Transcranial direct current stimulation inhibits epileptic activity propagation in a large-scale brain network model

 With your chance of seizures and epilepsy post stroke, is your doctor prepared with this intervention?

Do you prefer your  doctor and hospital incompetence NOT KNOWING? OR NOT DOING?

 

• 10% seizures post stroke (19 posts to April 2017)

• 5% epileptic seizures after stroke (10 posts to April 2021)

• epileptic seizures (6 posts to December 2015)

• post-stroke epilepsy (7 posts to December 2016)

Transcranial direct current stimulation inhibits epileptic activity propagation in a large-scale brain network model

• Ying Yu,
• YuBo Fan,
• Fang Han,
• GuoMing Luan &
• QingYun Wang 

Science China Technological Sciences (2023)Cite this article

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Abstract

Transcranial direct current stimulation (tDCS) is a noninvasive technique that uses constant, low-intensity direct current to regulate brain activities. Clinical studies have shown that cathode-tDCS (c-tDCS) is effective in reducing seizure frequency in patients with epilepsy. Due to the heterogeneity and patient specificity of seizures, patient-specific epilepsy networks are increasingly important in exploring the regulatory role of c-tDCS. In this study, we first set the left hippocampus, para-hippocampus, and amygdala as the epileptogenic zone (EZ), and the left inferior temporal cortex and ventral temporal cortex as the initial propagation zone (PZ) to establish a large-scale epilepsy network model. Then we set tDCS cathode locations according to the maximum average energy of the simulated EEG signals and systematically study c-tDCS inhibitory effects on the propagation of epileptic activity. The results show that c-tDCS is effective in suppressing the propagation of epileptic activity. Further, to consider the patient specificity, we set specific EZ and PZ according to the clinical diagnosis of 6 patients and establish patient-specific epileptic networks. We find that c-tDCS can suppress the propagation of abnormal activity in most patient-specific epileptic networks. However, when the PZ is widely distributed in both hemispheres, the treatment effect of c-tDCS is not satisfactory. Hence, we propose dual-cathode tDCS. For epilepsy models with a wide distribution of PZ, it can inhibit the propagation of epileptiform activity in other nodes except EZ and PZ without increasing the tDCS current strength. Our results provide theoretical support for the treatment of epilepsy with tDCS.

Low-Frequency Repetitive Transcranial Magnetic Stimulation Over Contralesional Motor Cortex for Motor Recovery in Subacute Ischemic Stroke: A Randomized Sham-Controlled Trial

 Contralesional:Adjective. (not comparable) (medicine) Describing the half of a patient's brain or body away from the site of a lesion.

Or is c-tDCS (2 posts) better for contralesional stimulation?

Low-Frequency Repetitive Transcranial Magnetic Stimulation Over Contralesional Motor Cortex for Motor Recovery in Subacute Ischemic Stroke: A Randomized Sham-Controlled Trial

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Won-Seok Kim, MD, PhD, Bum Sun Kwon, MD, PhD, Han Gil Seo, MD, PhD, ...

First Published August 18, 2020 Research Article Find in PubMed 

https://doi.org/10.1177/1545968320948610

Article information

 

Abstract

Background

Low-frequency repetitive transcranial magnetic stimulation (rTMS) over the contralesional motor cortex (M1) has demonstrated beneficial effects on motor recovery, but evidence among patients with subacute stroke is lacking. We aimed to investigate whether 1-Hz rTMS over the contralesional M1 versus sham rTMS could improve arm function in patients with subacute ischemic stroke when combined with rehabilitative motor training.

Methods

In total, 77 patients who were within 90 days after their first-ever ischemic stroke were enrolled and randomly allocated to either real (n = 40) or sham rTMS (n = 37). We delivered 1-Hz 30-minute active or sham rTMS before each daily 30-minute occupational therapy sessions over a 2-week period. The primary endpoint was changes in the Box and Block Test (BBT) score immediately after the end of treatment (EOT). Secondary analyses assessed changes in Fugl-Meyer assessment, Finger Tapping Test (FTT), Brunnstrom stage, and grip strength.

Clinical Trial Registration

ClinialTrials.gov (NCT02082015).

Results

Changes in BBT immediately after the end of treatment did not differ significantly between the 2 groups (P = .267). Subgroup analysis according to cortical involvement revealed that real rTMS resulted in improvements in BBT at 1 month after EOT (17.4 ± 9.8 real vs 10.9 ± 10.3 sham; P = .023) and Brunnstrom stage of the hand immediately after EOT (0.6 ± 0.5 real vs 0.2 ± 0.5 sham; P = .023), only in the group without cortical involvement.

Conclusion

The effects of real and sham rTMS did not differ significantly among patients within 3 months poststroke. The location of stroke lesions should be considered for future clinical trials.

Keywords stroke, transcranial magnetic stimulation, rehabilitation, motor cortex, recovery of function, neuronal plasticity

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Contralesional Hemisphere Control of the Proximal Paretic Upper Limb following Stroke

'Can' and 'may' are not good enough. There is nothing here that I can take to any doctor and therapists to get any survivor recovered. Useless. 

Contralesional Hemisphere Control of the Proximal Paretic Upper Limb following Stroke

Lynley V. Bradnam1,2, Cathy M. Stinear2,3, P. Alan Barber2,3 and Winston D. Byblow 1,21Movement Neuroscience Laboratory, Department of Sport & Exercise Science, and 2Centre for Brain Research and Neurology Research Group, Department of Medicine, The University of Auckland, Auckland, New Zealand 1142. Address correspondence to Winston D. Byblow, Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of  Auckland, Auckland, New Zealand 1142. Email: w.byblow@auckland.ac.nz.

Cathodal transcranial direct current stimulation (c-tDCS) can reduce excitability of neurons in primary motor cortex (M1) and may facilitate motor recovery after stroke. However, little is known about the neurophysiological effects of tDCS on proximal upper limb function. We hypothesized that suppression of contralesional M1 (cM1) excitability would produce neurophysiological effects that depended on the severity of upper limb impairment. Twelve patients with varying upper limb impairment after subcortical stroke were assessed on clinical scales of upper limb spasticity, impairment, and function. Magnetic resonance imaging was used to determine lesion size and  (FA) within the posterior limbs of the internal capsules indicative of corticospinal tract integrity. Excitability within paretic M1 biceps brachii representation was determined from motor-evoked potentials during selective isometric tasks, after cM1 sham stimulation and after c-tDCS. These neurophysiological data indicate that c-tDCS improved selective proximal upper limb control for mildly impaired patients and worsened it for moderate to severely impaired patients. The direction of the neurophysiological after effects of c-tDCS was strongly related to upper limb spasticity, impairment,function, and FA asymmetry between the posterior limbs of the internal capsules. These results indicate systematic variation of cM1 for proximal upper limb control after stroke and that suppression of cM1 excitability is not a ‘‘one size fits all’’ approach.(But you don't tell us EXACTLY which patients it does fit. What damage diagnosis would this work for? Useless. )

Contralesional Hemisphere Control of the Proximal Paretic Upper Limb following Stroke

'May' and 'can' is not good enough. We need stroke protocols leading to 100% recovery.  This is extreme laziness. The whole point of stroke research is protocols leading to recovery. NOTHING LESS!  Talk to survivors sometime and see what they want without your assumption of tyranny of low expectations.

 

Contralesional Hemisphere Control of the Proximal Paretic Upper Limb following Stroke

Lynley V. Bradnam1,2, Cathy M. Stinear2,3, P. Alan Barber2,3 and Winston D. Byblow1,2 1Movement Neuroscience Laboratory, Department of Sport & Exercise Science, and 2Centre for Brain Research and 3Neurology Research Group, Department of Medicine, The University of Auckland, Auckland, New Zealand 1142.
Address correspondence to Winston D. Byblow, Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of Auckland, Auckland, New Zealand 1142. Email: w.byblow@auckland.ac.nz.
Cathodal transcranial direct current stimulation (c-tDCS) can reduce excitability of neurons in primary motor cortex (M1) and may facilitate motor recovery after stroke. However, little is known about the neurophysiological effects of tDCS on proximal upper limb function. We hypothesized that suppression of contralesional M1 (cM1) excitability would produce neurophysiological effects that depended on the severity of upper limb impairment. Twelve patients with varying upper limb impairment after subcortical stroke were assessed on clinical scales of upper limb spasticity, impairment, and function. Magnetic resonance imaging was used to determine lesion size and fractional anisotropy (FA) within the posterior limbs of the internal capsules indicative of corticospinal tract integrity. Excitability within paretic M1 biceps brachii representation was determined from motor-evoked potentials during selective isometric tasks, after cM1 sham stimulation and after c-tDCS. These neurophysiological data indicate that c-tDCS improved selective proximal upper limb control for mildly impaired patients and worsened it for moderate to severely impaired patients. The direction of the neurophysiological after effects of c-tDCS was strongly related to upper limb spasticity, impairment, function, and FA asymmetry between the posterior limbs of the internal capsules. These results indicate systematic variation of cM1 for proximal upper limb control after stroke and that suppression of cM1 excitability is not a ‘‘one size fits all’’ approach.