Posts Tagged aphasia

[REVIEW] Repetitive transcranial magnetic stimulation in stroke rehabilitation: review of the current evidence and pitfalls – Full Text

Acute brain ischemia causes changes in several neural networks and related cortico-subcortical excitability, both in the affected area and in the apparently spared contralateral hemisphere. The modulation of these processes through modern techniques of noninvasive brain stimulation, namely repetitive transcranial magnetic stimulation (rTMS), has been proposed as a viable intervention that could promote post-stroke clinical recovery and functional independence. This review provides a comprehensive summary of the current evidence from the literature on the efficacy of rTMS applied to different clinical and rehabilitative aspects of stroke patients. A total of 32 meta-analyses published until July 2019 were selected, focusing on the effects on motor function, manual dexterity, walking and balance, spasticity, dysphagia, aphasia, unilateral neglect, depression, and cognitive function after a stroke. Only conventional rTMS protocols were considered in this review, and meta-analyses focusing on theta burst stimulation only were excluded. Overall, both HF-rTMS and LF-rTMS have been shown to be safe and well-tolerated. In addition, the current literature converges on the positive effect of rTMS in the rehabilitation of all clinical manifestations of stroke, except for spasticity and cognitive impairment, where definitive evidence of efficacy cannot be drawn. However, routine use of a specific paradigm of stimulation cannot be recommended yet due to a significant level of heterogeneity of the studies in terms of protocols to be set and outcome measures that have to be used. Future studies need to preliminarily evaluate the most promising protocols before going on to multicenter studies with large cohorts of patients in order to achieve a definitive translation into daily clinical practice.

Background

Stroke is a common acute neurovascular disorder that causes disabling long-term limitations to daily living activities. The most common consequence of a stroke is motor deficit of variable degree,1 although nonmotor symptoms are also relevant and often equally disabling.2 To date, to the best of the authors’ knowledge, there is no validated treatment that is able to restore the impaired functions by a complete recovery of the damaged tissue. Indeed, stroke management basically consists of reducing the initial ischemia in the penumbra, preventing future complications, and promoting a functional recovery using physiotherapy, speech therapy, occupational therapy, and other conventional treatments.3,4

Ischemic damage is associated with significant metabolic and electrophysiological changes in cells and neural networks involved in the affected area. From a pure electrophysiological perspective, however, beyond the affected area, there is a local shift in the balance between the inhibition and excitation of both the affected and contralateral hemisphere, consisting of increased excitability and disinhibition (reduced activity of the inhibitory circuits).3,5 In addition, subcortical areas and spinal regions may be altered.3,5 In particular, the role of the uninjured hemisphere seems to be of utmost significance in post-stroke clinical and functional recovery.

Different theoretical models have been proposed to explain the adaptive response of the brain to acute vascular damage. According to the vicariation model, the activity of the unaffected hemisphere contributes to the functional recovery after a stroke through the replacement of the lost functions of the affected areas. The interhemispheric competition model considers the presence of mutual inhibition between the hemispheres, and the damage caused by a stroke disrupts this balance, thus producing a reduced inhibition of the unaffected hemisphere by the affected side. This results in increased inhibition of the affected hemisphere by the unaffected side. More recently, a new model, called bimodal balance recovery, has been proposed.3,5 It introduces the concept of a structural reserve, which describes the extent to which the nondamaged neural pathways contribute to the clinical recovery. The structural reserve determines the prevalence of the interhemispheric imbalance over vicariation. When the structural reserve is high, the interhemispheric competition model can predict the recovery better than the vicariation model, and vice versa.3

Repetitive transcranial magnetic stimulation

One of the proposed interventions to improve stroke recovery, by the induction of neuromodulation phenomena, is based on methods of noninvasive brain stimulation. Among them, transcranial magnetic stimulation (TMS) is a feasible and painless neurophysiological technique widely used for diagnostic, prognostic, research, and, when applied repetitively, therapeutic purposes.69 By electromagnetic induction, TMS generates sub or suprathreshold currents in the human cortex in vivo and in real time.10,11

The most common stimulation site is the primary motor cortex (M1), that generates motor evoked potentials (MEPs) recorded from the contralateral muscles through surface electromyography electrodes.11 The intensity of TMS, measured as a percentage of the maximal output of the stimulator, is tailored to each patient based on the motor threshold (MT) of excitability. Resting MT (rMT) is found when the target muscle is at rest, it is defined as the minimal intensity of M1 stimulation required to elicit an electromyography response with a peak-to-peak amplitude > 50 µV in at least 5 out of 10 consecutive trials.11 Alternatively TMS MTAT 2.0 software (http://www.clinicalresearcher.org/software.htm) is a free tool for TMS researchers and practitioners. It provides four adaptive methods based on threshold-tracking algorithms with the parameter estimation by sequential testing, using the maximum-likelihood strategy for estimating MTs. Active MT (aMT) is obtained during a tonic contraction of the target muscle at approximately 20% of the maximal muscular strength.11

The rMT is considered a basic parameter in providing the global excitation state of a central core of M1 neurons.11 Accordingly, rMT is increased by drugs blocking the voltage-gated sodium channels, where the same drugs may not have an effect on the gamma-aminobutyric acid (GABA)-ergic functions. In contrast, rMT is reduced by drugs increasing glutamatergic transmission not mediated by the N-methyl-D-aspartate (NMDA) receptors, suggesting that rMT reflects both neuronal membrane excitability and non-NMDA receptor glutamatergic neurotransmission.12 Finally, the MT increases, being often undetectable, when a substantial portion of M1 or the cortico-spinal tract is damaged (i.e. by stroke or motor neuron disease), and decreases when the motor pathway is hyperexcitable (such as epilepsy).13

Repetitive (rTMS) is a specific stimulation paradigm characterized by the administration of a sequence of consecutive stimuli on the same cortical region, at different frequencies and inter sequence intervals. As known, rTMS can transiently modulate the excitability of the stimulated cortex, with both local and remote effects outlasting the stimulation period. Conventional rTMS modalities include high-frequency (HF-rTMS) stimulation (>1 Hz) and low-frequency (LF-rTMS) stimulation (⩽1 Hz).11 High-frequency stimulation typically increases motor cortex excitability of the stimulated area, whereas low-frequency stimulation usually produces a decrease in excitability.14 The mechanisms by which rTMS modulates the brain are rather complex, although they seem to be related to the phenomena of long-term potentiation (LTP) and long-term depression (LTD).15

When applied after a stroke, rTMS should ideally be able to suppress the so called ‘maladaptive plasticity’16,17 or to enhance the adaptive plasticity during rehabilitation. These goals can be achieved by modulating the local cortical excitability or modifying connectivity within the neuronal networks.10

rTMS in stroke rehabilitation: an overview

According to the latest International Federation of Clinical Neurophysiology (IFCN) guidelines on the therapeutic use of rTMS,10 there is a possible effect of LF-rTMS of the contralesional motor cortex in post-acute motor stroke, and a probable effect in chronic motor stroke. An effect of HF-rTMS on the ipsilesional motor cortex in post-acute and chronic motor stroke is also possible.

The potential role of rTMS in gross motor function recovery after a stroke has been assessed in a recent comprehensive systematic review of 70 studies by Dionisio and colleagues.18 The majority of the publications reviewed report a role of rTMS in improving motor function, although some randomized controlled trials (RCTs) were not able to confirm this result,1923 as shown by a recent large randomized, sham-controlled, clinical trial of navigated LF-rTMS.24 It has also been suggested that rTMS can specifically improve manual dexterity,10 which is defined as the ability to coordinate the fingers and efficiently manipulate objects, and is of crucial importance for daily living activities.25 Notably, most of the studies focused on motor impairment in the upper limbs, whereas limited data is available on the lower limbs.18 Walking and balance are frequently impaired in stroke patients and significantly affect the quality of life (QoL),26,27 and rTMS might represent a valid aid in the recovery of these functions.28,29 Spasticity is another common complication after a stroke, consisting of a velocity-dependent increase of muscular tone,30 and for which rTMS has been proposed as a rehabilitation tool.31

Dysphagia is highly common in stroke patients, it impairs the global clinical recovery, and predisposes to complications.32 It has been pointed out that rTMS targeting the M1 area representing the muscles involved in swallowing may contribute to the treatment of post-stroke dysphagia.33

Nonmotor deficit is also a relevant post-stroke disability that negatively impacts the QoL. Aphasia is a very common consequence of stroke, affecting approximately 30% of stroke survivors and significantly limiting rehabilitation.34 According to the IFCN guidelines, to date, there is no recommendation for LF-rTMS of the contralesional right inferior frontal gyrus (IFG). Similarly, no recommendation for HF-rTMS or intermittent theta burst stimulation (TBS) of the ipsilesional left IFG or dorsolateral prefrontal cortex (DLPFC) in Broca’s aphasia has been currently approved.10 The same is true for LF-rTMS of the right superior temporal gyrus in Wernicke’s aphasia.10

Neglect is the incapacity to respond to tactile or visual contralateral stimuli that are not caused by a sensory-motor deficit.35 Although hard to treat, rTMS has been proposed as a tool for neglect rehabilitation.36 However, the IFCN guidelines state that currently there is no recommendation for LF-rTMS of the contralesional left posterior parietal cortex, or for HF-rTMS of the ipsilesional right posterior parietal cortex.10 In a recent systematic review, most of the included studies supported the use of TMS for the rehabilitation of aphasia, dysphagia, and neglect, although the heterogeneity of stimulation protocols did not allow definitive conclusions to be drawn.37

Post-stroke depression is a relevant complication of cerebrovascular diseases.38 The role of rTMS in the management of major depressive disorders is well documented,39,40 and currently, rTMS is internationally approved and indicated for the treatment of major depression in adults with antidepressant medication resistance, and in those with a recurrent course of illness, or in cases of moderate-to-severe disease severity.39 In major depression disorders, according to the IFCN guidelines, there is a clear antidepressant effect of HF-rTMS over the left DLPFC, a probable antidepressant effect of LF-rTMS on the right DLPFC, and probably no differential antidepressant effect between right LF-rTMS and left HF-rTMS. Moreover, there is currently no recommendation for bilateral stimulation combining HF-rTMS of the left DLPFC and LF-rTMS of the right DLPFC. The mentioned guidelines also state that the antidepressant effect when stimulating DLPFC is probably additive, and possibly potentiating, to the efficacy of antidepressant drugs.10 However, no specific recommendation currently addresses the use of rTMS in post-stroke depression. Recently, rTMS has been proposed as a treatment option for the late-life depression associated with chronic subcortical ischemic vascular disease, the so called ‘vascular depression’.4144 Three studies tested rTMS efficacy in vascular depression (one was a follow-up study with citalopram). Although presenting positive findings, further trials should refine clinical and diagnostic criteria to assess its impact on antidepressant efficacy.45

Approximately 25–30% of stroke patients develop an immediate or delayed cognitive impairment or an overt picture of vascular dementia.46 There is evidence of an overall positive effect on cognitive function for both LF-rTMS47 and HF-rTMS,48 supported by studies on experimental models of vascular dementia.4952 Nonetheless, the few trials examining the effect on stroke-related cognitive deficit produced mixed results.5356 In particular, two studies found no effect on cognition when stimulating the left DLPFC at 1 Hz and 10 Hz,53,54 whereas a pilot study found a positive effect on the Stroop interference test with HF-rTMS over the left DLPFC in patients with vascular cognitive impairment without dementia.55 However, this finding was not replicated in a follow-up study.56 To summarize, rTMS can induce beneficial effects on specific cognitive domains, although data are limited and their clinical significance needs to be further validated. Major challenges exist in terms of appropriate patient selection and optimization of the stimulation protocols.57

Central post-stroke pain (CPSP) is the pain resulting from an ischemic lesion of the central nervous system.58 It represents a relatively common complication after a stroke, although it is often under-recognized and, therefore, undertreated.59 According to the IFCN guidelines for the use of rTMS in the treatment of neuropathic pain, there is a definite analgesic effect of HF-rTMS of contralateral M1 to the pain side, and LF-rTMS of contralateral M1 to the pain side is probably ineffective. In addition, there is currently no recommendation for cortical targets other than contralateral M1 to the pain side.10 Notably, rTMS might be effective in drug-resistant CPSP patients.58 A recent systematic review that included nine HF-rTMS studies suggested an effect on CPSP relief, but also underlined the insufficient quality of the studies considered.60

Study objective

In this article, we aim to provide an up-to-date overview of the most recent evidence on the efficacy of rTMS in the rehabilitation of stroke patients. Although several studies have been published, a conclusive statement supporting a systematic use of rTMS in the multifaceted clinical aspects of stroke rehabilitation is still lacking.

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Continue —> Repetitive transcranial magnetic stimulation in stroke rehabilitation: review of the current evidence and pitfalls – Francesco Fisicaro, Giuseppe Lanza, Alfio Antonio Grasso, Giovanni Pennisi, Rita Bella, Walter Paulus, Manuela Pennisi, 2019

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[WEB SITE] Communication problems after brain injury

Communication problems after brain injury are very common. Although most of us take it for granted, the ability to communicate requires extremely complex skills and many different parts of the brain are involved.

There are four main categories of the effects of brain injury. Any of these can cause communication problems:

  • Physical – affecting how the body works
  • Cognitive – affecting how the person thinks, learns and remembers
  • Emotional – affecting how the person feels
  • Behavioural – affecting how a person acts

Many people will experience more than one form of communication problem after brain injury, depending on the areas of the brain affected and the severity of the injury. It is also important to recognise that such problems may occur alongside other changes in physical, cognitive, emotional and behavioural functions.

The diagram below shows the cerebral cortex. The cortex is the outer part of the brain, which is responsible for our more sophisticated thinking skills. Many of the functions listed are important for communication and injury to any of these areas can impair communication skills.

This section explains some of the ways brain injury can affect communication.

  • Language impairment – aphasia (often called dysphasia)
    Covers problems with understanding language and expressing thoughts through language. Also covers problems with reading and writing.
  • Speech difficulties
    Discusses disorders of speech that can occur after brain injury.
  • Cognitive communication difficulties
    Covers some of the problems with communication caused by cognitive difficulties, such as memory impairment, attention difficulties, poor social skills and fatigue.

Our booklet Coping with communication problems after brain injury provides more in-depth information about the issues covered here, and you can contact the Headway helpline if you have any further questions.

via Communication problems | Headway

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[NEWS] New Study Suggests Benefits of Digital Therapy for Stroke Patients – Rehab Managment

Published on 

ConstantTherapy

A large scale retrospective study of post-stroke rehabilitation practices compares outcomes among patients using tablet-based therapy at home and those who complete the same therapy in a clinic.

The study, published in Frontiers in Neurology, analyzed data from 3,686 Constant Therapy users—patients with post-stroke aphasia—over a 4-year period (2013-2017).

In the study, home users and clinic users completed cognitive and language tasks such as Functional Math, Name Pictures, Map Reading, and Auditory Commands that are featured in the Constant Therapy app. Home users worked independently while clinic users worked under the guidance of a clinician. The study compared improvement rates for both groups, who were initially struggling with a task (less than 60% accuracy) but eventually mastered it (more than 90% accuracy), explains a media release from The Learning Corp.

Key findings include:

  • Home users took less time to master tasks than users who only practiced in the clinic. While both home and clinic users required roughly the same amount of practice to master cognitive and language tasks, users who had on-demand access to therapy on their tablet mastered tasks in a median of six days, while those with only in-clinic access mastered tasks in a median of 12 days.
  • Home users practiced therapy more frequently than clinic users. Users who had access to digital therapy on their own terms took advantage of practicing at home at least every two days, while clinic users practiced in the clinic just once every five days.
  • Improvements are possible long after a stroke has occurred. Thousands of people in the study, regardless of where they practiced, showed significant gains in language and cognitive skills even though their stroke occurred long ago (on average two years ago for home users and average of 1.6 years ago for clinic users).
  • Improvements aren’t just for the young. While the average age of home users was 60 years old and the average age of clinic users was 64 years old, nearly one third (29%) of users were 71 years old or more, and the oldest user was 97 years old.

Veera Anantha, president and CTO of The Learning Corp, suggests that the study’s findings show that home users who practice often can also progress quickly, which may mean they are ready to work on more challenging tasks in their next home or clinic session.

“These insights from real world patient experience could help update existing guidelines and highlight areas for future study to uncover how improvements in specific tasks can help people living post-stroke regain the skills they cherish, such as reading a newspaper, having a complete conversation, or ordering from a menu at a restaurant,” Anantha states.

A previous study published in Frontiers in Human Neuroscience examined the effectiveness of Constant Therapy among a group of 51 patients. It provided preliminary evidence for the usefulness of a tablet-based platform to deliver tailored language and cognitive therapy to individuals with aphasia, per the release.

[Source(s): The Learning Corp, Business Wire]

 

via New Study Suggests Benefits of Digital Therapy for Stroke Patients – Rehab Managment

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[WEB SITE] Recovering From A Left Side Stroke – Saebo

Have you ever heard someone describe themselves as “right-brained” or “left-brained”? This concept is based on the brain having two hemispheres that perform different, specialized functions. Creative types have a dominant right brain, while analytical people favor the left. It is necessary to understand the functions of both hemispheres when assessing consequences of neurological damage. This knowledge helps anticipate problems that might occur and customize strategies for recovery.

Although the brain is divided into two hemispheres, they work in tandem to absorb information and process details. For instance, visual signals are sent to the right hemisphere first, but the left hemisphere uses context from past experiences to comprehend what the right brain has “seen”.

A left-brain stroke comes with a particular set of symptoms, changes, and challenges. An understanding of these consequences may ease the frustrations of stroke survivors and their families during the recovery process.

What Does The Left Brain Control?

The left hemisphere is responsible for controlling the logic of information processing. Common functions of the left hemisphere include the following:

  • Language
  • Critical thinking and analysis
  • Judgment and reasoning
  • Decision-making
  • Mathematics and sequencing

In a way, the left hemisphere processes information in words and numbers, as opposed to images, as the right hemisphere does. This lends to the common belief that “right-brain thinkers” are often more “creative” types, while left-brain thinkers are more analytical and mathematical.

Possible Effects Of A Left-Brain Stroke

Motor Impairment

On a physical level, the left hemisphere controls the right side of the body, and vice versa. Most physical impairments and paralysis after a stroke stem from issues in the brain, not in the impaired limb itself. Right-sided limbs are likely to suffer complications after a left-brain stroke, possibly resulting in hemiplegia—the paralysis of one side of the body.

Those recovering from a stroke may experience paralysis in certain limbs, and/or less severe symptoms including motor function impairment, muscle weakness, and spasticity. A combination of impairments can make daily life more challenging, both physically and psychologically.

Aphasia

Since the left hemisphere bears most of the responsibility for receiving and deciphering language, a left-brain stroke can often impair both speech production and the interpretation of word-based information. These impairments are collectively known as aphasia, and the consequences for everyday life depend on the type of aphasia experienced.

There are two main types of aphasia:

  1. Receptive aphasia complicates the brain’s reception and interpretation of words from speech or text. An individual with receptive aphasia may experience a range of confusion, from missing a word here or there to needing things repeated several times before they are comprehended. Left-brain stroke survivors may respond best to simpler words and direct, one-on-one conversations. Excessive distractions or multiple people speaking at once may inhibit comprehension. A survivor may find it easier to read short sentences, while complicated sentences and large paragraphs may cause frustration.
  2. Expressive aphasia complicates the spoken or written expression of thoughts. The exact manifestation will vary from person to person. At times, an individual with expressive aphasia may leave words out of long sentences, use words they don’t intend to say, or even use incomprehensible sounds instead of words. Changes in pace and inflection are also indicative of this.

The effects of aphasia become particularly complex when stroke survivors try to express their needs, especially during the initial stages of recovery. Someone may intend to ask for water but end up asking for something else entirely because they cannot find the right words. Depending on where the neurological damage occurred, stroke survivors may experience a combination of both types of aphasia.

Intellectual Impairment

Since analytical tasks default to the left hemisphere, a left-brain stroke may impair the management of common household and daily activities. Paying bills, handling money, or taking care of other analytical tasks may become more difficult. The stroke survivor may become dependent on family or a caretaker to complete important organizational tasks.

Behavioral Changes

It is common for those with left-brain injuries to process information more slowly and therefore move with more caution. Rushing may cause confusion or even injury. The inability to move quickly may lead to frustration and even periods of anger or depression.

Visual Impairment

Vision issues are particularly common in the right eye after a left-brain stroke. Potential problems include drooping of the eyelid and impaired blood flow to the retina. The stroke survivor may experience hemianopia, or blindness in half of the visual field.

Agnosia—the inability to recognize and name items—may also occur for the same reasons that produce aphasia. An injury to brain regions that manage naming and recognition may prevent the survivor from identifying common items, adding a sensation of foreignness and confusion to daily life.

Recovering From A Left-Brain Stroke

Though changes after a left-brain stroke are often abrupt and severe, the brain has an incredible ability to adjust and even reconnect neurological pathways. This ability is called neuroplasticity and occurs before you’re even born. Throughout childhood and adulthood, new pathways form as new information is absorbed by the brain. After an injury, the brain’s neuroplasticity can be sparked to form new neurons and connections through the repetition of targeted rehabilitation exercises. It is only through this constant repetition that the brain rewires and brings to life the lost connections.

Exercises that focus on the right side of the body and reinforce analytical reasoning are the most effective methods to support the regrowth of neurological pathways in the left hemisphere. After all, the body and mind are forever learning. This is true even if portions of the brain are no longer fully functional. Neural functions can adjust and change, for the better, through the support of ongoing rehabilitation.

All content provided on this blog is for informational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. If you think you may have a medical emergency, call your doctor or 911 immediately. Reliance on any information provided by the Saebo website is solely at your own risk.

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[Review] Current evidence on transcranial magnetic stimulation and its potential usefulness in post-stroke neurorehabilitation: Opening new doors to the treatment of cerebrovascular disease – Full Text

Abstract

Introduction

Repetitive transcranial magnetic stimulation (rTMS) is a therapeutic reality in post-stroke rehabilitation. It has a neuroprotective effect on the modulation of neuroplasticity, improving the brain’s capacity to retrain neural circuits and promoting restoration and acquisition of new compensatory skills.

Development

We conducted a literature search on PubMed and also gathered the latest books, clinical practice guidelines, and recommendations published by the most prominent scientific societies concerning the therapeutic use of rTMS in the rehabilitation of stroke patients. The criteria of the International Federation of Clinical Neurophysiology (2014) were followed regarding the inclusion of all evidence and recommendations.

Conclusions

Identifying stroke patients who are eligible for rTMS is essential to accelerate their recovery. rTMS has proven to be safe and effective for treating stroke complications. Functional brain activity can be optimised by applying excitatory or inhibitory electromagnetic pulses to the hemisphere ipsilateral or contralateral to the lesion, respectively, as well as at the level of the transcallosal pathway to regulate interhemispheric communication. Different studies of rTMS in these patients have resulted in improvements in motor disorders, aphasia, dysarthria, oropharyngeal dysphagia, depression, and perceptual-cognitive deficits. However, further well-designed randomised controlled clinical trials with larger sample size are needed to recommend with a higher level of evidence, proper implementation of rTMS use in stroke subjects on a widespread basis.

Introduction

Stroke patients should receive early neurorehabilitation after convalescence. For many years, researchers have aimed to identify new therapeutic targets to hasten recovery from stroke. However, we continue to lack a universally accepted, approved pharmacological therapy for these patients.1234 ;  5 After stroke, organisational changes in brain interneuronal activity in the affected area and the surrounding healthy tissue may on occasion promote functional recovery. Neurorehabilitation may help achieve this aim. Unfortunately, there are also occasions when neural reorganisation is suboptimal; in these cases, the problem persists and becomes chronic. In this context, transcranial magnetic stimulation (TMS) emerged as a tool for studying the brain and has been used since the mid-1980s to treat certain neuropsychiatric disorders. Neurorehabilitation is based on the idea that the brain is a dynamic entity able to adapt to internal and external homeostatic changes. This adaptive capacity, called neuroplasticity, is also present in patients with acquired brain injuries. The degree of recovery and the functional prognosis of these patients depend on the extent of neuroplastic changes.12345 ;  6 When performed by experienced physicians, TMS is a safe, non-invasive technique which enables the organisation of these neural changes (Fig. 1). The technique’s applications are expanding rapidly.12345678 ;  9

Modern TMS device.

Figure 1.

Modern TMS device.

We present the results of a literature review of the most relevant articles, manuals, and clinical practice guidelines addressing TMS (background information, diagnostic and therapeutic uses, and especially its usefulness for stroke neurorehabilitation) and published between 1985 (when the technique was first used) and 2015.

 

Development

The organisation of language in the brain

The left hemisphere of the brain is the anatomo-functional seat of language in 96% of right-handed and 70% of left-handed individuals. Language processing in the left hemisphere involves certain anatomical pathways for language comprehension, repetition, and production (Fig. 2). Positron emission tomography and functional magnetic resonance imaging (fMRI) studies conducted during multiple language tasks have shown brain activation not only in the main language centres (lesions to these areas may cause Broca aphasia, Wernicke aphasia, etc.) (Fig. 3) but also in many other locations, such as the thalamus (alertness), the basal ganglia (motor modulation), and the limbic system (affect and memory). Language is the perfect model for understanding how the central nervous system works as a whole.10 ;  11

Figure 2. The functional pathways involved in comprehension, repetition, and production of written, gesture, and spoken language, according to the Wernicke-Geschwind model. Within the left hemisphere, language organisation follows certain anatomical pathways for language comprehension, repetition, and production. Sounds are processed by the bilateral auditory cortex, in the superior temporal gyrus (primary auditory area), and decoded in the posterior area of the left temporal cortex (Wernicke area); the latter is connected to other cortical areas or networks which assign meaning to words. During reading, output from the primary visual area (bilaterally) travels to other parieto-occipital association areas for word and phrase recognition (especially the left fusiform gyrus, located in the inferior surface of the temporal lobe, where there is a key word recognition centre) and reaches the angular gyrus, which processes language-related visual and auditory information. In spontaneous language repetition and production, auditory information must travel through the arcuate fasciculus towards the left inferior frontal region (Broca area), which is responsible for language production; this area is also known to be involved in such other functions as action comprehension (mirror neurons). To produce written or spoken language, output from the Wernicke area, the Broca area, and nearby association areas must reach the primary motor cortex.10 ;  11
Adapted with permission from Bear et al.10

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Continue —> Current evidence on transcranial magnetic stimulation and its potential usefulness in post-stroke neurorehabilitation: Opening new doors to the treatment of cerebrovascular disease

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[Abstract] Low-frequency rTMS of the unaffected hemisphere in stroke patients: A systematic review

Abstract

The aim of this review was to summarize the evidence for the effectiveness of low-frequency (LF) repetitive transcranial magnetic stimulation (rTMS) over the unaffected hemisphere in promoting functional recovery after stroke. We performed a systematic search of the studies using LF-rTMS over the contralesional hemisphere in stroke patients and reviewed the 67 identified articles. The studies have been gathered together according to the time interval that had elapsed between the stroke onset and the beginning of the rTMS treatment. Inhibitory rTMS of the contralesional hemisphere can induce beneficial effects on stroke patients with motor impairment, spasticity, aphasia, hemispatial neglect and dysphagia, but the therapeutic clinical significance is unclear. We observed considerable heterogeneity across studies in the stimulation protocols. The use of different patient populations, regardless of lesion site and stroke aetiology, different stimulation parameters and outcome measures means that the studies are not readily comparable, and estimating real effectiveness or reproducibility is very difficult. It seems that careful experimental design is needed and it should consider patient selection aspects, rTMS parameters and clinical assessment tools. Consecutive sessions of rTMS, as well as the combination with conventional rehabilitation therapy, may increase the magnitude and duration of the beneficial effects. In an increasing number of studies, the patients have been enrolled early after stroke. The prolonged follow-up in these patients suggests that the effects of contralesional LF-rTMS can be long-lasting. However, physiological evidence indicating increased synaptic plasticity, and thus, a more favourable outcome, in the early enrolled patients, is still lacking. Carefully designed clinical trials designed are required to address this question. LF rTMS over unaffected hemisphere may have therapeutic utility, but the evidence is still preliminary and the findings need to be confirmed in further randomized controlled trials.

Source: Low-frequency rTMS of the unaffected hemisphere in stroke patients: A systematic review – Sebastianelli – 2017 – Acta Neurologica Scandinavica – Wiley Online Library

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[WEB SITE] Life after stroke: Tips for recovering communication skills – Medical News Today

Every year in the United States, more than 795,000 people have a stroke, according to the Centers for Disease Control and Prevention. Furthermore, the United Kingdom’s Stroke Association note that 1 in 3 people will experience communication problems after a stroke.
[stroke]
Stroke can lead to ongoing communication problems, but recovery is often possible.

Unfortunately, we often judge people on how well they communicate. From the outside, a person who has difficulty speaking may appear to have difficulty thinking, too, but this is not necessarily true.

For a person who has had a stroke, the ability to think and communicate depends on the part, or parts, of the brain that have been affected.

Having a stroke can be a frightening and frustrating experience. Not being able to tell people what is going on in the aftermath can extend the trauma.

Friends and family members, for their part, can also find themselves tongue-tied. They may feel embarrassed, lost for words, or they may think that this is no longer the person they once knew.

Post-stroke rehabilitation can help people to regain some or all of their skills. Speech therapists specialize in communication, but nonspecialists can also play a key role.

It is important for friends and relatives to understand that what a person expresses on the outside, after a stroke, is not necessarily what is going on in their head. They should also remember that, although a person faces new challenges after experiencing a stroke, they are still the same person.

This article will offer some tips from people who have “been there” that can give us the necessary skills for helping someone get back to communicating after a stroke.

How does a stroke affect communication?

A stroke is a brain injury that results from bleeding or a blockage in the brain. The effects can be sudden or gradual, and the damage may impact various aspects of mental and physical health.

These include:

  • Motor skills
  • The senses, including reactions to pain
  • Language
  • Thinking and memory
  • Emotions.

A stroke can affect a person’s use of language in a variety of ways.

Not only can the processing of language be impaired, but paralysis or physical weakness in the face, tongue, or throat muscles could make it hard to swallow, control breathing, and form sounds.

The type and extent of communication problems will depend on the form of stroke and what kind of injury has occurred. The damage and resulting levels of ability will also vary.

The Stroke Association describe three conditions that affect communication after a stroke: aphasia, dysarthria, and dyspraxia. A person may experience one or a combination of these.

Aphasia

Aphasia, or dysphasia, results from damage to one of the “language control centers” in the brain. While it influences communication, it does not impact intelligence. It may affect just one type of communication – for example, reading, listening or speaking, or a combination.

Fast facts about stroke

  • Stroke can lead to paralysis or weakness on one side of the body
  • There may be difficulty with thinking, awareness, attention, learning, judgment, and memory
  • It can be hard to understand or form speech
  • Mood and emotions can be affected.

Learn more about stroke

Damage to a part of the brain known as Wernicke’s area can lead to receptive aphasia.

This makes it difficult to understand long and complex sentences, especially if there is background noise, or if more than one person is talking. The person may feel as if others are speaking in a foreign language. Their own speech may also become incoherent.

If there is damage to Broca’s area, expressive aphasia can result.

The person can understand others, but they will be unable to explain themselves. They can think the words, but they cannot speak them or put them together in order to make coherent, grammatically correct sentences.

A person with expressive aphasia may be able to make sounds or say short words or parts of sentences, but they may miss out important words or use the wrong word. They might have the word “on the tip of the tongue,” but not be able to get it out.

It may seem to the speaker that they are talking normally, but to a listener, it can sound like nonsense. Listeners may believe that the speaker is confused when they are not. They just cannot get the ideas across.

Damage that affects multiple areas of the brain can lead to mixed, or global, aphasia with challenges in all aspects of communication. The person may no longer use language to convey thought.

Dysarthria and dyspraxia

Dysarthria and dyspraxia relate to the physical production of speech sounds.

A person with dysarthria can find the words, but they cannot form them because of a physical problem, such as muscular weakness. This may cause the words to come out slurred or in short bursts. This slurring does not necessarily reflect the person’s state of mind. It is likely that only their ability to communicate is limited.

Dyspraxia involves difficulty with movement and coordination, so that the muscles needed for speech sounds may not work properly or in the correct order. This, too, can affect speech.

Other changes

Other changes that can make it hard to contribute to conversations include:

  • A loss of voice tone, normally used to express emotions
  • Fixed facial expression
  • Problems understanding humor
  • Inability to take turns in conversation.

These can make the person appear depressed, even if they are not.

Some people are aware that they are experiencing these changes. If so, letting others know what the problem is can help to combat the issue.

However, a person with anosognosia will be unable to recognize that anything is wrong, due to a lack of insight resulting from damage to the brain. This can hinder recovery.

Further problems

Depending on the damage that has occurred, vision and hearing problems can also affect communication and writing ability.

Tiredness is a common result of stroke. Conversation might also be tiring, because it demands so much effort.

After a stroke, stress and personality changes can occur. Stress can exacerbate communication problems, especially if the person becomes impatient with themselves, or if others become impatient.

Mood changes, due to the stroke’s effect on the brain, can further add to the strain.

What does a speech therapist do?

Speech therapy is a key part of rehabilitation after a stroke.

A speech therapist will help people with swallowing; this can be severely impaired, and it has an impact on language production.

[speech therapy]
Speech therapy can involve practicing forming words.

Language practice activities that speech therapists may use include intensive exercises in:

  • Repeating words
  • Following directions
  • Reading and writing.

Examples of more extensive practice are:

  • Conversational coaching
  • Rehearsing speech
  • Developing prompts to help people remember specific words
  • Working out ways to get around language disabilities, such as using symbols and sign language.

Communication technology has expanded the range of ways to practice and improve communication. An example of this is pressing a key to activate a voice simulator.

Some tips from people with first-hand experience

Medical News Today asked two men, Peter Cline and Geoff, about their experience in regaining communication skills after a stroke. Peter, an engineer, had a stroke at the age of 59 when he was just starting a holiday in Tasmania. Geoff, who ran his own business until his retirement, was living in Spain when he became ill.

Both men have worked hard to regain their communication skills.

We asked what advice they would give people in order to help them communicate with someone following a stroke.

They gave us this list of dos:

[singing group]
Songs help some people to relax and communicate.
  • Do look directly at the person when you are speaking to them
  • Do speak slowly and clearly, but use a normal tone of voice
  • Do use short sentences and stick to one topic at a time
  • Do ensure there is no background noise
  • Do reassure the person that you understand their frustration
  • Do write things down, if it will help
  • Do find out about the person’s employment, interests and passions – now and before the stroke – and try to relate to these
  • Do give people a chance to say what they want to say, without jumping in or correcting them.

They also gave us some don’ts:

  • Don’t finish the person’s sentences for them
  • Don’t speak too fast
  • Don’t push them too much
  • Don’t speak to the person while they are driving, for example, because they cannot concentrate
  • Don’t assume that because the person is having difficulty understanding, they must be stupid
  • Don’t “talk down” to the person, or speak to them as if they are a child
  • Don’t keep “rabbiting.”

Geoff told MNT that he feels his communication skills “go up and down.” It becomes harder for him to communicate when he is tired, and when there are more than two people in the conversation.

Both Geoff and Peter have made remarkable progress in their communication skills, and they each offered some words of encouragement for people who have had a stroke.

Geoff’s advice is:

“Take time to recover, and, when communicating, take time to explain, and don’t let yourself feel rushed.”

Peter says:

  • Persevere and don’t give up. Things will gradually improve but not as quickly as you want them to
  • Expect peaks and troughs in your recovery
  • Enjoy relaxing with something you are familiar with, for example, old films, music, or whatever your “comforter” is.

Peter explains that after a stroke, an individual can feel as if they are inside a bubble. “It helps if you can get someone to understand that,” he says.

Activities that can help

Friends and family can engage in regular practice activities to help someone recover their communication skills after a stroke.

It may be helpful to arrange regular slots for communication practice, at a time when the person will not be tired.

Here are some activities for sharing, depending on individual styles and taste:

[photo album and conversation]
A photo album can be useful for prompting conversation.
  • Songs, especially if the person was a keen singer before. Some people can sing after a stroke, even if they cannot speak, because singing and speaking use different parts of the brain
  • Card games that involve the person saying the name of the card
  • A photo album, to share and discuss the people and events in the pictures
  • A personal file, with information about the person’s life, jobs, and family, in order to provide topics of conversation and nonverbal clues when access to key words is difficult
  • A diary, with records of visits, events, and conversations. Friends and family can be encouraged to write in it, to help the person track their progress
  • News stories to read in advance and discuss during the session.

If an important conversation is coming up – with the insurance company or hospital, for example – these slots can be a good place to prepare.

Other tips for self-help

If a person has difficulty expressing a word or idea, encouraging them to write or draw what they mean can help. Some people can spell a word, even if they cannot say it.

Strategies that people have used to practice alone include:

  • Rehearsing speech sounds, such as vowels and consonants
  • Using children’s books to practicing reading and writing
  • Reciting poems or nursery rhymes
  • Saying the names of famous sports personalities
  • Watching the news, and copying how the newsreader speaks
  • Persevering in conversation with friends or family, however difficult it is

It is important for friends and family to continue to treat the person as an intelligent adult, and to be aware that while their ability to communicate has changed, their identity has not. They are still who they are, with interests, skills, and a past.

In addition, everyone is different, and the effects of stroke vary. For this reason, there will not be a “one-size-fits-all” solution.

Full recovery is not always possible, but patience, help, support, and practice can go a long way in helping people to regain their communication skills after a stroke.

Source: Life after stroke: Tips for recovering communication skills – Medical News Today

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[WEB SITE] Brain plasticity after injury: an interview with Dr Swathi Kiran

What is brain plasticity and why is it important following a brain injury?

Brain plasticity is the phenomenon by which the brain can rewire and reorganize itself in response to changing stimulus input. Brain plasticity is at play when one is learning new information (at school) or learning a new language and occurs throughout one’s life.

Brain plasticity is particularly important after a brain injury, as the neurons in the brain are damaged after a brain injury, and depending on the type of brain injury, plasticity may either include repair of damaged brain regions or reorganization/rewiring of different parts of the brain.

MRI brain injury

How much is known about the level of injury the brain can recover from? Over what time period does the brain adapt to an injury?

A lot is known about brain plasticity immediately after an injury. Like any other injury to the body, after an initial negative reaction to the injury, the brain goes through a massive healing process, where the brain tries to repair itself after the injury. Research tells us exactly what kinds of repair processes occur hours, days and weeks after the injury.

What is not well understood is how recovery continues to occur in the long term. So, there is a lot research showing that the brain is plastic, and undergoes recovery even months after the brain damage, but what promotes such recovery and what hinders such recovery is not well understood.

It is well understood that some rehabilitative training promotes brain injury and most of the current research is focused on this topic.

What techniques are used to study brain plasticity?

Human brain plasticity has mostly been studied using non-invasive imaging methods, because these techniques allow us to measure the gray matter (neurons), white matter (axons) at a somewhat coarse level. MRI and fMRI techniques provide snapshots and video of the brain in function, and that allows us to capture changes in the brain that are interpreted as plasticity.

Also, more recently, there are invasive stimulation methods such as transcranial direct current stimulation or transcranial magnetic stimulation which allow providing electric current or magnetic current to different parts of the brain and such stimulation causes certain changes in the brain.

How has our understanding advanced over recent years?

One of the biggest shifts in our understanding of brain plasticity is that it is a lifelong phenomenon. We used to previously think that the brain is plastic only during childhood and once you reach adulthood, the brain is hardwired, and no new changes can be made to it.

However, we now know that even the adult brain can be modified and reorganized depending on what new information it is learning. This understanding has a profound impact on recovery from brain injury because it means that with repeated training/instruction, even the damaged brain is plastic and can recover.

What role do you see personalized medicine playing in brain therapy in the future?

One reason why rehabilitation after brain injury is so complex is because no two individuals are alike. Each individual’s education and life experiences have shaped their brain (due to plasticity!) in unique ways, so after a brain injury, we cannot expect that recovery in two individuals will be occur the same way.

Personalized medicine allows the ability to tailor treatment for each individual taking into account their strengths and weaknesses and providing exactly the right kind of therapy for that person. Therefore, one size treatment does not fit all, and individualized treatments prescribed to the exact amount of dosage will become a reality.

Senior couple tablet

What is ‘automedicine’ and do you think this could become a reality?

I am not sure we understand what automedicine can and cannot do just yet, so it’s a little early to comment on the reality. Using data to improve our algorithms to precisely deliver the right amount of rehabilitation/therapy will likely be a reality very soon, but it is not clear that it will eliminate the need for doctors or rehabilitation professionals.

What do you think the future holds for people recovering from strokes and brain injuries and what’s Constant Therapy’s vision?

The future for people recovering from strokes and brain injuries is more optimistic than it has ever been for three important reasons. First, as I pointed above, there is tremendous amount of research showing that the brain is plastic throughout life, and this plasticity can be harnessed after brain injury also.

Second, recent advances in technology allow patients to receive therapy at their homes at their convenience, empowering them to take control of their therapy instead of being passive consumers.

Finally, the data that is collected from individuals who continuously receive therapy provides a rich trove of information about how patients can improve after rehabilitation, what works and what does not work.

Constant Therapy’s vision incorporates all these points and its goal to provide effective, efficient and reasonable rehabilitation to patients recovering from strokes and brain injury.

Where can readers find more information?

About Dr Swathi Kiran

DR SWATHI KIRANSwathi Kiran is Professor in the Department of Speech and Hearing Sciences at Boston University and Assistant in Neurology/Neuroscience at Massachusetts General Hospital. Prior to Boston University, she was at University of Texas at Austin. She received her Ph.D from Northwestern University.

Her research interests focus around lexical semantic treatment for individuals with aphasia, bilingual aphasia and neuroimaging of brain plasticity following a stroke.

She has over 70 publications and her work has appeared in high impact journals across a variety of disciplines including cognitive neuroscience, neuroimaging, rehabilitation, speech language pathology and bilingualism.

She is a fellow of the American Speech Language and Hearing Association and serves on various journal editorial boards and grant review panels including at National Institutes of Health.

Her work has been continually funded by the National Institutes of Health/NIDCD and American Speech Language Hearing Foundation awards including the New Investigator grant, the New Century Scholar’s Grant and the Clinical Research grant. She is the co-founder and scientific advisor for Constant Therapy, a software platform for rehabilitation tools after brain injury.

Source: Brain plasticity after injury: an interview with Dr Swathi Kiran

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[WEB SITE] What Is Brain Plasticity and Why Is It So Important?

The malleable brain. http://www.shutterstock.com

Neuroplasticity – or brain plasticity – is the ability of the brain to modify its connections or re-wire itself. Without this ability, any brain, not just the human brain, would be unable to develop from infancy through to adulthood or recover from brain injury.

What makes the brain special is that, unlike a computer, it processes sensory and motor signals in parallel. It has many neural pathways that can replicate another’s function so that small errors in development or temporary loss of function through damage can be easily corrected by rerouting signals along a different pathway.

The problem becomes severe when errors in development are large, such as the effects of the Zika virus on brain development in the womb, or as a result of damage from a blow to the head or following a stroke. Yet, even in these examples, given the right conditions the brain can overcome adversity so that some function is recovered.

The brain’s anatomy ensures that certain areas of the brain have certain functions. This is something that is predetermined by your genes. For example, there is an area of the brain that is devoted to movement of the right arm. Damage to this part of the brain will impair movement of the right arm. But since a different part of the brain processes sensation from the arm, you can feel the arm but can’t move it. This “modular” arrangement means that a region of the brain unrelated to sensation or motor function is not able to take on a new role. In other words, neuroplasticity is not synonymous with the brain being infinitely malleable.

Free chapter: Neuroplasticity Associated with Treated Aphasia Recovery

Part of the body’s ability to recover following damage to the brain can be explained by the damaged area of the brain getting better, but most is the result of neuroplasticity – forming new neural connections. In a study ofCaenorhabditis elegans, a type of nematode used as a model organism in research, it was found that losing the sense of touch enhanced the sense of smell. This suggests that losing one sense rewires others. It is well known that, in humans, losing one’s sight early in life can heighten other senses, especially hearing.

As in the developing infant, the key to developing new connections is environmental enrichment that relies on sensory (visual, auditory, tactile, smell) and motor stimuli. The more sensory and motor stimulation a person receives, the more likely they will be to recover from brain trauma. For example, some of the types of sensory stimulation used to treat stroke patients includes training in virtual environments, music therapy and mentally practising physical movements.

The basic structure of the brain is established before birth by your genes. But its continued development relies heavily on a process called developmental plasticity, where developmental processes change neurons and synaptic connections. In the immature brain this includes making or losing synapses, the migration of neurons through the developing brain or by the rerouting and sprouting of neurons.

There are very few places in the mature brain where new neurons are formed. The exceptions are the dentate gyrus of the hippocampus (an area involved in memory and emotions) and the sub-ventricular zone of the lateral ventricle, where new neurons are generated and then migrate through to the olfactory bulb (an area involved in processing the sense of smell). Although the formation of new neurons in this way is not considered to be an example of neuroplasticity it might contribute to the way the brain recovers from damage. …

Visit Web Site —> What Is Brain Plasticity and Why Is It So Important? | SciTech Connect

 

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[ARTICLE] The complexity of the relationship between neuropsychological deficits and impairment in everyday tasks after stroke – Full Text HTML

Abstract

Background and purpose: A large body of research reports that stroke patients are debilitated in terms of daily independence after dismissal from the hospital unit. Patients struggle with the use of daily objects or performing complex actions. Differences between individual deficits of patients are often associated with the site of the brain damage. However, clinical studies suggest that patients exhibit varied constellations of action-associated difficulties and neuropsychological deficits. There is a lack of conclusive evidence indicating how different neuropsychological symptoms link to the impaired ability to perform activities of daily living (ADL).

Materials and methods: To further address this matter, in this study we compared the behavior of patients with left brain damage (LBD) and right brain damage (RBD) following stroke in two naturalistic task scenarios (tea making and document filing), and compared the committed action errors to the neuropsychological screening results.

Results: We observed mild to severe impairments in both the LBD and RBD groups amounting to 37–55% of failure rate in attainment of action goal. Interestingly, the performance on both tasks was not correlated to each other, suggesting that the tasks involved a different set of higher cognitive functions. Despite similar behavioral manifestations, in the LBD group poor task performance was related to deficits in praxis performance and unilateral tactile and visual extinction. The presence of aphasia did not correlate with task performance, except for a link between low scores in Aachen aphasia test scales and misestimation error in the tea making task. In the RBD group, difficulties with performance were primarily linked to deficit in praxis and unilateral visual extinction.

Conclusions: Despite similar behavior, the underlying mechanisms of the deficits after stroke might be different (in patients with LBD and RBD) and reveal complex interlinks of cognitive networks involved in the ability to carry on everyday tasks.

Full Text HTML —>  The complexity of the relationship between neuropsychological deficits and impairment in everyday tasks after stroke – Bieńkiewicz – 2015 – Brain and Behavior – Wiley Online Library

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