. What this paper adds to existing knowledge Evaluating our CPT intervention by identifying mechanisms of change from the perspectives of HCPs provided us with: (i) a better understanding of the elements that should be included in CPT interventions in different contexts; and (ii) an understanding of the important remaining barriers identified by HCPs to use supportive conversation techniques, even after CPT is implemented. What are the potential or actual clinical implications of this work? This study shows the different intervention elements in our CPT intervention that improve HCPs' capabilities, motivations or opportunities to use supportive conversation techniques and tools. Essential ingredients of CPT according to HCPs in this study were role-play and coaching on the job by an expert and were linked to an increase in HCPs' motivations or beliefs about self-competency. Healthcare settings wishing to enhance HCPs' communication skills should therefore consider appointing implementation support practitioners to coach and support HCPs, and facilitate these practitioners to fulfil this role.

Oral and written picture description in individuals with aphasia.

BACKGROUND: Aphasia is characterized by difficulties in connected speech/writing. AIMS: To explore the differences between the oral and written description of a picture in individuals with chronic aphasia (IWA) and healthy controls. Descriptions were controlled for productivity, efficiency, grammatical organization, substitution behaviour and discourse organization. METHODS & PROCEDURES: Fifty IWA and 50 healthy controls matched for age, gender and education provided an oral and written description of a black-and-white situational drawing from the Dutch version of the Comprehensive Aphasia Test. Between- and within-group analyses were carried out and the reliability of the test instrument was assessed. OUTCOMES & RESULTS: The language samples of the healthy controls were more elaborate, more efficient, syntactically richer, more coherent, and consisted of fewer spoken and written language errors than the samples of the IWA. Within-group comparisons showed that connected writing is more sensitive than connected speech to capture aphasic symptoms. CONCLUSIONS & IMPLICATIONS: The analysis of both modalities (speech and writing) at the discourse level allows one to assess simultaneously micro- and macro-linguistic skills and their potential interrelations in a given IWA. Connected writing appears to be more sensitive in discriminating IWA from healthy controls than connected speech. This method for analyzing language samples should, however, be used in conjunction with other assessment tools.

Cerebellar induced differential polyglot aphasia: A neurolinguistic and fMRI study.

Research has shown that linguistic functions in the bilingual brain are subserved by similar neural circuits as in monolinguals, but with extra-activity associated with cognitive and attentional control. Although a role for the right cerebellum in multilingual language processing has recently been acknowledged, a potential role of the left cerebellum remains largely unexplored. This paper reports the clinical and fMRI findings in a strongly right-handed (late) multilingual patient who developed differential polyglot aphasia, ataxic dysarthria and a selective decrease in executive function due to an ischemic stroke in the left cerebellum. fMRI revealed that lexical-semantic retrieval in the unaffected L1 was predominantly associated with activations in the left cortical areas (left prefrontal area and left postcentral gyrus), while naming in two affected non-native languages recruited a significantly larger bilateral functional network, including the cerebellum. It is hypothesized that the left cerebellar insult resulted in decreased right prefrontal hemisphere functioning due to a loss of cerebellar impulses through the cerebello-cerebral pathways.

Apraxic agraphia following thalamic damage: Three new cases.

Apraxic agraphia (AA) is a so-called peripheral writing disorder following disruption of the skilled movement plans of writing while the central processes that subserve spelling are intact. It has been observed in a variety of etiologically heterogeneous neurological disorders typically associated with lesions located in the language dominant parietal and frontal region. The condition is characterized by a hesitant, incomplete, imprecise or even illegible graphomotor output. Letter formation cannot be attributed to sensorimotor, extrapyramidal or cerebellar dysfunction affecting the writing limb. Detailed clinical, neurocognitive, neurolinguistic and (functional) neuroimaging characteristics of three unique cases are reported that developed AA following a thalamic stroke. In marked contrast to impaired handwriting, non-handwriting skills, such as oral spelling, were hardly impaired. Quantified Tc-99m ECD SPECT consistently showed a decreased perfusion in the anatomoclinically suspected prefrontal regions. The findings suggest crucial involvement of the anterior (and medial) portion of the left thalamus within the neural network subserving the graphomotor system. Functional neuroimaging findings seem to indicate that AA after focal thalamic damage represents a diaschisis phenomenon.

The development of modern approaches to aphasia: a concise overview.

The aim of this article is to review the rationale on which modern aphasia test batteries are based. Since the mid-1950s, a starting point chosen because the discipline of speech (language) pathology was created during that period, a corpus of English aphasia tests was identified through searches of electronic databases. The tests were critically evaluated in terms of their theoretical roots and influences. During the past 50 years, the fundamentals of aphasia assessment remained basically unchanged, that is, to identify and gain insight into the nature and the degree of a language disturbance. However, the way in which the assessment has taken place has shifted back and forth from a purely medical approach to a more neurolinguistic or social approach depending on the influence exerted by different scientific fields. Not a single model on which aphasia assessments rely covers the many and multifaceted problems of individuals with aphasia. At several points in time during the rehabilitation process, the clinician and the patient will encounter a crossroad, where it has to be decided which path to follow next and how to evaluate the covered path. Besides application of formal test batteries, observations in different natural settings, evaluations of functional communication and insights into psychosocial coping contribute towards a holistic approach to aphasia.

Constraint-induced aphasia therapy versus intensive semantic treatment in fluent aphasia.

OBJECTIVE: The authors compared the effectiveness of 2 intensive therapy methods: Constraint-Induced Aphasia Therapy (CIAT; Pulvermüller et al., 2001) and semantic therapy (BOX; Visch-Brink & Bajema, 2001). METHOD: Nine patients with chronic fluent aphasia participated in a therapy program to establish behavioral treatment outcomes. Participants were randomly assigned to one of two groups (CIAT or BOX). RESULTS: Intensive therapy significantly improved verbal communication. However, BOX treatment showed a more pronounced improvement on two communication-namely, a standardized assessment for verbal communication, the Amsterdam Nijmegen Everyday Language Test (Blomert, Koster, & Kean, 1995), and a subjective rating scale, the Communicative Effectiveness Index (Lomas et al., 1989). All participants significantly improved on one (or more) subtests of the Aachen Aphasia Test (Graetz, de Bleser, & Willmes, 1992), an impairment-focused assessment. There was a treatment-specific effect. BOX treatment had a significant effect on language comprehension and semantics, whereas CIAT treatment affected language production and phonology. CONCLUSION: The findings indicate that in patients with fluent aphasia, (a) intensive treatment has a significant effect on language and verbal communication, (b) intensive therapy results in selective treatment effects, and (c) an intensive semantic treatment shows a more striking mean improvement on verbal communication in comparison with communication-based CIAT treatment.

Apraxic agraphia following bithalamic damage.

OBJECTIVES: Apraxic agraphia (AA) is a peripheral writing disorder generally considered to result from a causative lesion in the parietal and/or prefrontal lobe of the language dominant hemisphere (De Smet, Engelborghs, Paquier, De Deyn, & Mariën, 2011). De Smet et al. (2011), however, confirmed that AA might be associated with lesions outside the typical language areas such as the cerebellum or the thalamus. We report a 32-year-old ambidextrous patient with a left frontal lobectomy who following bilateral thalamic damage developed AA. METHOD: Detailed neurolinguistic and neurocognitive test results were obtained after resection of an extensive left frontal lobe tumour by means of a set of standardised tests. Repeated investigations were performed after a bithalamic stroke. Functional imaging was performed by means of quantified SPECT. RESULTS: Normal neurolinguistic test results were obtained after tumour resection. Neurocognitive test results, however, showed a dysexecutive syndrome and frontal behavioural deficits, including response inhibition. AA occurred after a bithalamic stroke while non-handwriting written language skills, such as typing, were normal. Quantified SPECT showed a significant bifrontal hypoperfusion. CONCLUSION: Neurolinguistic follow-up findings and SPECT evidence in this unique patient with bithalamic damage for the first time indicate that AA in the alphabetic script may result from diaschisis affecting the frontal writing centre. The findings suggest that the thalamus is critically implicated in the neural network subserving graphomotor processing.