Posts Tagged Transcranial Direct Current Stimulation

[Abstract] Functional Brain Stimulation in a Chronic Stroke Survivor With Moderate Impairment  

Abstract

OBJECTIVE. To determine the impact of transcranial direct current stimulation (tDCS) combined with repetitive, task-specific training (RTP) on upper-extremity (UE) impairment in a chronic stroke survivor with moderate impairment.

METHOD. The participant was a 54-yr-old woman with chronic, moderate UE hemiparesis after a single stroke that had occurred 10 yr before study enrollment. She participated in 45-min RTP sessions 3 days/wk for 8 wk. tDCS was administered concurrent to the first 20 min of each RTP session.

RESULTS. Immediately after intervention, the participant demonstrated marked score increases on the UE section of the Fugl–Meyer Scale and the Motor Activity Log (on both the Amount of Use and the Quality of Movement subscales).

CONCLUSION. These data support the use of tDCS combined with RTP to decrease impairment and increase UE use in chronic stroke patients with moderate impairment. This finding is crucial, given the paucity of efficacious treatment approaches in this impairment level.

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Source: Functional Brain Stimulation in a Chronic Stroke Survivor With Moderate Impairment | American Journal of Occupational Therapy

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[Abstract] Spasticity Management: The Current State of Transcranial Neuromodulation

Abstract

This narrative review aims to provide an objective view of the non-invasive neuromodulation (NINM) protocols available for treating spasticity, including repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). On the basis of the relevant randomized controlled trials, we infer that NINM is more effective in reducing spasticity when combined with the conventional therapies than used as a stand-alone treatment. However, the magnitude of NINM aftereffects depends significantly on the applied hemisphere and the underlying pathology. Being in line with these arguments, low-frequency rTMS and cathodal-tDCS over the unaffected hemisphere are more effective in reducing spasticity than high-frequency rTMS and anodal-tDCS over the affected hemisphere in chronic post-stroke. However, most of the studies are heterogeneous in the stimulation setup, patient selection, follow-up duration, and the availability of the sham operation. Therefore, the available data on the usefulness of NINM in reducing spasticity need to be confirmed by further larger and multicentric randomized controlled trials to gather evidence on the efficiency of NINM regimens in reducing spasticity in various neurologic conditions.

Source: Spasticity Management: The Current State of Transcranial Neuromodulation

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[ARTICLE] The impact of large structural brain changes in chronic stroke patients on the electric field caused by transcranial brain stimulation – Full Text

Abstract

Transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (TDCS) are two types of non-invasive transcranial brain stimulation (TBS). They are useful tools for stroke research and may be potential adjunct therapies for functional recovery. However, stroke often causes large cerebral lesions, which are commonly accompanied by a secondary enlargement of the ventricles and atrophy. These structural alterations substantially change the conductivity distribution inside the head, which may have potentially important consequences for both brain stimulation methods. We therefore aimed to characterize the impact of these changes on the spatial distribution of the electric field generated by both TBS methods. In addition to confirming the safety of TBS in the presence of large stroke-related structural changes, our aim was to clarify whether targeted stimulation is still possible. Realistic head models containing large cortical and subcortical stroke lesions in the right parietal cortex were created using MR images of two patients. For TMS, the electric field of a double coil was simulated using the finite-element method. Systematic variations of the coil position relative to the lesion were tested. For TDCS, the finite-element method was used to simulate a standard approach with two electrode pads, and the position of one electrode was systematically varied. For both TMS and TDCS, the lesion caused electric field “hot spots” in the cortex. However, these maxima were not substantially stronger than those seen in a healthy control. The electric field pattern induced by TMS was not substantially changed by the lesions. However, the average field strength generated by TDCS was substantially decreased. This effect occurred for both head models and even when both electrodes were distant to the lesion, caused by increased current shunting through the lesion and enlarged ventricles. Judging from the similar peak field strengths compared to the healthy control, both TBS methods are safe in patients with large brain lesions (in practice, however, additional factors such as potentially lowered thresholds for seizure-induction have to be considered). Focused stimulation by TMS seems to be possible, but standard tDCS protocols appear to be less efficient than they are in healthy subjects, strongly suggesting that tDCS studies in this population might benefit from individualized treatment planning based on realistic field calculations.

1. Introduction

Transcranial brain stimulation (TBS) methods are useful tools to induce and to quantify neural plasticity, and as such are increasingly being used in stroke research and as potential adjunct therapies in stroke rehabilitation. The cerebral lesions caused by stroke result in persisting physical or cognitive impairments in around 50% of all survivors (Di Carlo, 2008Leys et al., 2005 ;  Young and Forster, 2007), meaning that new therapies are urgently needed. Transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (TDCS) are two TBS approaches which are being increasingly utilised in stroke research. Single-pulse TMS combined with electromyography (EMG) or electroencephalography (EEG) can be used to assess cortical excitability, for example to index the functional state of the perilesional tissue. The neuromodulatory effects of repetitive TMS protocols (rTMS) may, in association with neuro-rehabilitative treatments, enhance motor recovery (Liew et al., 2014). Similar results have been demonstrated for TDCS. For example, anodal TDCS of the hand area in the primary motor cortex has been shown to improve motor performance of the affected hand (Allman et al., 2016Hummel et al., 2005 ;  Stagg et al., 2012) and anodal TDCS applied over the left frontal cortex enhanced naming accuracy in patients with aphasia (Baker et al., 2010). However, not all studies report a clear-cut positive impact of TBS on the stroke symptoms. Rather, the observed effects are often weak and not consistent across patients, demonstrating the need for a better understanding of the underlying biophysical and physiological mechanisms.

Compared with healthy subjects, several factors might contribute to a change in the neuroplastic response to TBS protocols in stroke patients, including changes in the neural responsiveness to the applied electric fields, as well as differences in the underlying physiology and metabolism (Blicher et al., 2009Blicher et al., 2015 ;  O’Shea et al., 2014). When the lesions are large, they may also substantially alter the generated electric field pattern, meaning that the assumptions on spatial targeting as derived from biophysical modelling and physiological experiments in healthy subjects might no longer be valid. Stroke lesions are often accompanied by secondary macrostructural changes such as cortical atrophy and enlargement of the ventricles (e.g., Skriver et al., 1990), which may further contribute to changes in the field pattern. In addition, the safety of TBS in patients with large lesions needs to be further clarified, as it is possible that the lesions might cause stimulation “hot spots”. In chronic patients, the stroke cavity becomes filled with corticospinal fluid (CSF), which might cause shunting of current, funnelling the generated currents towards the surrounding brain tissue and potentially causing localized areas of dangerously high field strengths.

Here, using finite-element calculations and individual head models derived from structural MR images, we focused on the impact of a large cortical lesion in chronic stroke on the electric field pattern generated in the brain by TMS and TDCS, respectively. Firstly, we assessed the safety of the stimulation by comparing the achieved field strengths with those estimated for a healthy control. Secondly, we tested how reliably we can accurately target the perilesional tissue, often the desired target for TBS, as reorganisation here is thought to underpin functional recovery (Kwakkel et al., 2004). Finally, we were also interested to see whether any observed changes in the field pattern were specific to a patient with a cortical lesion (which is connected to the CSF layer underneath the skull), or whether similar effects might occur in case of large chronic subcortical lesion. We therefore additionally tested the field distribution in a head model of a patient with a subcortical lesion occurring at a similar position as the cortical lesion.

2. Materials and methods

2.1. Selection of patients

The aim of this study was to characterize the effect of a large chronic cortical stroke lesion on the electric field distribution generated by TBS, and to compare the effects of this lesion to that caused by a large chronic subcortical lesion. MR images of several patients were visually inspected to select two datasets, which had a cortical [P01] and subcortical lesion [P02], respectively, within the same gross anatomical regions.

Patient P01 was a 36 year old female with episodic migraine; she was admitted with left hemiparalysis, fascial palsy and a total NIHSS score of 16 due to a right ICI/MCI occlusion. She was treated with IV thrombolysis and thrombectomy and recanalization was achieved 5 h after symptom onset. One year post-stroke she still suffered from motor impairment (Wolf Motor Function Test [WMFT] score of 30) and was scanned as part of a clinical study investigating the effect of combining Constraint-Induced Movement Therapy and tDCS (Figlewski et al., 2017; Clinical trials NCT01983319, Regional Ethics approval: 1-10-72-268-13). The structural scans showed a cortical lesion in the right parietal lobe (Fig. 1A). The lesion volume, delineated manually with reference to T1- and T2-weighted imaging, was 26,415 mm3.

Fig. 1:Fig. 1.

A) Coronal view of patient P01 with a cortical lesion in the right hemisphere. The top shows the T1-weighted MR image and the bottom the reconstructed head mesh. The view was chosen to include the lesion centre. The lesion is marked by red dashed circles. B) Corresponding view of patient P02 with a large subcortical lesion at a similar location in the right hemisphere. C) Corresponding view of the data set of the healthy control. D) The coil and electrode positions were systematically moved along two directions that were approximately perpendicular to each other. Five positions were manually placed every 2 cm in posterior – anterior direction symmetrically around the centre of the cortical lesion. The same was repeated along the lateral – medial direction. Both lines share the same centre position above the lesion, resulting in 9 positions in total. E) At each position, two coil orientations were tested which resulted in a current flow underneath the coil centre from anterior to posterior (top) and from lateral to medial, respectively (bottom). F) For each position of the yellow “stimulating” electrode, two positions of the blue return electrode were tested. First, the contralateral equivalent of the electrode position above the centre of the cortical lesion was used (top). In addition, a position on the contralateral forehead was tested (bottom).

Patient P02 was a 44 year old female. She woke up with a left hemiparesis and an acute CT scan showed no bleeding. No IV thrombolysis was given due to uncertain timing of symptom onset. An embolic stroke was suspect due to a patent foramen ovale, which was subsequently closed. She was scanned with MRI 9 months post stroke showing a right subcortical infarct, at which time she had a WMFT score of 8. The lesion volume, delineated as for P01, was 56,010 mm3. She was scanned as part of a clinical study investigating the effect of combining tDCS with daily motor training (Allman et al., 2016; Regional Ethics approval: Oxfordshire REC A; 10/H0604/98)….

Continue —> The impact of large structural brain changes in chronic stroke patients on the electric field caused by transcranial brain stimulation

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[ARTICLE] Transcranial Direct Current Stimulation Does Not Affect Lower Extremity Muscle Strength Training in Healthy Individuals: A Triple-Blind, Sham-Controlled Study – Full Text

The present study investigated the effects of anodal transcranial direct current stimulation (tDCS) on lower extremity muscle strength training in 24 healthy participants. In this triple-blind, sham-controlled study, participants were randomly allocated to the anodal tDCS plus muscle strength training (anodal tDCS) group or sham tDCS plus muscle strength training (sham tDCS) group. Anodal tDCS (2 mA) was applied to the primary motor cortex of the lower extremity during muscle strength training of the knee extensors and flexors. Training was conducted once every 3 days for 3 weeks (7 sessions). Knee extensor and flexor peak torques were evaluated before and after the 3 weeks of training. After the 3-week intervention, peak torques of knee extension and flexion changed from 155.9 to 191.1 Nm and from 81.5 to 93.1 Nm in the anodal tDCS group. Peak torques changed from 164.1 to 194.8 Nm on extension and from 78.0 to 85.6 Nm on flexion in the sham tDCS group. In both groups, peak torques of knee extension and flexion significantly increased after the intervention, with no significant difference between the anodal tDCS and sham tDCS groups. In conclusion, although the administration of eccentric training increased knee extensor and flexor peak torques, anodal tDCS did not enhance the effects of lower extremity muscle strength training in healthy individuals. The present null results have crucial implications for selecting optimal stimulation parameters for clinical trials.

Introduction

Transcranial direct current stimulation (tDCS) is a non-invasive cortical stimulation procedure in which weak direct currents polarize target brain regions (Nitsche and Paulus, 2000). The application of anodal tDCS to the primary motor cortex of the lower extremity transiently increases corticospinal excitability in healthy individuals (Jeffery et al., 2007Tatemoto et al., 2013) and improves motor function in healthy individuals and patients with stroke (Tanaka et al., 20092011Madhavan et al., 2011Sriraman et al., 2014Chang et al., 2015Montenegro et al., 20152016Angius et al., 2016Washabaugh et al., 2016). Thus, anodal tDCS has a potential to become a new adjunct therapeutic strategy for the rehabilitation of leg motor function and locomotion following a stroke.

Lower leg muscle strength is an important motor function required for patients who have had a stroke to regain activities of daily living (ADL). Lower leg muscle strength correlates with performance in activities, including sit-to-stand, gait, and stair ascent (Bohannon, 2007). Furthermore, lower leg muscle strength training increases muscle strength and improves ADL in patients with stroke (Ada et al., 2006). Therefore, lower leg muscle strength training is one of the important activities rehabilitating patients with stroke to regain their independence in ADL.

Several studies have examined the effect of a single session of tDCS on lower leg muscle strength, although the evidence is inconsistent (Tanaka et al., 20092011Montenegro et al., 20152016Angius et al., 2016Washabaugh et al., 2016). Its effects seem dependent on tDCS protocols, training tasks, muscle groups, and subject populations. Although, most tDCS studies on lower leg muscle strength have focused on the acute effects of a single tDCS application, to the best of our knowledge, no study has examined how lower extremity strength training combined with repeated sessions of tDCS affects lower leg muscle strength. This type of investigation has strong clinical implications for the application of tDCS in rehabilitation for patients with lower leg muscle weakness.

Thus, to examine whether anodal tDCS can enhance the effects of lower extremity muscle strength training, the present study simultaneously applied anodal tDCS and lower extremity muscle strength training to healthy individuals and evaluated their effects on lower extremity muscle strength.

Continue —> Frontiers | Transcranial Direct Current Stimulation Does Not Affect Lower Extremity Muscle Strength Training in Healthy Individuals: A Triple-Blind, Sham-Controlled Study | Perception Science

Figure 1. Experimental setup of the muscle strength training and torque assessment.

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[ARTICLE] Notes on Human Trials of Transcranial Direct Current Stimulation between 1960 and 1998 – Full Text

Background: Transcranial direct current stimulation (tDCS) is investigated to modulate neuronal function including cognitive neuroscience and neuropsychiatric therapies. While cases of human stimulation with rudimentary batteries date back more than 200 years, clinical trials with current controlled stimulation were published intermittently since the 1960s. The modern era of tDCS only started after 1998.

Objectives: To review methods and outcomes of tDCS studies from old literature (between 1960 and 1998) with intention of providing new insight for ongoing tDCS trials and development of tDCS protocols especially for the purpose of treatment.

Methods: Articles were identified through a search in PubMed and through the reference list from its selected articles. We included only non-invasive human studies that provided controlled direct current and were written in English, French, Spanish or Portuguese before the year of 1998, the date in which modern stimulation paradigms were implemented.

Results: Fifteen articles met our criteria. The majority were small-randomized controlled clinical trials that enrolled a mean of approximately 26 subjects (Phase II studies). Most of the studies (around 83%) assessed the role of tDCS in the treatment of psychiatric conditions, in which the main outcomes were measured by means of behavioral scales and clinical observation, but the diagnostic precision and the quality of outcome monitoring, including adverse events, were deficient by modern standards. Compared to modern tDCS dose, the stimulation intensities used (0.1–1 mA) were lower, however as the electrodes were typically smaller (e.g., 1.26 cm2), the average electrode current density (0.2 mA/cm2) was approximately 4× higher. The number of sessions ranged from one to 120 (median 14). Notably, the stimulation session durations of several minutes to 11 h (median 4.5 h) could markedly exceed modern tDCS protocols. Twelve studies out of 15 showed positive results. Only mild side effects were reported, with headache and skin alterations the most common.

Conclusion: Most of the studies identified were for psychiatric indications, especially in patients with depression and/or schizophrenia and majority indicated some positive results. Variability in outcome is noted across trials and within trials across subjects, but overall results were reported as encouraging, and consistent with modern efforts, given some responders and mild side effects. The significant difference with modern dose, low current with smaller electrode size and interestingly much longer stimulation duration may worth considering.

Introduction

Transcranial direct current stimulation (tDCS) consists of applying a weak direct current on the scalp, a portion of which crosses the skull (Datta et al., 2009) and induces cortical changes (Fregni and Pascual-Leone, 2007; Nitsche et al., 2008). The investigation of the application of electricity over the brain dates back to at least 200 years, when Giovanni Aldini (Zaghi et al., 2010) recommended galvanism for patients with deafness, amaurosis and “insanity”, reporting good results with this technique especially when used in patients with “melancholia”. Aldini also used tDCS in patients with symptoms of personality disorders and supposedly reported complete rehabilitation following transcranial administration of electric current (Parent, 2004).

These earliest studies used rudimentary batteries and so were constant voltage, where the resulting current depends on a variable body resistance. Over the 20th century, direct voltage continued to be used but most testing involved pulsed stimulation, starting with basic devices where a mechanical circuit that intermittently connected and broke the circuit between the battery and the subject and evolving to modern current control circuits including Cranial Electrotherapy Stimulation and its variants (Guleyupoglu et al., 2013). Interest in direct current stimulation (or tDCS) resurged with the studies of Priori et al. (1998) and Nitsche and Paulus (2000) that demonstrated weak direct current could change cortical response to Transcranial Magnetic Stimulation, thereby indicating that tDCS could change cortical “excitability”. Testing for clinical and cognitive modification soon followed (Fregni et al., 2005, 2006). Developments and challenges in tDCS research, including applications in the treatment of neuro-psychiatrics disease since 1998 have been reviewed in detailed elsewhere (Brunoni et al., 2012).

This historical note aims to explore earlier data on human trial using current controlled stimulation (tDCS) before 1998 with the goal of informing ongoing understanding and development of tDCS protocols. As expected, we found variability in the quality of trial design, data collection and reporting in these earlier studies. Nonetheless, many clinical findings are broadly consistent with modern efforts, including some encouraging results but also variability across subjects. We also describe a significant difference in dose with lower current, smaller electrodes and much longer durations (up to 11 h) than used in modern tDCS.

Figure 2. Summary of study parameters on human trials using transcranial direct current stimulation (tDCS) in old literature (from 1960 to 1998). Models of commonly used montages of tDCS in early studies (A); red: anode electrode(s), blue: cathode electrode(s). Total number of subjects in each group of patients participating in studies using aforementioned montages (B.1) and leading countries conducting tDCS studies in early stage with number of published articles (B.2).

Continue —> Frontiers | Notes on Human Trials of Transcranial Direct Current Stimulation between 1960 and 1998 | Frontiers in Human Neuroscience

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[Abstract] The effect of transcranial direct current stimulation on motor sequence learning and upper limb function after stroke

Introduction

Transcranial direct current stimulation (tDCS) is a safe and non-invasive brain stimulation technique with the potential to improve upper limb function after stroke. Ipsilesional primary motor cortex (M1) excitability can be increased with anodal tDCS, contralesional M1 excitability can be decreased with cathodal tDCS or both anodal and cathodal tDCS can be used simultaneously on both cortices (bihemispheric). The impact of these different electrode arrangements on the efficacy of tDCS, and whether any of the changes are due to callosal connections between cortices, is unclear.

Objectives

This study aimed to investigate the effect of tDCS electrode arrangement on motor sequence learning and upper limb function in chronic stroke survivors.

Patients and methods

21 stroke survivors (range 3–124 months post-stroke, 34–81 years of age) with upper limb impairment received 20 min of 1 mA tDCS (0.04 mA·cm−2) during performance of a motor sequence learning task which involved movement of a computer mouse with the paretic arm to circular targets on a monitor in a repeating pattern. Four tDCS conditions were studied in a repeated-measures design; (i) anodal to the ipsilesional M1, (ii) cathodal to the contralesional M1, (iii) bihemispheric and (iv) sham. Upper limb function was assessed before and after tDCS, using the Jebsen–Taylor hand function test (JTT). Changes in transcallosal inhibition (TCI) were assessed using transcranial magnetic stimulation (ipsilateral silent period duration).

Results

There was no effect of tDCS condition on performance of the motor sequence learning task. Performance on the JTT improved significantly after unilateral tDCS (anodal or cathodal) compared to sham (p < 0.05), but not after bihemispheric (Fig. 1). There was no effect on TCI (p > 0.5), and no relationship between changes in TCI and upper limb function.

Conclusions

Unilateral, but not bihemispheric, tDCS improves upper limb function. The response to tDCS does not appear to be driven by changes in TCI. These results have implications for the use of tDCS for upper limb rehabilitation.

Source: P244 The effect of transcranial direct current stimulation on motor sequence learning and upper limb function after stroke – Clinical Neurophysiology

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[ARTICLE] Anatomical Parameters of tDCS to Modulate the Motor System after Stroke: A Review – Full Text

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation method to modulate the local field potential in neural tissue and consequently, cortical excitability. As tDCS is relatively portable, affordable, and accessible, the applications of tDCS to probe brain-behavior connections have rapidly increased in the last ten years. One of the most promising applications is the use of tDCS to modulate excitability in the motor cortex after stroke and promote motor recovery. However, the results of clinical studies implementing tDCS to modulate motor excitability have been highly variable, with some studies demonstrating that as many as 50% or more of patients fail to show a response to stimulation. Much effort has therefore been dedicated to understanding the sources of variability affecting tDCS efficacy. Possible suspects include the placement of the electrodes, task parameters during stimulation, dosing (current amplitude, duration of stimulation, frequency of stimulation), individual states (e.g., anxiety, motivation, attention), and more. In this review, we first briefly review potential sources of variability specific to stroke motor recovery following tDCS. We then examine how the anatomical variability in tDCS placement (e.g., neural target(s) and montages employed) may alter the neuromodulatory effects that tDCS exerts on the post-stroke motor system.

Introduction

Stroke is a neurological deficit induced by the interruption of the blood flow to the brain due to either a vessel occlusion or less frequently an intracerebral hemorrhage (1). Both may induce direct damage of brain tissue at the site of the lesion, along with potential for additional damage in the surrounding tissue, and long-range dysfunction through the interruption of structural and functional pathways in the brain. This also leads to a deregulation of cortical excitability (24) and abnormal interhemispheric interactions. Stroke may thus induce many neurological deficits and could result in death. According to the World Stroke Organization, one out of six people will suffer from a stroke, making stroke a leading cause of adult long-term disability worldwide (57). Importantly, one of the main challenges after stroke is the loss of one’s functional motor abilities. Research suggests that only 12% of stroke survivors achieve complete motor recovery by 6 months after the stroke (8). In addition, older individuals are more vulnerable to stroke and thus the incidence of stroke is expected to continue rising over the next few decades (9, 10). Accordingly, there is a need to find new potential therapeutic tools to enhance post-stroke motor recovery. Rebalancing interhemispheric interactions and/or restoring excitability in the ipsilesional hemisphere is thought to be beneficial for post-stroke motor recovery (1117). Thus, techniques aimed at restoring functional brain activity are a promising way to enhance neural recovery after injury. Most of the literature on stroke recovery focuses on the recovery of upper limb motor function. Since the neural mechanisms involved in motor recovery of upper versus lower limbs may differ, in this review, we focus only on upper limb motor recovery after stroke.

Non-invasive brain stimulation (NIBS) techniques show strong therapeutic potential for post-stroke motor rehabilitation due to their ability to modulate cortical excitability (1821). In particular, transcranial direct current stimulation (tDCS) has emerged as a viable neurorehabilitation tool due to its limited side-effects (22, 23) and safety [e.g., no known risk of neural damage or induction of seizures, as can be found in other NIBS methods like repetitive transcranial magnetic stimulation (rTMS) (24, 25)]. In addition, tDCS stimulators are commercially available and relatively affordable, on the order of several hundred dollars, and application of tDCS is considered relatively simple. By delivering a low-intensity direct current (between 0.5 and 2 mA) to the scalp via two saline-soaked electrodes—an anode and a cathode—tDCS can modulate the transmembrane potential of neurons, modifying cortical excitability and inducing changes in neural plasticity (see Figure 1) (2630). In addition, recent work has attempted to enhance the spatial resolution of tDCS stimulation, using a new technique called high-definition tDCS (HD-tDCS) (3134). With this technique, brain regions are more focally targeted using arrays of smaller electrodes arranged on the scalp (Figure 2), using multiple anodes and cathodes (see section on Focal versus Broad Stimulation for a more detailed description). Recently, there has also been increased interest in combining tDCS with imaging methods, such as fMRI or EEG, in order to better understand the local and global effects of tDCS on neural plasticity throughout the brain (35). These methods have all contributed to the growth and interest of tDCS as a viable neuromodulatory method for stroke.

Figure 1. Conventional transcranial direct current stimulation (tDCS) setup. The conventional tDCS setup requires a small tDCS stimulator with a 9-V battery, two saline-soaked sponge electrodes and one rubber band to hold the electrodes in place on the head. While there are many options for convention tDCS, the unit shown here is the Chattanooga Iontophoresis device.

Continue —> Frontiers | Anatomical Parameters of tDCS to Modulate the Motor System after Stroke: A Review | Movement Disorders

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[Abstract] Breakthroughs in the spasticity management: Are non-pharmacological treatments the future?

Highlights

  • Spasticity can cause a severe disability and challenge the rehabilitation process.
  • A successful treatment of spasticity depends on a pathophysiologic assessment.
  • The main therapeutic options include physiotherapy and pharmacological treatments.
  • Non-pharmacologic approaches may reduce spasticity and improve quality of life.

Abstract

The present paper aims at providing an objective narrative review of the existing non-pharmacological treatments for spasticity. Whereas pharmacologic and conventional physiotherapy approaches result well effective in managing spasticity due to stroke, multiple sclerosis, traumatic brain injury, cerebral palsy and incomplete spinal cord injury, the real usefulness of the non-pharmacological ones is still debated. We performed a narrative literature review of the contribution of non-pharmacological treatments to spasticity management, focusing on the role of non-invasive neurostimulation protocols (NINM). Spasticity therapeutic options available to the physicians include various pharmacological and non-pharmacological approaches (including NINM and vibration therapy), aimed at achieving functional goals for patients and their caregivers. A successful treatment of spasticity depends on a clear comprehension of the underlying pathophysiology, the natural history, and the impact on patient’s performances. Even though further studies aimed at validating non-pharmacological treatments for spasticity should be fostered, there is growing evidence supporting the usefulness of non-pharmacologic approaches in significantly helping conventional treatments (physiotherapy and drugs) to reduce spasticity and improving patient’s quality of life. Hence, non-pharmacological treatments should be considered as a crucial part of an effective management of spasticity.

Source: Breakthroughs in the spasticity management: Are non-pharmacological treatments the future? – Journal of Clinical Neuroscience

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[Abstract] Breakthroughs in the spasticity management: Are non-pharmacological treatments the future?

 

Highlights

    Spasticity can cause a severe disability and challenge the rehabilitation process.
    A successful treatment of spasticity depends on a pathophysiologic assessment.
    The main therapeutic options include physiotherapy and pharmacological treatments.
    Non-pharmacologic approaches may reduce spasticity and improve quality of life.

Abstract

The present paper aims at providing an objective narrative review of the existing non-pharmacological treatments for spasticity. Whereas pharmacologic and conventional physiotherapy approaches result well effective in managing spasticity due to stroke, multiple sclerosis, traumatic brain injury, cerebral palsy and incomplete spinal cord injury, the real usefulness of the non-pharmacological ones is still debated.

We performed a narrative literature review of the contribution of non-pharmacological treatments to spasticity management, focusing on the role of non-invasive neurostimulation protocols (NINM). Spasticity therapeutic options available to the physicians include various pharmacological and non-pharmacological approaches (including NINM and vibration therapy), aimed at achieving functional goals for patients and their caregivers. A successful treatment of spasticity depends on a clear comprehension of the underlying pathophysiology, the natural history, and the impact on patient’s performances.

Even though further studies aimed at validating non-pharmacological treatments for spasticity should be fostered, there is growing evidence supporting the usefulness of non-pharmacologic approaches in significantly helping conventional treatments (physiotherapy and drugs) to reduce spasticity and improving patient’s quality of life.

Hence, non-pharmacological treatments should be considered as a crucial part of an effective management of spasticity.

Source: Breakthroughs in the spasticity management: Are non-pharmacological treatments the future?

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[REVIEW] TRANSCRANIAL DIRECT CURRENT STIMULATION (tDCS) AND TRANSCRANIAL CURRENT ALTERNATING STIMULATION (tACS) REVIEW – Full Text PDF

Abstract

This literature review is aimed to explore the main technical characteristics of both transcranial direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS) using the latest research on both healthy and impaired subjects. These techniques have no official standards developed yet. Our intent is to underline the main properties and problems linked with the application of those techniques which show diverse, and sometimes even opposite, results depending mainly on electrode positioning and underlying brain activity.
1 INTRODUCTION
Among different impairments that can affect standard brain functions, we choose to focus primarily on stroke, because it is one of the most prevalent and severe disability worldwide [1]. It is known that after a cerebrovascular accident, reorganization of neural tissues takes place [18]. If the ischemic event occurs on the motor area and it is severe enough to block the spontaneous neural reorganization, it could lead to paresis or even paralysis of one or more body parts [24].
In order to ameliorate stroke rehabilitation, different approaches have been carried out. Over the last decade, within the field of functional rehabilitation, transcranial current stimulation (tCS) has garnered considerable attention. It is assumed to improve, above other, motor functions in both healthy and stroke individuals [25], [4], [23].
There are three different types of tCS: transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS) and random noise stimulation (tRNS). All of them are non-invasive and involve low intensity current induction into the brain. Some studies have investi
gated the physiological basis of tDCS and tACS in order to get the picture of standard pattern that can be used for future research [36], [32].
This paper is oriented towards a broad audience who wants to understand the basic mechanisms of tDCS and tACS techniques. The main parameters of each type of stimulation and the implications related to its application on healthy subjects, stroke patients and individuals with unusual brain oscillations are discussed.

Full Text PDF

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