Motor Learning in a Complex Motor Task Is Unaffected by Three Consecutive Days of Transcranial Alternating Current Stimulation

Bioengineering, Год журнала: 2024, Номер 11(8), С. 744 - 744

Опубликована: Июль 23, 2024

Transcranial alternating current stimulation (tACS) delivered to the primary motor cortex (M1) can increase cortical excitability, entrain neuronal firing patterns, and skill acquisition in simple tasks. The aim of this study was assess impact tACS applied M1 over three consecutive days practice on learning a challenging overhand throwing task young adults. secondary examine influence excitability. This implemented double-blind, randomized, SHAM-controlled, between-subjects experimental design. A total 24 healthy adults were divided into SHAM groups performed identical sessions that comprised blocks trials right dominant arm concurrent with application left M1. Performance quantified as endpoint error. Motor evoked potentials (MEPs) assessed first dorsal interosseus (FDI) muscle transcranial magnetic (TMS) quantify changes Endpoint error significantly decreased post-tests compared pre-tests when averaged (

Язык: Английский

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Cerebellar non-invasive stimulation of social and emotional mentalizing: A meta-analysis

Imaging Neuroscience, Год журнала: 2024, Номер 2, С. 1 - 25

Опубликована: Янв. 1, 2024

Abstract The present meta-analysis investigated the impact of non-invasive stimulation, using transcranial direct current stimulation (tDCS) and magnetic (TMS) targeting posterior cerebellum, on social emotional mentalizing about others. Prior research has convincingly shown that cerebellum supports cognition. We identified 14 studies with appropriate control conditions (i.e., sham, site), which exclude general learning effects task or placebo effects. included 29 where before during a was applied healthy samples. results showed significant evidence sustained anodal tDCS TMS generally improved performance after in comparison sham conditions, small effect size. In contrast, cathodal mixed facilitatory inhibitory results. addition, short pulses, administered aim interfering ongoing processes, induced but consistent effect. Control tasks without components also improvement TMS, suggesting may improve other functions. This not case for did modulate non-social non-emotional tasks. Taken together, this shows cerebellar neurostimulation confirms causal role socio-emotional cognition, improving skills, may, therefore, have important clinical applications pathologies cognition is impaired.

Язык: Английский

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Potentiation of Motor Adaptation Via Cerebellar tACS: Characterization of the Stimulation Frequency

The Cerebellum, Год журнала: 2024, Номер 23(6), С. 2487 - 2496

Опубликована: Окт. 22, 2024

Motor adaptation is critical to update motor tasks in new or modified environmental conditions. While the cerebellum supports error-based adaptations, its neural implementation partially known. By controlling frequency of cerebellar transcranial alternating current stimulation (c-tACS), we can test influence oscillation from for adaptation. Two independent experiments were conducted. In Experiment 1, 16 participants received four c-tACS protocols (45 Hz, 50 55 and sham) on different days while they practiced a visuomotor task (30 degrees CCW) with variable intensity (within-subject design). 2, 45 separated into three groups effect Hz c-tACS, sham, respectively (between-subject design), performing same fixed (0.9 mA). accelerated when performed only first time, time interval between sessions intensity. The active was ratified where benefits during complete practice period. Reaction velocity, duration reaching are not affected by c-tACS. Cerebellar an effective strategy potentiate adaptations. Frequency-dependent effects gamma band, especially ratify oscillatory profile processes behind This be exploited future interventions enhance learning.

Язык: Английский

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Effects of cerebellar transcranial alternating current stimulation in cerebellar ataxia: study protocol for a randomised controlled trial

Frontiers in Neuroscience, Год журнала: 2023, Номер 17

Опубликована: Апрель 27, 2023

Background Cerebellar ataxia (CA) is a movement disorder that can affect balance and gait, limb movement, oculomotor control, cognition. Multiple system atrophy-cerebellar type (MSA-C) spinocerebellar 3 (SCA3) are the most common forms of CA, for which no effective treatment currently available. Transcranial alternating current stimulation (tACS) non-invasive method brain supposed to alter cortical excitability electrical activity, modulating functional connectivity within brain. The cerebellar tACS modulate outflow cerebellum-linked behavior it proven safe technique humans. Therefore, aim this study 1) examine whether improves severity various non-motor symptoms in homogeneous cohort CA patients consisting MSA-C SCA3, 2) explore time course these effects, 3) assess safety tolerance all participants. Methods/design This 2-week, triple-blind, randomised, sham-controlled study. 164 (MSA-C: 84, SCA3: 80) will be recruited randomly assigned either active or sham tACS, 1:1 ratio. Patients, investigators, outcome assessors unaware allocation. (40 min, 2 mA, ramp-up down periods 10s each) delivered over 10 sessions, distributed two groups five consecutive days with two-day break between. Outcomes assessed after tenth (T1), 1 month (T2) months (T3). primary measure difference between proportion an improvement 1.5 points Scale Assessment Rating Ataxia (SARA) score weeks treatment. In addition, effects on variety symptoms, quality life, autonomic nerve dysfunctions via relative scales. Gait imbalance, dysarthria, finger dexterity objectively valued tools. Finally, magnetic resonance imaging performed possible mechanism effects. Discussion results inform repeated sessions benefit form might novel therapeutic approach consider neuro-rehabilitation setting. Clinical Trial Registration : ClinicalTrials.gov , identifier NCT05557786; https://www.clinicaltrials.gov/ct2/show/NCT05557786 .

Язык: Английский

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Absence of modulatory effects of 6Hz cerebellar transcranial alternating current stimulation on fear learning in men

Frontiers in Human Neuroscience, Год журнала: 2024, Номер 17

Опубликована: Янв. 9, 2024

Fear is a vital defense mechanism to potential threats, which influenced by the cerebellum. While cerebellum’s role in acquiring fear responses well understood, limited knowledge exists about its involvement extinction. In this study, we investigated effects of cerebellar theta band transcranial alternating current stimulation (ctACS) administered during extinction training, based on previous evidence from animal studies suggesting oscillations associative memory formation. To end, thirty-seven healthy right-handed male participants were recruited for two-day differential renewal paradigm. On day 1, they underwent acquisition training context A followed B. 2, recall was tested contexts and One group received ctACS (6 Hz) training. The other sham ctACS. Although both groups demonstrated ability previously learned distinguish between low high threat stimuli, no significant differences observed groups, indicating that at frequency range did not impact acquired study. Nevertheless, using could still be useful future research, including brain imaging studies, better understand how cerebellum involved processes.

Язык: Английский

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Effect of Transcranial Alternating Current Stimulation on Ataxia Symptoms of Spinocerebellar Ataxia Type 3: A Randomized Clinical Trial

Research Square (Research Square), Год журнала: 2024, Номер unknown

Опубликована: Авг. 15, 2024

Currently, there are no treatments to alter the natural course of spinocerebellar ataxia type 3 (SCA3). Transcranial alternating current stimulation (tACS) have sustainable potential alleviate SCA3. Therefore, we conducted a randomized controlled trial enrolling 158 patients with SCA3 investigate safety and efficacy tACS (NCT05557786). Enrolled participants received Active-tACS or Sham-tACS treatment 5 days/week for 2 weeks. The primary outcome was proportion whose Scale Assessment Rating Ataxia score improved by at least 1.5 points compared baseline on assessments immediately after 1-month 3-month follow-up visits. assessed in intention-to-treat population met 32 40 active-tACS group (80%) 4 sham-tACS (OR, 2.04[95% CI, 1.75 2.38; P < 0.001]). These promising findings motivate additional study establish guidelines as clinically recommended cerebellar diseases.

Язык: Английский

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Modulation of Cerebellar Nuclear Activity by Transcranial AC Stimulation in Awake Rats

Опубликована: Июль 15, 2024

Transcranial alternating current stimulation of the cerebellum (ctACS) is an emerging neuromodulation technique that can potentially be leveraged to treat neurological disorders and improve learning in healthy individuals. Yet, effects ctACS on neuronal circuits elusive. We implanted carbon fiber bundle electrodes interpositus nucleus array electrode posterior surface skull for chronic rats. Multi-unit activities (MUA) were recorded from three unanesthetized quietly resting animals during transcranial application stimuli at various frequencies (10 Hz-300 Hz) amplitudes as well after harmaline induced tremors. A frequency-spectrum based method assessing modulation strength MUA was developed. The results show modulated transcranially a range with peak around 50 Hz. This agrees earlier report general [1] although frequency lower. study demonstrates feasibility entraining activity cerebellar nuclear cells awake by AC stimulation, detection tremor MUAs. Future research will directed towards testing this animal model essential tremor.

Язык: Английский

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High-density transcranial direct current stimulation to improve upper limb motor function following stroke: study protocol for a double-blind randomized clinical trial targeting prefrontal and/or cerebellar cognitive contributions to voluntary motion

Research Square (Research Square), Год журнала: 2023, Номер unknown

Опубликована: Янв. 10, 2023

Abstract Background Focal brain lesions following a stroke of the middle cerebral artery induce large-scale network disarray which has potential to impact multiple cognitive and behavioral domains. Over last 20 years, non-invasive neuromodulation via electrical (tCS) stimulation shown modulate motor deficits contribute recovery. However, weak, inconsistent, or at times heterogeneous outcomes using these techniques have also highlighted need for novel strategies assessment their efficacy in ad hoc controlled trials. Methods We here present double-blind, sham-controlled, single-center, randomized clinical trial involving participants having suffered unilateral (MCA) resulting paralysis contralateral upper limb who will undergo 10-days regime (5 days week 2 consecutive weeks) newly designed high-definition transcranial direct current (HD-tDCS) protocol. Clinical scale-based evaluations (e.g., Fugl Meyer, NIHSS, etc.), computer-based assessments (visuo-motor adaptation AX-CPT attention tasks), electroencephalography (resting-state task-evoked EEG) be carried out 3 time-points: I) Baseline, II) Post-tDCS, III) Follow-up. The study consists four-arm comparing on recovery three active anodal tDCS conditions: ipsilesional DLPFC tDCS, contralesional cerebellar combined + sham intervention. In every session, receive min high-density (up 063mA/\({\text{c}\text{m}}^{2}\)) with \({{\pi }\text{c}\text{m}}^{2}\) electrodes. Electrode-scalp positioning relative cortical surface (anodes cathodes) intensities are based biophysical optimization model distribution ensuring 0.25V/m each two chosen targets. Discussion Our gauge therapeutic accumulative sessions HD-tDCS improve dysfunctions presented by patients. parallel, we aim characterizing changes electroencephalographic (EEG) activity as biomarkers effects identify possible interactions between outcomes. work enrich our mechanistic understanding prefrontal contributions function its rehabilitation damage. Trial registration This been registered ClinicalTrials.gov (NCT05329818)

Язык: Английский

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Movement-synchronized cerebellum rhythm coordinates multi-joint movements in young and elderly adults

Biology Open, Год журнала: 2023, Номер 12(3)

Опубликована: Янв. 23, 2023

Rhythmic limb multi-joint movement like locomotion is controlled by intralimb coordination. Intralimb coordination changes entail immediate alterations in patterns and be related with cerebellum function. Synchronized activity has known to modulate the frequency of walking, but not effect only The purpose this study was reveal synchronized unsynchronized on movements unilateral leg young elderly people. To achieve our purpose, we applied transcranial alternating current stimulation during cyclic visual tracking task. results showed that reduction comprehensive synchrony between targets through trials had no significant differences under all stimulus conditions However, variation synchronization significantly smaller condition both groups. Variation remarkably reduced for group. This movement-synchronized contributes reducing fluctuations coordinating movements. Moreover, remarkable

Язык: Английский

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Why is Essential Tremor so Difficult to Treat? A Literature Review

Advanced Journal of Graduate Research, Год журнала: 2023, Номер 13(1), С. 29 - 36

Опубликована: Фев. 24, 2023

Essential tremor (ET) is the most common movement disorder and affects tens of millions individuals worldwide. It characterized by isolated upper-limb tremors for at least three years without other neurological signs or in locations. Despite ET being a widespread disorder, its etiology pathophysiology are poorly understood. This lack understanding poses significant challenges towards development treatments cures. There no cure ET, current limited often insufficient. symptoms can differ greatly between patients, phenotyping only method diagnosis. overlaps with disorders including dystonia Parkinson’s disease, which further complicates diagnosis treatment. Current begin pharmacotherapy, progress to surgical options drug-resistant patients. ongoing research into non-invasive electrical stimulation that may prove be safe effective; however, needed. The aim this review assess literature summarize why so difficult treat. We evaluate efficacy treatments, potential future treatments. four reasons remains treat: 1) unknown pathophysiology, 2) suitable animal model, 3) difficulties diagnosis, 4) absence personalized challenges, an active area novel experimental produce effective therapeutic ET.

Язык: Английский

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