Improved language in a chronic nonfluent aphasia patient after treatment with CPAP and TMS

Semantic and Phonological Abilities Inform Efficacy of Transcranial Magnetic Stimulation on Sustained Aphasia Treatment Outcomes

A growing body of evidence has shown that repetitive transcranial magnetic stimulation (rTMS) can enhance word-retrieval abilities in chronic aphasia. However, there remains significant variability in the efficacy of combined rTMS and language treatments. This study investigated how semantic and phonological characteristics of baseline word-retrieval impairments may influence the efficacy of rTMS on long-term naming improvements following language treatment in individuals with chronic aphasia. Thirty participants with post-stroke aphasia underwent 10 sessions of 1 Hz rTMS to right pars triangularis followed by a modified constraint-induced language treatment (mCILT). Nineteen participants were randomly assigned to active rTMS and 11 participants were assigned to sham rTMS. All participants completed the Philadelphia Naming Test (PNT) at baseline and at 3 and 6 months post-treatment. We coded PNT errors and fit data to the semantic-phonological (or SP) computational model (Foygel & Dell, 2000) to derive semantic and phonological parameter weights. We ran linear regressions for the proportional improvement in naming, with fixed effects for interactions between rTMS, time, and baseline parameter weights. While there was no immediate effect of rTMS post-treatment, rTMS combined with mCILT improved long-term naming more than language therapy alone. Furthermore, greater baseline semantic and phonological characteristics of word-retrieval abilities were each associated with increased rTMS-induced gains in proportional naming improvements. These patterns were maintained at both 3 and 6 months post-treatment. This study is among the first in a larger sample to demonstrate that individual differences in lexical retrieval contribute to variability in sustained rTMS and aphasia treatment outcomes.

A Rose by Any Other Name: Mapping Taxonomic and Thematic Naming Errors Poststroke

Understanding the neurobiology of semantic knowledge is a major goal of cognitive neuroscience. Taxonomic and thematic semantic knowledge are represented differently within the brain's conceptual networks, but the specific neural mechanisms remain unclear. Some neurobiological models propose that the anterior temporal lobe is an important hub for taxonomic knowledge, whereas the TPJ is especially involved in the representation of thematic knowledge. However, recent studies have provided divergent evidence. In this context, we investigated the neural correlates of taxonomic and thematic confrontation naming errors in 79 people with aphasia. We used three complementary lesion-symptom mapping (LSM) methods to investigate how structure and function in both spared and impaired brain regions relate to taxonomic and thematic naming errors. Voxel-based LSM mapped brain damage, activation-based LSM mapped BOLD signal in surviving tissue, and network-based LSM mapped white matter subnetwork integrity to error type. Voxel- and network-based lesion symptom mapping provided converging evidence that damage/disruption of the left mid-to-anterior temporal lobe was associated with a greater proportion of thematic naming errors. Activation-based lesion symptom mapping revealed that higher BOLD signal in the left anterior temporal lobe during an in-house naming task was associated with a greater proportion of taxonomic errors on the Philadelphia Naming Test administered outside of the scanner. A lower BOLD signal in the bilateral angular gyrus, precuneus, and right inferior frontal cortex was associated with a greater proportion of taxonomic errors. These findings provide novel evidence that damage to the anterior temporal lobe is especially related to thematic naming errors.

Non-invasive brain stimulation in the treatment of post-stroke aphasia: a scoping review

PURPOSE

Aphasia is an acquired language impairment that commonly results from stroke. Non-invasive brain stimulation (NIBS) might accelerate aphasia recovery trajectories and has seen mounting popularity in recent aphasia rehabilitation research. The present review aimed to: (1) summarise all existing literature on NIBS as a post-stroke aphasia treatment; and (2) provide recommendations for future NIBS-aphasia research.

MATERIALS AND METHODS

Databases for published and grey literature were searched using scoping review methodology. 278 journal articles, conference abstracts/posters, and books, and 38 items of grey literature, were included for analysis.

RESULTS

Quantitative analysis revealed that ipsilesional anodal transcranial direct current stimulation and contralesional 1-Hz repetitive transcranial magnetic stimulation were the most widely used forms of NIBS, while qualitative analysis identified four key themes including: the roles of the hemispheres in aphasia recovery and their relationship with NIBS; heterogeneity of individuals but homogeneity of subpopulations; individualisation of stimulation parameters; and much remains under-explored in the NIBS-aphasia literature.

CONCLUSIONS

Taken together, these results highlighted systemic challenges across the field such as small sample sizes, inter-individual variability, lack of protocol optimisation/standardisation, and inadequate focus on aphasiology. Four key recommendations are outlined herein to guide future research and refine NIBS methods for post-stroke aphasia treatment.

Repetitive Transcranial Magnetic Stimulation for Action Naming in Aphasia Rehabilitation: A Systematic Review and Meta-Analysis

Anomia, characterized by difficulty in word retrieval, particularly action verbs, poses a significant challenge in post-stroke aphasia. Repetitive transcranial magnetic stimulation (rTMS) has gained attention for language processing investigations and interventions. This systematic review explores the potential of rTMS as a modality to address action-verb deficits in post-stroke aphasia. We searched MEDLINE via PubMed, CINAHL via Ebsco and Web of Science in February 2024 for English articles (1996-2024). Eligible studies involved post-stroke aphasia action naming rehabilitation with rTMS. In some of these studies, rTMS was combined with speech-language therapy. In total, 10 studies were included in this systematic review. These articles highlight the potential of rTMS in improving verb retrieval deficits. While significant improvements may not be evident, notable progress both before and after intervention is observed in this review. However, it also underscores the need for further research to enhance language recovery for individuals with post-stroke aphasia.

Repetitive transcranial magnetic stimulation for post-stroke non-fluent aphasia: a systematic review and meta-analysis of randomized controlled trials

Objective

To systematically evaluate the efficacy and safety of repetitive transcranial magnetic stimulation (rTMS) on language function in patients with non-fluent aphasia post-stroke.

Methods

We selected randomized clinical trials (RCT) that involved stroke patients with non-fluent aphasia, whose intervention was rTMS vs. no therapy or other therapy. Two researchers autonomously reviewed the literature based on the specified criteria for inclusion and exclusion and completed the process of data extraction, data verification, and quality evaluation. Meta-analysis was performed using RevMan 5.4 and Stata MP 17, while the assessment of risk of bias was carried out utilizing the Risk of Bias version 2 tool (RoB2).

Results

The meta-analysis involved 47 RCTs, encompassing 2,190 patients overall. The indexes indicated that rTMS has the potential to decrease the severity of non-fluent aphasia in stroke patients, including improvement of the capability of repetition, naming, and spontaneous language. The determination of BDNF in the serum of patients was also increased. In addition, rTMS reduced the likelihood of depression in stroke patients.

Conclusion

To summarize the relevant studies, rTMS has significant effects on improving the language abilities of stroke patients suffering from non-fluent aphasia, including the abilities of repetition, naming, and spontaneous language.

Getting language right: Relating individual differences in right hemisphere contributions to language learning and relearning

Language, or the diverse set of dynamic processes through which symbolic, perceptual codes are linked to meaning representations in memory, has long been assumed to be lateralized to the left hemisphere (LH). However, after over 150 years of investigation, we still lack a unifying account of when, and for whom, a particular linguistic process relies upon LH or right hemisphere (RH) computations, or both. With a focus on individual differences, this article integrates existing theories of hemispheric contributions to language and cognition into a novel proposed framework for understanding how, when, and for whom the RH contributes to linguistic processes. We use evidence from first and second language learning and language relearning following focal brain damage to highlight the critical contributions of the RH.

Functional Remodeling Associated With Language Recovery After Repetitive Transcranial Magnetic Stimulation in Chronic Aphasic Stroke

Background

Repetitive transcranial magnetic stimulation (rTMS) has shown promising efficacy in improving the language functions in poststroke aphasia. However, randomized controlled trials were lacking to investigate the rTMS-related neuroimaging changes underlying the therapeutic effects on language improvement in chronic aphasia.

Objective

In this study, we aimed to evaluate the effects of low-frequency rTMS (LF-rTMS) on chronic poststroke aphasia. We hypothesized that the deactivation of the right pars triangularis could restore the balance of interhemispheric inhibition and, hence, facilitated the functional remodeling of language networks in both the hemispheres. Furthermore, the rTMS-induced functional reorganization should underpin the language recovery after rTMS.

Methods

A total of 33 patients (22 males; age: 58.70 ± 13.77 years) with chronic stroke in the left hemisphere and nonfluent aphasia were recruited in this randomized double-blinded study. The ratio of randomization between the rTMS and sham groups is 17:16. All the patients received real 1-Hz rTMS or sham stimulation (placebo coil delivered < 5% of magnetic output with similar audible click-on discharge) at the right posterior pars triangularis for 10 consecutive weekdays (stroke onset to the first stimulation: 10.97 ± 10.35 months). Functional connectivity of language networks measured by resting-state fMRI was calculated and correlated to the scores of the Concise Chinese Aphasia Test by using the stepwise regression analysis.

Results

After LF-rTMS intervention, significant improvement in language functions in terms of comprehension and expression abilities was observed compared with the sham group. The rTMS group showed a significant decrease of coupling strength between right pars triangularis and pars opercularis with a strengthened connection between right pars orbitalis and angular gyrus. Furthermore, the LF-rTMS significantly enhanced the coupling strength associated with left Wernicke area. Results of regression analysis showed that the identified functional remodeling involving both the hemispheres could support and predict the language recovery after LF-rTMS treatment.

Conclusion

We reported the therapeutic effects of LF-rTMS and corresponding functional remodeling in chronic poststroke aphasia. Our results provided neuroimage evidence reflecting the rebalance of interhemispheric inhibition induced by LF-rTMS, which could facilitate future research in the refinement of rTMS protocol to optimize the neuromodulation efficacy and benefit the clinical management of patients with stroke.

Noninvasive brain stimulation to augment language therapy for poststroke aphasia

Behavioral language treatment approaches represent the standard of care for persons with aphasia (PWA), but the benefits of these treatments are variable. Moreover, due to the logistic and financial limitations on the amount of behavioral therapy available to patients, it is often infeasible for PWA to receive behavioral interventions with the level of frequency, intensity, or duration that would provide significant and lasting benefit, underscoring the need for novel, effective treatment approaches. Noninvasive brain stimulation (NIBS) techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have emerged as promising neurally-based tools to enhance language abilities for PWA following stroke. This chapter first provides an overview of the methods and physiologic basis motivating the use of NIBS to enhance aphasia recovery followed by a selective review of the growing evidence of its potential as a novel therapeutic tool. Subsequent sections discuss some of the principles that may prove most useful in guiding and optimizing the effects of NIBS on aphasia recovery, focusing on how the functional state of the brain at the time of stimulation interacts with the behavioral aftereffects of neuromodulation. We conclude with a discussion of current challenges and future directions for NIBS in aphasia treatment.

Low-Frequency vs. Theta Burst Transcranial Magnetic Stimulation for the Treatment of Chronic Non-fluent Aphasia in Stroke: A Proof-of-Concept Study

BACKGROUND

Although low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) has shown promise in the treatment of poststroke aphasia, the efficacy of high-frequency rTMS (HF-rTMS) has yet to be determined.

PURPOSE

We investigated the efficacy of intermittent theta burst stimulation (iTBS) in ameliorating chronic non-fluent aphasia and compared it with that of LF-rTMS.

METHODS

We randomly assigned patients with poststroke non-fluent aphasia to an ipsilesional iTBS (n = 29), contralesional 1-Hz rTMS (n = 27), or sham (n = 29) group. Each group received the rTMS protocol executed in 10 daily sessions over 2 weeks. We evaluated language function before and after the intervention by using the Concise Chinese Aphasia Test (CCAT).

RESULTS

Compared with the sham group, the iTBS group exhibited significant improvements in conversation, description, and expression scores (P = 0.0004-0.031), which characterize verbal production, as well as in auditory comprehension, reading comprehension, and matching scores (P < 0.01), which characterize language perception. The 1-Hz group exhibited superior improvements in expression, reading comprehension, and imitation writing scores compared with the sham group (P < 0.05). The iTBS group had significantly superior results in CCAT total score, matching and auditory comprehension (P < 0.05) relative to the 1-Hz group.

CONCLUSION

Our study findings contribute to a growing body of evidence that ipsilesional iTBS enhances the language recovery of patients with non-fluent aphasia after a chronic stroke. Auditory comprehension was more preferentially enhanced by iTBS compared with the 1-Hz protocol. Our findings highlight the importance of ipsilesional modulation through excitatory rTMS for the recovery of non-fluent aphasia in patients with chronic stroke.

CLINICAL TRIAL REGISTRATION

[www.ClinicalTrials.gov], identifier [NCT03059225].

Effectiveness and safety of repetitive transcranial magnetic stimulation (rTMS) on aphasia in cerebrovascular accident patients: Protocol of a systematic review and meta-analysis

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS), a non-invasive brain stimulation approach, might be a promising technique in the management of aphasia after cerebrovascular accidents (CVA). This protocol of systematic review (SR) aims to investigate the effectiveness and safety of rTMS in patients with aphasia after CVA.

METHODS

The following databases will be searched: PubMed, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), China National Knowledge infrastructure (CNKI), Technology Periodical Database (VIP), WanFang Data, and China Biology Medicine (CBM) from inception to August 2019. Randomized controlled trials (RCTs) investigating the effectiveness and safety of rTMS for aphasia patients after CVA will be included. Primary outcome will include Boston Diagnostic Aphasia Examination (BDAE). Secondary outcomes will include Aphasia Battery of Chinese (ABC), Aachen Aphasia Test (AAT), Aphasia Quotient (AQ), the Western Aphasia Battery (WAB), Standard Language Test of Aphasia (SLTA), Aphasia Severity Rating Scale (ASRS), Concise China Aphasia Test Scale (CCAT), Amsterdam-Nijmegen Everyday Language Test (ANELT), or other related outcomes. Adverse events such as headache, tinnitus, anxiety, fatigue, or epileptic seizure will be considered as safety measurement. Studies screening, data extraction, and methodological quality assessment will be performed independently by two reviewers. Meta-analysis will be conducted with Review Manager 5.3 software and R software 3.6.1.

RESULTS

This study will provide a high-quality synthesis of RCTs on the effectiveness and safety of rTMS as an adjuvant therapy in the treatment of aphasia.

CONCLUSION

The conclusion of this study will help clinicians and patients with aphasia after CVA to make decision.

ETHICS AND DISSEMINATION

No privacy health information will be collected, thus formal ethics approval is not required. The findings of this SR will be submitted to a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42019144587.

Physical energies to the rescue of damaged tissues

Rhythmic oscillatory patterns sustain cellular dynamics, driving the concerted action of regulatory molecules, microtubules, and molecular motors. We describe cellular microtubules as oscillators capable of synchronization and swarming, generating mechanical and electric patterns that impact biomolecular recognition. We consider the biological relevance of seeing the inside of cells populated by a network of molecules that behave as bioelectronic circuits and chromophores. We discuss the novel perspectives disclosed by mechanobiology, bioelectromagnetism, and photobiomodulation, both in term of fundamental basic science and in light of the biomedical implication of using physical energies to govern (stem) cell fate. We focus on the feasibility of exploiting atomic force microscopy and hyperspectral imaging to detect signatures of nanomotions and electromagnetic radiation (light), respectively, generated by the stem cells across the specification of their multilineage repertoire. The chance is reported of using these signatures and the diffusive features of physical waves to direct specifically the differentiation program of stem cells in situ, where they already are resident in all the tissues of the human body. We discuss how this strategy may pave the way to a regenerative and precision medicine without the needs for (stem) cell or tissue transplantation. We describe a novel paradigm based upon boosting our inherent ability for self-healing.

Therapy-Induced Plasticity in Chronic Aphasia Is Associated with Behavioral Improvement and Time Since Stroke

Cortical reorganization after stroke is thought to underlie functional improvement. Patterns of reorganization may differ depending on the amount of time since the stroke or the degree of improvement. We investigated these issues in a study of brain connectivity changes with aphasia therapy. Twelve individuals with chronic aphasia participated in a 6-week trial of imitation-based speech therapy. We assessed improvement on a repetition test and analyzed effective connectivity during functional magnetic resonance imaging of a speech observation task before and after therapy. Using structural equation modeling, patient networks were compared with a model derived from healthy controls performing the same task. Independent of the amount of time since the stroke, patients demonstrating behavioral improvement had networks that reorganized to be more similar to controls in two functional pathways in the left hemisphere. Independent of behavioral improvement, patients with remote infarcts (2-7 years poststroke; n = 5) also reorganized to more closely resemble controls in one of these pathways. Patients with far removed injury (>10 years poststroke; n = 3) did not show behavioral improvement and, despite similarities to the normative model and overall network heterogeneity, reorganized to be less similar to controls following therapy in a distinct right-lateralized pathway. Behavioral improvement following aphasia therapy was associated with connectivity more closely approximating that of healthy controls. Individuals who had a stroke more than a decade before testing also showed plasticity, with a few pathways becoming less like controls, possibly representing compensation. Better understanding of these mechanisms may help direct targeted brain stimulation.

Pre-articulatory electrical activity associated with correct naming in individuals with aphasia

Picture naming is a language task that involves multiple neural networks and is used to probe aphasia-induced language deficits. The pattern of neural activation seen in healthy individuals during picture naming is disrupted in individuals with aphasia, but the time-course of the disruption remains unclear. Specifically, it remains unclear which anatomical and temporal aspects of neural processing are necessary for correct naming. Here, we tested two individuals with stroke induced aphasia, and compared the differences in the event-related potentials (ERPs) and current sources when they made correct vs. erroneous responses during picture naming. The pre-articulatory ERP activity was significantly different between the two responses. Current source analysis revealed that the ability to recruit left temporal and frontal areas within a 300-550 ms time window after stimulus onset contributed to correct responses. These results suggest that targeted neuromodulation in these areas could lead to better treatment outcomes in patients with aphasia.

Functional Reorganization of Right Prefrontal Cortex Underlies Sustained Naming Improvements in Chronic Aphasia via Repetitive Transcranial Magnetic Stimulation

BACKGROUND AND OBJECTIVE

While noninvasive brain stimulation techniques show promise for language recovery after stroke, the underlying mechanisms remain unclear. We applied inhibitory repetitive transcranial magnetic stimulation (rTMS) to regions of interest in the right inferior frontal gyrus of patients with chronic poststroke aphasia and examined changes in picture naming performance and cortical activation.

METHODS

Nine patients received 10 days of 1-Hz rTMS (Monday through Friday for 2 weeks). We assessed naming performance before and immediately after stimulation on the first and last days of rTMS therapy, and then again at 2 and 6 months post-rTMS. A subset of six of these patients underwent functional magnetic resonance imaging pre-rTMS (baseline) and at 2 and 6 months post-rTMS.

RESULTS

Naming accuracy increased from pre- to post-rTMS on both the first and last days of treatment. We also found naming improvements long after rTMS, with the greatest improvements at 6 months post-rTMS. Long-lasting effects were associated with a posterior shift in the recruitment of the right inferior frontal gyrus: from the more anterior Brodmann area 45 to the more posterior Brodmann areas 6, 44, and 46. The number of left hemispheric regions recruited for naming also increased.

CONCLUSIONS

This study found that rTMS to the right hemisphere Broca area homologue confers long-lasting improvements in picture naming performance. The mechanism involves dynamic bilateral neural network changes in language processing, which take place within the right prefrontal cortex and the left hemisphere more generally.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (Identifier NCT00608582).

Neuroimaging of stroke recovery from aphasia - Insights into plasticity of the human language network

The role of left and right hemisphere brain regions in language recovery after stroke-induced aphasia remains controversial. Here, we summarize how neuroimaging studies increase the current understanding of functional interactions, reorganization and plasticity in the language network. We first discuss the temporal dynamics across the time course of language recovery, with a main focus on longitudinal studies from the acute to the chronic phase after stroke. These studies show that the functional contribution of perilesional and spared left hemisphere as well as contralesional right hemisphere regions to language recovery changes over time. The second section introduces critical variables and recent advances on early prediction of subsequent outcome. In the third section, we outline how multi-method approaches that combine neuroimaging techniques with non-invasive brain stimulation elucidate mechanisms of plasticity and reorganization in the language network. These approaches provide novel insights into general mechanisms of plasticity in the language network and might ultimately support recovery processes during speech and language therapy. Finally, the neurobiological correlates of therapy-induced plasticity are discussed. We argue that future studies should integrate individualized approaches that might vary the combination of language therapy with specific non-invasive brain stimulation protocols across the time course of recovery. The way forward will include the combination of such approaches with large data sets obtained from multicentre studies.

Shining light on the head: Photobiomodulation for brain disorders

Photobiomodulation (PBM) describes the use of red or near-infrared light to stimulate, heal, regenerate, and protect tissue that has either been injured, is degenerating, or else is at risk of dying. One of the organ systems of the human body that is most necessary to life, and whose optimum functioning is most worried about by humankind in general, is the brain. The brain suffers from many different disorders that can be classified into three broad groupings: traumatic events (stroke, traumatic brain injury, and global ischemia), degenerative diseases (dementia, Alzheimer's and Parkinson's), and psychiatric disorders (depression, anxiety, post traumatic stress disorder). There is some evidence that all these seemingly diverse conditions can be beneficially affected by applying light to the head. There is even the possibility that PBM could be used for cognitive enhancement in normal healthy people. In this transcranial PBM (tPBM) application, near-infrared (NIR) light is often applied to the forehead because of the better penetration (no hair, longer wavelength). Some workers have used lasers, but recently the introduction of inexpensive light emitting diode (LED) arrays has allowed the development of light emitting helmets or "brain caps". This review will cover the mechanisms of action of photobiomodulation to the brain, and summarize some of the key pre-clinical studies and clinical trials that have been undertaken for diverse brain disorders.

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.

Cutaneous wound healing: Current concepts and advances in wound care

A non-healing wound is defined as showing no measurable signs of healing for at least 30 consecutive treatments with standard wound care.[1] It is a snapshot of a patient's total health as well as the ongoing battle between noxious factors and the restoration of optimal macro and micro circulation, oxygenation and nutrition. In practice, standard therapies for non-healing cutaneous wounds include application of appropriate dressings, periodic debridement and eliminating causative factors.[2] The vast majority of wounds would heal by such approach with variable degrees of residual morbidity, disability and even mortality. Globally, beyond the above therapies, newer tools of healing are selectively accessible to caregivers, for various logistical or financial reasons. Our review will focus on the use of hyperbaric oxygen therapy (HBOT), as used at our institution (CAMC), and some other modalities that are relatively accessible to patients. HBOT is a relatively safe and technologically simpler way to deliver care worldwide. However, the expense for including HBOT as standard of care for recognized indications per UHMS(Undersea and Hyperbaric Medical Society) may vary widely from country to country and payment system.[3] In the USA, CMS (Centers for Medicare and Medicaid Services) approved indications for HBOT vary from that of the UHMS for logistical reasons.[1] We shall also briefly look into other newer therapies per current clinical usage and general acceptance by the medical community. Admittedly, there would be other novel tools with variable success in wound healing worldwide, but it would be difficult to include all in this treatise.

Improvement of language functions in a chronic non-fluent post-stroke aphasic patient following bilateral sequential theta burst magnetic stimulation

In chronic non-fluent aphasia patients, inhibition of the intact right hemisphere (RH), by transcranial magnetic stimulation (TMS) or similar methods, can induce improvement in language functions. The supposed mechanism behind this improvement is a release of preserved left hemisphere (LH) language networks from RH transcallosal inhibition. Direct stimulation of the damaged LH can sometimes bring similar results too. Therefore, we developed a novel treatment approach that combined direct LH (Broca's area (BA)) stimulation, by intermittent theta burst stimulation (TBS), with homologue RH area's inhibition, by continuous TBS. We present the results of application of 15 daily sessions of the described treatment approach in a right-handed patient with chronic post-stroke non-fluent aphasia. The intervention appeared to improve several language functions, but most notably propositional speech, semantic fluency, short-term verbal memory, and verbal learning. Bilateral TBS modulation of activation of the language-related areas of both hemispheres seems to be a feasible and promising way to induce recovery in chronic aphasic patients. Due to potentially cumulative physiological effects of bilateral stimulation, the improvements may be even greater than following unilateral interventions.

Augmenting melodic intonation therapy with non-invasive brain stimulation to treat impaired left-hemisphere function: two case studies

The purpose of this study was to investigate whether or not the right hemisphere can be engaged using Melodic Intonation Therapy (MIT) and excitatory repetitive transcranial magnetic stimulation (rTMS) to improve language function in people with aphasia. The two participants in this study (GOE and AMC) have chronic non-fluent aphasia. A functional Magnetic Resonance Imaging (fMRI) task was used to localize the right Broca's homolog area in the inferior frontal gyrus for rTMS coil placement. The treatment protocol included an rTMS phase, which consisted of 3 treatment sessions that used an excitatory stimulation method known as intermittent theta burst stimulation, and a sham-rTMS phase, which consisted of 3 treatment sessions that used a sham coil. Each treatment session was followed by 40 min of MIT. A linguistic battery was administered after each session. Our findings show that one participant, GOE, improved in verbal fluency and the repetition of phrases when treated with MIT in combination with TMS. However, AMC showed no evidence of behavioral benefit from this brief treatment trial. Post-treatment neural activity changes were observed for both participants in the left Broca's area and right Broca's homolog. These case studies indicate that a combination of MIT and rTMS applied to the right Broca's homolog has the potential to improve speech and language outcomes for at least some people with post-stroke aphasia.

Language improvements after TMS plus modified CILT: Pilot, open-protocol study with two, chronic nonfluent aphasia cases

PURPOSE

The purpose of this study was to investigate: 1) the feasibilty of administering a modified CILT (mCILT) treatment session immediately after TMS; and 2) if this combined therapy could improve naming and elicited propositional speech in chronic, nonfluent aphasia.

METHODS

Two chronic stroke patients with nonfluent aphasia (mild-moderate and severe) each received twenty minutes of rTMS to suppress the right pars triangularis, followed immediately by three hours of mCILT (5 days/week, 2 weeks). (Each patient had received TMS alone, 2-6 years prior.) Language evaluations were performed pre- TMS+mCILT, and post- at 1-2 months, and 6 or 16 months.

RESULTS

Both patients showed significant improvements in naming pictures, and elicited propositional speech at 1-2 months post- TMS+mCILT. The improved naming was still present at 6 months post- TMS+mCILT for P2; but not at 16 months post- TMS+mCILT for P1.

CONCLUSIONS

It is feasible to administer mCILT for three hours immediately after a TMS session. It is unknown if the significant improvements in naming pictures, and elicited propositional speech were associated with the second series of TMS, or this first series of mCILT, or a combination of both. A larger, sham controlled clinical trial is warranted.

Induction of neuroplasticity and recovery in post-stroke aphasia by non-invasive brain stimulation

Stroke victims tend to prioritize speaking, writing, and walking as the three most important rehabilitation goals. Of note is that two of these goals involve communication. This underscores the significance of developing successful approaches to aphasia treatment for the several hundred thousand new aphasia patients each year and over 1 million stroke survivors with chronic aphasia in the U.S. alone. After several years of growth as a research tool, non-invasive brain stimulation (NBS) is gradually entering the arena of clinical aphasiology. In this review, we first examine the current state of knowledge of post-stroke language recovery including the contributions from the dominant and non-dominant hemispheres. Next, we briefly discuss the methods and the physiologic basis of the use of inhibitory and excitatory repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) as research tools in patients who experience post-stroke aphasia. Finally, we provide a critical review of the most influential evidence behind the potential use of these two brain stimulation methods as clinical rehabilitative tools.

Options to enhance recovery from aphasia by means of non-invasive brain stimulation and action observation therapy

Aphasia is a highly disabling language disorder usually caused by a left-lateralized brain damage. Even if traditional linguistic-based therapies have been proved to induce an adequate clinical improvement, a large percentage of patients are left with some degree of language impairments. Therefore, new approaches to common speech therapies are urgently needed in order to maximize the recovery from aphasia. The recent application of non-invasive neurostimulation techniques to language rehabilitation has already provided promising results particularly for the recovery of word-retrieval deficits in chronic stroke aphasic patients. Positive outcomes also come from action observation therapy. Indeed, some very recent studies have shown that the observation and/or execution of gestures positively influences language recovery especially for words related to human actions. This article gives an overview of the most important results achieved using these two approaches and discusses how the application of these treatments might potentiate aphasia recovery.

Excitatory Deep Transcranial Magnetic Stimulation With H-Coil Over the Right Homologous Broca’s Region Improves Naming in Chronic Post-stroke Aphasia

Background. The role of the right hemisphere in poststroke aphasia recovery is still controversial and the effects of repetitive transcranial magnetic stimulation (rTMS) over the right homologous Broca’s region have been seldom investigated. Objective. This study aimed to compare the effect of excitatory, inhibitory, and sham rTMS delivered with H-coil over the right inferior frontal gyrus in chronic aphasic patients. Methods. Five right-handed poststroke aphasic patients underwent a picture naming task before and immediately after each of 3 sessions of rTMS: excitatory (10 Hz), inhibitory (1 Hz), and sham rTMS, in random sequence and separated by at least 1 week. Results. Only the excitatory 10-Hz stimulation was associated with a significant improvement in naming performance ( P = .043) and was significantly more effective than 1-Hz rTMS ( P = .043). Conclusions. A single session of excitatory deep brain rTMS over the right inferior frontal gyrus with H-coil significantly improves naming in right-handed chronic poststroke aphasic patients. This result is in line with the hypothesis of a positive, rather than detrimental, role of the right hemisphere in chronic aphasia due to a left-hemispheric stroke.

Instrumentos para avaliação da linguagem pós-lesão cerebrovascular esquerda

O tema deste estudo é a avaliação padronizada da linguagem em pacientes com lesão cerebrovascular esquerda (LHE) que pode ser muito útil no estabelecimento do diagnóstico, prognóstico e plano terapêutico, complementando observação, entrevistas e tarefas clínicas. Este estudo teve como objetivo identificar quais instrumentos de investigação de linguagem têm sido utilizados para avaliação de quadros neurológicos súbitos envolvendo o hemisfério esquerdo (HE) e analisar quais componentes linguísticos são os mais avaliados. Foi possível identificar nove instrumentos utilizados internacionalmente que avaliam diferentes componentes linguísticos em pacientes com LHE; no contexto nacional, porém, foram encontradas apenas duas baterias para avaliação dessa população, ficando evidente a necessidade da construção e/ou de adaptação de instrumentos para a população brasileira. Os componentes linguísticos mais investigados foram nomeação e compreensão oral, respectivamente. A avaliação da linguagem torna-se essencial nos quadros envolvendo o HE, pois déficits linguísticos podem acarretar prejuízos sociais, ocupacionais e familiares.

rTMS as a treatment for neurogenic communication and swallowing disorders

Recent years have seen the introduction of non-invasive brain stimulation techniques (e.g. transcranial direct current stimulation and transcranial magnetic stimulation) utilized to target neural-based pathologies, for therapeutic gain. The direct manipulation of cortical brain activity by repetitive transcranial magnetic stimulation (rTMS) could potentially serve as an efficacious complimentary rehabilitatory treatment for speech, language and swallowing disorders of a neurological origin. The high prevalence of positive reports on communication and swallowing outcomes support these premises. Nonetheless, experimental evidence to date in some areas is considered rudimentary and is deficient in providing placebo-controlled substantiation of longitudinal neuroplastic change subsequent to stimulation. The most affirmative therapeutic responses have arisen from small placebo-controlled trials using low-frequency rTMS for patients with non-fluent aphasia and high-frequency rTMS applied to individuals with Parkinson's disease to improve motor speech performance and outcomes. Preliminary studies applying rTMS to ameliorate dysphagic symptoms post-stroke provide positive swallowing outcomes for patients. Further research into the optimization of rTMS protocols, including dosage, stimulation targets for maximal efficacy and placebo techniques, is critically needed to provide a fundamental basis for clinical interventions using this technique. rTMS represents a highly promising and clinically relevant technique, warranting the future development of clinical trials across a spectrum of communication and swallowing pathologies, to substantiate and expand on the methods outlined in published reports.

Changes in white matter integrity follow excitatory rTMS treatment of post-stroke aphasia

PURPOSE

In this study, we examine whether an excitatory repetitive transcranial magnetic stimulation (rTMS) protocol called intermittent theta burst stimulation (iTBS) applied to the affected left hemisphere leads to changes in white matter fractional anisotropy (FA).

METHODS

Diffusion tensor imaging (DTI) data were collected in 8 aphasic stroke patients before and after 10 daily iTBS treatments. Alignment of structural and DTI data and derivation of diffusion index maps were performed using Analysis of Functional NeuroImages software followed by Tract-Based Spatial Statistics using FMRIB Software Library. Paired t-tests were performed to compare pre- to post-rTMS changes in FA.

RESULTS

There were significant (p < 0.001) left-hemispheric FA increases near the inferior and superior frontal gyri and anterior corpus callosum. FA also increased in the right midbrain and bilaterally near temporal, parietal and posterior cingulate regions. FA decreased bilaterally near the fusiform gyrus and in left cerebellum.

CONCLUSIONS

Overall, left-hemispheric regions that showed increased FA corresponded to areas previously shown to have increases in fMRI language activation after iTBS. The increased white matter integrity near the stimulation sites may reflect improvements in cortical function mediated by excitatory rTMS through its ability to facilitate synaptic connections.

Grey and white matter correlates of picture naming: evidence from a voxel-based lesion analysis of the Boston Naming Test

A number of recent studies utilizing both functional neuroimaging and lesion analysis techniques in neurologic patients have produced conflicting results with respect to the neural correlates of picture naming. Picture naming involves a number of cognitive processes, from visual perception/recognition to lexical-semantic retrieval to articulation. This middle process, the ability to retrieve a name associated with an object, has been attributed in some cases to posterior portions of the left lateral temporal lobe and in other cases, to anterior temporal cortex. In the current study, we used voxel-based lesion symptom mapping (VLSM) to identify neural correlates of picture naming in a large sample of well-characterized left hemisphere (LH) patients suffering from a range of naming deficits. We tested patients on the Boston Naming Test (BNT), a clinical, standardized measure of picture naming that is widely used in both clinical and research settings. We found that overall performance on the BNT was associated with a network of LH regions that included significant portions of the left anterior to posterior middle temporal gyrus (MTG) and superior temporal gyrus (STG) and underlying white matter, and extended into left inferior parietal cortex. However, when we added covariates to this analysis that controlled for deficits in visual recognition and motor speech in order to isolate brain regions specific to lexical-semantic retrieval, the significant regions that remained were confined almost exclusively to the left mid-posterior MTG and underlying white matter. These findings support the notion that a large network in left peri-Sylvian cortex supports picture naming, but that the left mid-posterior MTG and underlying white matter play a critical role in the core ability to retrieve a name associated with an object or picture.

Transcranial magnetic stimulation and aphasia rehabilitation

Repetitive transcranial magnetic stimulation (rTMS) has been reported to improve naming in chronic stroke patients with nonfluent aphasia since 2005. In part 1, we review the rationale for applying slow, 1-Hz, rTMS to the undamaged right hemisphere in chronic nonfluent aphasia patients after a left hemisphere stroke; and we present a transcranial magnetic stimulation (TMS) protocol used with these patients that is associated with long-term, improved naming post-TMS. In part 2, we present results from a case study with chronic nonfluent aphasia where TMS treatments were followed immediately by speech therapy (constraint-induced language therapy). In part 3, some possible mechanisms associated with improvement after a series of TMS treatments in stroke patients with aphasia are discussed.

Treatment of auditory verbal hallucinations with transcranial magnetic stimulation in a patient with psychotic major depression: one-year follow-up

Auditory verbal hallucinations (AVH) in patients with schizophrenia can respond to repetitive transcranial magnetic stimulation (TMS). We report the therapeutic utility of rTMS in a 48-year-old patient with a 20-year history of severe depression (five suicidal gestures and previous failure of ECT) and internal AVH. First, 20 Hz rTMS to the left prefrontal cortex for 3 weeks significantly improved depression (BDI-II: 89% change, lasting 14 months along with weekly/bi-weekly maintenance treatments), but AVH remained unchanged. The patient also underwent a further course of the left temporo-parietal 1 Hz rTMS and amelioration of AVH severity was achieved (PSYRATS-AH: 53% change) and maintained at 1-year follow-up. AVH respond to rTMS in disorders other than schizophrenia. Furthermore, targeted rTMS to different brain regions can address diverse symptoms in neuropsychiatric conditions.

Measuring and inducing brain plasticity in chronic aphasia

Brain plasticity associated with anomia recovery in aphasia is poorly understood. Here, I review four recent studies from my lab that focused on brain modulation associated with long-term anomia outcome, its behavioral treatment, and the use of transcranial brain stimulation to enhance anomia treatment success in individuals with chronic aphasia caused by left hemisphere stroke. In a study that included 15 participants with aphasia who were compared to a group of 10 normal control subjects, we found that improved naming ability was associated with increased left hemisphere activity. A separate study (N = 26) revealed similar results in that improved anomia treatment outcome was associated with increased left hemisphere recruitment. Taken together, these two studies suggest that improved naming in chronic aphasia relies on the damaged left hemisphere. Based on these findings, we conducted two studies to appreciate the effect of using low current transcranial electrical stimulation as an adjuvant to behavioral anomia treatment. Both studies yielded positive findings in that anomia treatment outcome was improved when it was coupled with real brain stimulation as compared with a placebo (sham) condition. Overall, these four studies support the notion that the intact cortex in the lesioned left hemisphere supports anomia recovery in aphasia.

LEARNING OUTCOMES

Readers will (a) be able to appreciate the possible influence of animal research upon the understanding of brain plasticity induced by aphasia treatment, (b) understand where functional changes associated with anomia treatment occur in the brain, (c) understand the basic principles of transcranial direct current stimulation, and (d) understand how brain stimulation coupled with aphasia treatment may potentially improve treatment outcome.

Mechanisms of aphasia recovery after stroke and the role of noninvasive brain stimulation

One of the most frequent symptoms of unilateral stroke is aphasia, the impairment or loss of language functions. Over the past few years, behavioral and neuroimaging studies have shown that rehabilitation interventions can promote neuroplastic changes in aphasic patients that may be associated with the improvement of language functions. Following left hemisphere strokes, the functional reorganization of language in aphasic patients has been proposed to involve both intrahemispheric interactions between damaged left hemisphere and perilesional sites and transcallosal interhemispheric interactions between the lesioned left hemisphere language areas and homotopic regions in the right hemisphere. A growing body of evidence for such reorganization comes from studies using transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), two safe and noninvasive procedures that can be applied clinically to modulate cortical excitability during post-stroke language recovery. We discuss a hierarchical model for the plastic changes in language representation that occur in the setting of dominant hemisphere stroke and aphasia. We further argue that TMS and tDCS are potentially promising tools for enhancing functional recovery of language and for further elucidating mechanisms of plasticity in patients with aphasia.

Transcranial magnetic stimulation in cognitive rehabilitation

Repetitive transcranial magnetic stimulation (rTMS) can generate an increase or a decrease of neuronal excitability, which can modulate cognition and behaviour. Transcranial magnetic stimulation-induced cortical changes have been shown to result in neural plasticity. Thus, TMS provides an important opportunity to gain more insight into the mechanisms responsible for the remarkable flexibility of the central nervous system. The aim of this review was to cover the topics that could be useful when using TMS in the cognitive rehabilitation field after brain damage. The basic TMS principles are introduced, together with the clinical application for diagnosis and prognosis, the biological aspects, and the use in cognitive neuroscience studies. Finally, several hypotheses are discussed to explain the likely mechanisms induced by TMS that favour the recovery of a function after brain damage and cause the adult brain to undergo plasticity. The possibility of non-invasively interacting with the functioning of the brain and its plasticity mechanisms - a possibility that may eventually lead to cognitive and behavioural modifications - opens new and exciting scenarios in the cognitive neurorehabilitation field.

Research with rTMS in the treatment of aphasia

This review of our research with rTMS to treat aphasia contains four parts: Part 1 reviews functional brain imaging studies related to recovery of language in aphasia with emphasis on nonfluent aphasia. Part 2 presents the rationale for using rTMS to treat nonfluent aphasia patients (based on results from functional imaging studies). Part 2 also reviews our current rTMS treatment protocol used with nonfluent aphasia patients, and our functional imaging results from overt naming fMRI scans, obtained pre- and post- a series of rTMS treatments. Part 3 presents results from a pilot study where rTMS treatments were followed immediately by constraint-induced language therapy (CILT). Part 4 reviews our diffusion tensor imaging (DTI) study that examined white matter connections between the horizontal, midportion of the arcuate fasciculus (hAF) to different parts within Broca's area (pars triangularis, PTr; pars opercularis, POp), and the ventral premotor cortex (vPMC) in the RH and in the LH. Part 4 also addresses some of the possible mechanisms involved with improved naming and speech, following rTMS with nonfluent aphasia patients.

Preservation and modulation of specific left hemisphere regions is vital for treated recovery from anomia in stroke

The location and extent of brain changes that support recovery in chronic stroke is probably related to the structural integrity of the remaining cortex. However, little is known about the specifics of this relationship and how it influences treatment outcome in chronic stroke. To examine this issue, the current study examined frank brain damage and changes in cortical activation as predictors of language-treatment outcome in patients with chronic aphasia caused by stroke. Twenty-six patients received multiple MRI sessions before and after 30 h of aphasia treatment targeting anomia, an impairment in the ability to name common objects. Improved naming was associated with increased brain activation in the anterior and posterior regions of the left hemisphere, whereas damage to the posterior portion of the left middle temporal lobe and the temporal-occipital junction had a particularly negative effect on treatment outcome. Specifically, patients whose brain damage included regions commonly associated with lexical retrieval and phonological processing (e.g., Brodmann's areas 37 and 39) were less likely to show treatment-related improvement in correct naming compared with cases where the same areas were intact. These findings suggest that brain changes associated with improved naming ability in chronic aphasia rely on preservation and recruitment of eloquent cortex in the left hemisphere. In general, it seems likely that a similar relationship between cortical preservation and recruitment may also pertain to recovery from other functional impairments in chronic stroke.

Horizontal portion of arcuate fasciculus fibers track to pars opercularis, not pars triangularis, in right and left hemispheres: a DTI study

The arcuate fasciculus (AF) is a white matter pathway traditionally considered to connect left Broca's area with posterior language zones. We utilized diffusion tensor imaging (DTI) in eight healthy subjects (5 M) to track pathways in the horizontal mid-portion of the AF (hAF) to subregions of Broca's area - pars triangularis (PTr) and pars opercularis (POp); and to ventral premotor cortex (vPMC) in the right and left hemispheres (RH, LH). These pathways have previously been studied in the LH, but not in the RH. Only 1/8 subjects showed fiber tracts between PTr and hAF in the RH (also, only 1/8 in the LH). In contrast to PTr, 5/8 subjects showed fiber tracts between POp and hAF in the RH (8/8 in the LH). Fiber tracts for vPMC were similar to those of POp, where 7/8 subjects showed fiber tracts between vPMC and hAF in the RH (8/8 in the LH). Our designated hAF could have included some of the superior longitudinal fasciculus (SLF) III, because it is difficult to separate the two fiber bundles. The SLF III has been previously reported to connect supramarginal gyrus with POp and vPMC in the LH. Thus, although the present DTI study showed almost no pathways between PTr and hAF in the RH (and in the LH), robust pathways were observed between POp and/or vPMC with hAF in the RH (and in LH). These results replicate previous studies for the LH, but are new, for the RH. They could contribute to better understanding of recovery in aphasia.