Transcranial Stimulation Techniques Research Articles

Transcranial electrical stimulation (TES) in patients with atopic dermatitis

BACKGROUND: Atopic dermatitis is the most common diseases in dermatology, among the main pathogenetic mechanisms of development of which a complex interaction of a genetically determined defect in the barrier function of the skin, an overactive state of the immune system is considered, and a neurogenic theory of disease development is not excluded, which is based on the relationship of anxiety-stress reactions and neuropsychiatric stresses with the occurrence of pathological changes on the skin. Modern atopic dermatitis therapy is characterized by the appointment of a large number of medications according to clinical recommendations, and the associated increase in allergic and toxic-allergic reactions dictates the need to search for new non-drug treatments for this disease. In order to prevent the pathological effects of stress, as well as to increase resistance to its damaging effects, activation of opioidergic mechanisms may be useful. AIM: To evaluate the effectiveness and acceptability of the transcranial electrical stimulation technique in patients with atopic dermatitis. MATERIALS AND METHODS: A controlled study was conducted among 60 patients with moderate atopic dermatitis, 33 women (55.0%) and 27 men (45.0%) aged 19 to 72 years. Transcranial electrical stimulation was carried out by a pulsed bipolar electrical stimulator with an acoustic effect "TRANSAIR-07", stimulation was carried out by an electric current with a frequency of 77.5 Hz and a duration of 3.5 ms. Patients underwent 10 procedures, 1 time a day, lasting 30 minutes, with a current of 1−3 mA. SCORAD, EASI, IGA, DLQI, HADS, and BDI scales were used to assess the dynamics of clinical manifestations. The assessment was carried out on the first and last day of treatment. RESULTS: During statistical data processing, when comparing the scales in the first and last days of the procedures, depending on the patient groups: the 1st group was the main one, received transcranial electrical stimulation treatment in combination with therapy, according to clinical recommendations, the 2nd group was the control group, received treatment according to clinical recommendations, without the use of transcranial electrical stimulation, significant improvement of itching indicators, clinical manifestations and improvement of quality of life after 4 weeks of therapy in both groups. A statistically more significant dynamics of the indicators of the main clinical scales in favor of combination therapy was established: according to the SCORAD scale ― in the main group from 47.50±2.25 to 21.00±1.00, in the control group from 47.00±2.00 to 39.00±1.75; DLQI ― in the main group from 8.00±2.00 to 2.00±0.75, in the control group ― from 8.50±1.50 to 5.00±1.00. CONCLUSION: The paper presents the positive results of our own research and presents data confirming the clinical effectiveness of transcranial electrostimulation in patients with atopic dermatitis compared with the traditional drug treatment of this disease, which allows us to recommend the treatment regimen we have proposed for widespread implementation in the practice of a dermatovenerologist.

Effects of online tDCS and hf-tRNS on reading performance in children and adolescents with developmental dyslexia: a study protocol for a cross sectional, within-subject, randomized, double-blind, and sham-controlled trial.

Developmental Dyslexia (DD) is a brain-based developmental disorder causing severe reading difficulties. The extensive data on the neurobiology of DD have increased interest in brain-directed approaches, such as transcranial direct current stimulation (tDCS), which have been proposed for DD. While positive outcomes have been observed, results remain heterogeneous. Various methodological approaches have been employed to address this issue. However, no studies have compared the effects of different transcranial electrical stimulation techniques (e.g., tDCS and transcranial random noise stimulation, tRNS), on reading in children and adolescents with DD. The present within-subject, double-blind, and sham-controlled trial aims to investigate the effects of tDCS and hf-tRNS on reading in children and adolescents with DD. Participants will undergo three conditions with a one-week interval session: (A) single active tDCS session; (B) single active hf-tRNS session; and (C) single sham session (tDCS/hf-tRNS). Left anodal/right cathodal tDCS and bilateral tRNS will be applied over the temporo-parietal regions for 20 min each. Reading measures will be collected before and during each session. Safety and blinding parameters will be recordered. We hypothesize that tRNS will demonstrate comparable effectiveness to tDCS in improving reading compared to sham conditions. Additionally, we anticipate that hf-tRNS will exhibit a similar safety profile to tDCS. This study will contribute novel insights into the effectiveness of hf-tRNS, expediting the validation of brain-based treatments for DD.

The effect of transcranial direct current stimulation on bilateral asymmetry and joint angles of the lower limb for females when crossing obstacles

BackgroundGait asymmetry is often accompanied by the bilateral asymmetry of the lower limbs. The transcranial direct current stimulation (tDCS) technique is widely used in different populations and scenarios as a potential tool to improve lower limb postural control. However, whether cerebral cortex bilateral tDCS has an interventional effect on postural control as well as bilateral symmetry when crossing obstacles in healthy female remains unknown.MethodsTwenty healthy females were recruited in this prospective study. Each participant walked and crossed a height-adjustable obstacle. Two-way repeated ANOVA was used to evaluate the effect of group (tDCS and sham-tDCS) and height (30%, 20%, and 10% leg length) on the spatiotemporal and maximum joint angle parameters for lower limb crossing obstacles. The Bonferroni post-hoc test and paired t-test were used to determine the significance of the interaction effect or main effect. The statistically significant differences were set at p < 0.05.ResultsThe Swing time (SW) gait asymmetry (GA), Stance time (ST) GA, leading limb hip-knee-ankle maximum joint angles and trailing limb hip-knee maximum joint angles decreased in the tDCS condition compared to the sham-tDCS condition at 30%, 20% leg’s length crossing height except for 10% leg’s length, whereas there was a significant decrease in SW/ST GA between the tDCS condition and the sham-tDCS condition at 30%, 20%, 10% leg’s length crossing height (P < 0.05).ConclusionWe conclude that tDCS intervention is effective to reduce bilateral asymmetry in spatio-temporal parameters and enhance dynamic balance in female participants during obstacle crossing when the heights of the obstacles were above 10% of the leg’s length.Trial registration NoChiCTR2100053942 (date of registration on December 04, 2021). Prospectively registered in the Chinese Clinical Trial Registry.

Does Electrical Brain Stimulation with Transcranial Direct Current Stimulation (TDCS) Technique Reduce Blood Sugar in Patients with Type 2 Diabetes?

The Article Abstract is not available.

69 Transcranial Random Noise Stimulation Facilitates Phonemic Verbal Fluency and Convergent Thinking in Multilingual Healthy Adults.

Objective:The aim of the present study was to analyse the effects of the transcranial random noise stimulation (tRNS) technique when placed on the left dorsolateral prefrontal cortex (L-DPFC) and left inferior frontal gyrus (L-IFG), for the improvement of verbal fluency performance and creativity skills in a group of multilingual healthy adults.Participants and Methods:Fifty healthy adults, aged 18-47 years, participated in the study. All of them were native Spanish speakers of which three were bilingual (Spanish and English) and 47 were multilingual (Spanish, Basque and English). The study had a randomized, counterbalanced, double-blind, sham-controlled design. The participants were randomly allocated to either a tRNS active group or a placebo-control group. All participants were tested individually in one session divided into three parts: (1) baseline, (2) online, and (3) offline assessment. In the active condition, a 1.5mA current (100-500 Hz) was delivered for 20 minutes (online phase). Participants’ verbal fluency was assessed through semantic and phonemic verbal fluency tasks in three different languages (Spanish, Basque and English), while creativity was assessed in their native language with the Remote Associations Test (RAT, pre and post forms) for convergent thinking, and with the Unusual Uses subtest (UU, pre and post forms) for divergent thinking. In addition, the linguistic profile of the participants was evaluated with the Language Experience and Proficiency Questionnaire (LEAP-Q), and their processing speed and cognitive flexibility were assessed with the Stroop Color and Word Test (SCWT).Results:The results showed significant differences in phonemic fluency between the groups during the online assessment in Spanish (F= 5.31, p = 0.026), and in the offline assessments in Spanish (F=6.44, p = 0.015) and English (F=10.80, p = 0.002), with participants in the active condition performing better. While no differences were observed in the performance of the groups in verbal fluency in Basque, neither in the online (F=1.06, p = 0.31), nor in the offline assessment (F=2.62, p = 0.11). Furthermore, no significant differences were observed between groups in semantic verbal fluency tasks in any of the languages, neither during stimulation nor offline. However, there were no differences between conditions in the online (Spanish, F=0.86, p = 0.35; English, F=2.95, p = 0.09; and Basque, F=0.01 p = 0.94) and offline (Spanish, F=2.53, p = 0.11; English, F=0.74, p = 0.39; and Basque, F=1.39, p = 0.24) semantic tasks. In creativity, significant differences were observed between groups on the RAT (F=9.58, p = 0.003), while no differences were observed in the performance of any of the three dimensions of the UU (Originality, F=0.44, p = 0.51; Flexibility, F=0.42, p = 0.51; Fluency, F=0.69, p = 0.41). In the SCWT, statistically significant differences were only observed in the colour-word part (F=7.60, p = 0.008) during the online assessment, showing a better performance of the participants under the tRNS condition compare to the sham condition.Conclusions:The results obtained in this study suggest that the excitatory effects of tRNS over the L-DLPFC L-IFG could contribute to the improvement of phonemic verbal fluency and verbal convergent thinking, in healthy individuals.

Effects of Transcranial Electrical Stimulation on Gambling and Gaming: A Systematic Review of Studies on Healthy Controls, Participants with Gambling/Gaming Disorder, and Substance Use Disorder.

Gambling disorder (GD) and internet gaming disorder (IGD) are formally recognized behavioral addictions with a rapidly growing prevalence and limited treatment options. Recently, transcranial electrical stimulation (tES) techniques have emerged as potentially promising interventions for improving treatment outcomes by ameliorating cognitive functions implicated in addictive behaviors. To systematize the current state of evidence and better understand whether and how tES can influence gambling and gaming-related cognitive processes, we conducted a PRISMA-guided systematic review of the literature, focusing on tES effects on gaming and gambling in a diverse range of population samples, including healthy participants, participants with GD and IGD, as well as participants with substance abuse addictions. Following the literature search in three bibliographic databases (PubMed, Web of Science, and Scopus), 40 publications were included in this review, with 26 conducted on healthy participants, 6 focusing on GD and IGD patients, and 8 including participants with other addictions. Most of the studies targeted the dorsolateral prefrontal cortex, using transcranial direct current stimulation (tDCS), and assessed the effects on cognition, using gaming and gambling computerized cognitive tasks measuring risk taking and decision making, e.g., balloon analogue risk task, Iowa gambling task, Cambridge gambling task, etc. The results indicated that tES could change gambling and gaming task performances and positively influence GD and IGD symptoms, with 70% of studies showing neuromodulatory effects. However, the results varied considerably depending on the stimulation parameters, sample characteristics, as well as outcome measures used. We discuss the sources of this variability and provide further directions for the use of tES in the context of GD and IGD treatment.

Application of noninvasive hardware technique of transcranial electrical stimulation (TES) in patients with atopic dermatitis

BACKGROUND: Transcranial electrostimulation (TES therapy) is a physiotherapeutic non-invasive technology that allows painlessly, selectively and strictly dosed activation of certain brain structures producing endogenous opioid peptides by modulating activity in these brain regions that are involved in the processing of pain and itching signals. Originally, this technique was used as an electronarcosis, then the scope of TES therapy in medicine expanded and began to be used in neurology, gynecology, urology, gastroenterology. The efficacy of its use in dermatology as an antipruritic action remain poorly understood.&#x0D; AIM: the purpose of the pilot study was to evaluate the effectiveness and acceptability of the use of non-invasive TES therapy in patients with atopic dermatitis.&#x0D; MATERIAL AND METHODS: According to the existing concept, itching is considered as a kind of pain sensation caused by an altered threshold level of nerve endings in the skin that perceive pain. Given this similarity of the mechanisms of pain and itching, noninvasive brain stimulation can simultaneously reduce itching, which opens up broad prospects for its further use in itchy dermatoses.&#x0D; A pilot controlled study was conducted, the object of the study was patients with moderate atopic dermatitis (9 women and 6 men) aged 19 to 48 years. TES therapy was carried out by a pulsed bipolar electrical stimulator with acoustic effect "TRANSAIR-07" according to the standard method. All patients who received a course of TES monotherapy underwent 10 procedures, 1 time a day, lasting 3040 minutes, with a current of 13 mA. To assess the dynamics of clinical manifestations of atopic dermatitis and the severity of the disease, the following scales were used: SCORAD, EASI, IGA, DLQI, HADS, BDI. The assessment was carried out twice: the first time on the day of diagnosis verification and again on the 10th day of treatment.&#x0D; RESULTS: As a result of the treatment, there was a decrease in itching from 5 to 2 points, an improvement in mood from 5 to 1 point, an increase in performance from 4 to 1 point, a decrease in anxiety and depression from 4 to 2 points. With a general assessment of the dynamics of the indicators of the applied clinical scales (SCORAD, EASI, IGA, DLQI, HADS, BDI), the total average effectiveness in the form of parameter improvement amounted to 66.25% reduction by the end of the 10-day course.&#x0D; CONCLUSION: The work presents the modern aspects of the application of non-invasive hardware transcranial electrical stimulation technique. The positive results of our own pilot study are presented and data confirming the clinical efficacy of transcranial electrical stimulation in patients with atopic dermatitis are presented, which determines the prospect of developing a combined application of TES therapy for this persistent disease.

Transcranial electrical stimulation technique for induction of unilateral motor evoked potentials

ObjectiveTranscranial electrical stimulation motor evoked potentials (TES-MEP) are widely used to monitor motor function; however, broad current spread and induced body movement are limitations of this technique. We herein report a localized stimulation technique for TES-MEP that induces unilateral MEP responses. MethodsThe stimulation of C1(+)-C4(-) or C2(+)–C3(-) was performed to induce right- or left-sided muscle contraction, respectively, in 70 patients. Electromyography was recorded by placing electrodes on the bilateral abductor pollicis brevis (APB) and abductor hallucis (AH) muscles. Stimulation conditions were regulated in the range to induce unilateral muscle contractions contralateral to the anodal stimulation. The thresholds and amplitudes of TES-MEP were retrospectively analyzed. ResultsThe thresholds of APB were lower than those of AH in 47 patients, AH thresholds were lower than those of APB in 6 patients, and both APB and AH started to respond at the same intensity in 15 patients. This technical stimulation induced contralateral limb contractions with a suprathreshold stimulation of 129.4 ± 35.6 mA (mean ± standard deviation) in 68 patients (97%). Amplitudes in the suprathreshold stimulation of APB and AH responses were 727.5 ± 695.7 and 403.3 ± 325.7 μV, respectively. ConclusionsThe C1(+)–C4/C2(+)–C3(-) stimulation in TES-MEP enables a localized stimulation to induce unilateral MEP responses. SignificanceOur stimulation technique enables the stable and safe monitoring of unilateral limbs, and contributes to the reliable monitoring of motor function in neurosurgery.

Comparison of Two Electrode Placement Methods in Transcranial Direct Current Stimulation for Parkinson's Disease

Purpose: Therapeutic electrical stimulation of deep brain structures, such as the subthalamic nucleus and the Globus Pallidus (GP), is widely accepted as a treatment tool for patients with Parkinson's Disease (PD). Electrical stimulation of the cerebral cortex with electrodes or transcranial stimulation can increase motor function among PD patients. The present study aimed to evaluate the effects of non-invasive cortical stimulation with simulation of transcranial Direct Current Stimulation (tDCS) technique on parts of the basal ganglia among PD patients.&#x0D; Materials and Methods: tDCS was simulated using two different electrode placement methods (anodal stimulation of the primary motor cortex (M1) and anodal stimulation of the Dorsolateral Prefrontal Cortex (DLPFC)) and We evaluated the excitation procedure in the target area based on the excitation current distribution in GP and Subthalamic Nucleus according to the patient's condition in both electrode methods. All simulations were performed using head Magnetic Resonance Imaging (MRI) images of four people with PD. Also, according to the excitation current distribution obtained from the previous step, we studied how the excitation current distributed in the target areas is affected by using a model of the basal ganglia so that based on the membrane potential of each excitation in these areas, in all four patients, we compare both electrode-installation methods in a functional way. The effectiveness of brain stimulation was also studied using a basal ganglia model. Considering the membrane potential of GP and Subthalamic Nucleus regions, the effectiveness of each electrode placement method was evaluated in the Basal Ganglia (BG) model.&#x0D; Results: According to the results, direct current stimulation was propagated through electrodes placed on the scalp throughout the model. Also, anodal stimulation of the M1 had a better stimulation of GP and subthalamic nucleus than anodal stimulation of the DLPFC.&#x0D; Conclusion: Although, the procedures for performing tDCS and invasive brain stimulation in PD are different, the results show that this treatment can be appropriate and improve motor function in patients with PD.

A method for non-destructive microwave focusing for deep brain and tissue stimulation.

Non-invasive stimulation of biological tissue is highly desirable for several biomedical applications. Of specific interest are methods for tumor treatment, endometrial ablation, and neuro-modulation. In traditional neuro-modulation, single- and multi-coil transcranial stimulation techniques in low oscillation frequencies are utilized to non-invasively penetrate the skull and elicit action potentials in cortical neurons. Although these methods have been proven effective, tightly focusing these signals to localized regions is difficult. In recent years, microwave (MW) methods have seen an increase usage as a minimally invasive treatment modality for ablation and neuro-stimulation. Unlike low frequency signals, MW signals can be focused to localized sub-centimeter regions. In this work we demonstrate that a three-dimensional array of MW antennas can be used to tightly focus signals to a localized region in space within the human body with MW frequencies. Assuming an array of small MW loop antennas are placed around the body, the optimal amplitude and phase of each array element can be accurately determined to match an arbitrary desired field profile. The major innovation of the presented method is that the fields that penetrate the biological region are determined via computing numerical Green's functions (NGF) that are then used to drive an optimization algorithm. Using simplified models of regions in the human body, it is shown that the MW fields at 1 GHz can be focused to sub-centimeter sized "hot spots" at depths of several centimeters. The algorithm can be easily extended to more realistic models of the human body or for non-biological applications.

Clinical Practice Guidelines for the Use of Transcranial Direct Current Stimulation in Psychiatry.

Clinical Practice Guidelines for the Use of Transcranial Direct Current Stimulation in Psychiatry.

Potential application of Transcranial Electrical Stimulation (tES) techniques in the context of covid-19 clinical course: From theory to real-world application

Potential application of Transcranial Electrical Stimulation (tES) techniques in the context of covid-19 clinical course: From theory to real-world application

Effects of transcranial electrical stimulation techniques on foreign vocabulary learning

Although the use of transcranial electrical stimulation (tES) techniques on healthy population has been linked to facilitating language learning, studies on their effects on foreign language learning processes are scarce and results remain unclear. The objective of this study was to analyze whether tES enhances foreign language learning processes. Sixty-four healthy native Spanish-speaking participants were randomly assigned to four groups (transcranial direct current, transcranial random noise, tDCS-tRNS stimulation, or sham). They completed two intervention sessions with a two-week gap in between. During the first session the participants received stimulation (1.5 mA) while learning new English words and then performed recall and recognition tasks. Learning was assessed at follow-up, two weeks later. No differences in learning between groups were observed in the first session (F(1,61)= .86; p = .36). At follow-up, significantly higher learning accuracy was observed after tRNS compared to sham (p = .037). These results suggest that tRNS could be helpful in improving the processes involved in foreign language vocabulary learning.

Electric Fields Induced in the Brain by Transcranial Electric Stimulation: A Review of In Vivo Recordings.

Transcranial electrical stimulation (tES) techniques, such as direct current stimulation (tDCS) and transcranial alternating current stimulation (tACS), cause neurophysiological and behavioral modifications as responses to the electric field are induced in the brain. Estimations of such electric fields are based mainly on computational studies, and in vivo measurements have been used to expand the current knowledge. Here, we review the current tDCS- and tACS-induced electric fields estimations as they are recorded in humans and non-human primates using intracerebral electrodes. Direct currents and alternating currents were applied with heterogeneous protocols, and the recording procedures were characterized by a tentative methodology. However, for the clinical stimulation protocols, an injected current seems to reach the brain, even at deep structures. The stimulation parameters (e.g., intensity, frequency and phase), the electrodes’ positions and personal anatomy determine whether the intensities might be high enough to affect both neuronal and non-neuronal cell activity, also deep brain structures.

Cerebellar transcranial current stimulation - An intraindividual comparison of different techniques.

Transcranial current stimulation (tCS) techniques have been shown to induce cortical plasticity. As an important relay in the motor system, the cerebellum is an interesting target for plasticity induction using tCS, aiming to modulate its excitability and connectivity. However, until now it remains unclear, which is the most effective tCS method for inducing plasticity in the cerebellum. Thus, in this study, the effects of anodal transcranial direct current stimulation (tDCS), 50 Hz transcranial alternating current stimulation (50 Hz tACS), and high frequency transcranial random noise stimulation (tRNS) were compared with sham stimulation in 20 healthy subjects in a within-subject design. tCS was applied targeting the cerebellar lobe VIIIA using neuronavigation. We measured corticospinal excitability, short-interval intracortical inhibition (SICI), short-latency afferent inhibition (SAI), and cerebellar brain inhibition (CBI) and performed a sensor-based movement analysis at baseline and three times after the intervention (post1 = 15 min; post2 = 55 min; post3 = 95 min). Corticospinal excitability increased following cerebellar tACS and tRNS compared to sham stimulation. This effect was most pronounced directly after stimulation but lasted for at least 55 min after tACS. Cortico-cortical and cerebello-cortical conditioning protocols, as well as sensor-based movement analyses, did not change. Our findings suggest that cerebellar 50 Hz tACS is the most effective protocol to change corticospinal excitability.

Effects of online parietal transcranial electric stimulation on associative memory: a direct comparison between tDCS, theta tACS, and theta-oscillatory tDCS

Associative memory (AM) is the ability to remember and retrieve multiple items bound together. Previous studies aiming to modulate AM by various transcranial electric stimulation (tES) techniques were inconclusive, although overall suggestive that tES could be a tool for AM enhancement. However, evidence from a direct comparison between different tES techniques is lacking. Here, in a sham-controlled cross-over experiment, we comparatively assessed the effects of three types of tES—anodal tDCS, theta-band transcranial alternating current stimulation (tACS), and theta-oscillatory tDCS (otDCS), delivered over the left posterior parietal cortex, during a short-term digit-color AM task with cued-recall. The effects were tested in 40 healthy young participants while both oscillatory tES were delivered at a previously determined individual theta frequency (4–8 Hz). All three active stimulations facilitated the overall AM performance, and no differences could be detected between them on direct comparison. However, unlike tDCS, the effects of which appeared to stem mainly from the facilitation of low-memory demand trials, both theta-modulated tACS and otDCS primarily promoted AM in high memory demand trials. Comparable yet differential effects of tDCS, theta tACS, and otDCS could be attributed to differences in their presumed modes of action.

Spherical harmonics based model of electric field effects on neocortical neurons

Abstract Transcranial electrical stimulation (tES) techniques generate electric fields in the brain whose effects on single neurons can be approximated from the cable equation as a membrane potential perturbation that is proportional to the membrane length constant (lambda). This is referred to as the lambda-E model and is a simple mechanistic approach that assumes that the membrane perturbation can be modeled as the dot product of a vector parallel to the orthodromic direction of cortical neurons with the electric field, multiplied by lambda. We propose a more general way to represent the model of the membrane perturbation as a function of the magnitude and angular orientation of the E-field, using a spherical harmonics expansion that can capture the dependence of the perturbation on electric field direction. In this representation, the lambda-E model corresponds to the first-order degree (l=1) term of the expansion. This approach can represent the three-dimensional response of a specific cell part, obtained experimentally. Here we employ it using synthetic data from realistic neocortical cell models in a DC field in the tDCS regime, fitting the coefficients for the membrane responses. We use realistic reconstructions of the somatosensory cortex from the Blue Brain Project to simulate the response of different pyramidal cells and interneurons to electric fields of 1 V/m as a function of the orientation of the field with respect to the cell using the NEURON simulation environment. We report membrane perturbation values comparable to those in the literature, extend it to different cell types, and provide the spherical harmonic coefficient profile for each neuron. Finally, we provide an azimuth-independent version of the model providing an averaged response that only depends on the electric field vector and the cortical surface. We believe this method can improve the accuracy and detail of real life simulation-based stimulation. Keywords: Electric field coupling, Multicompartment models, tES, NEURON

Fast or Slow? A Comparison Between Two Transcranial Electrical Stimulation Techniques for Eliciting Motor-Evoked Potentials During Supratentorial Surgery.

During intraoperative neurophysiological monitoring of motor pathways, two types of transcranial electrical stimulation are available, i.e., constant-current and constant-voltage stimulation. Few previous studies, performed only during spinal surgery, analyzed and compared them during intraoperative neurophysiological monitoring. The aim of our study was to compare these two stimulation techniques for eliciting motor-evoked potentials during intraoperative neurophysiological monitoring in a group of patients affected by supratentorial lesions. Supratentorial lesions from 16 patients were retrospectively collected and analyzed. Motor-evoked potentials were performed only from transcranial electrical stimulation because the inability to place the subdural strip electrodes correctly did not permit to perform direct cortical stimulation. At the beginning of surgery, in each patient, motor-evoked potentials were monitored by using both "fast-charge" constant-voltage and "slow-charge" constant-current stimulation. Several neurophysiological parameters were collected and compared between the two stimulation techniques by means of statistical analysis. "Fast-charge" constant-voltage stimulation allowed statistically higher efficiency rates for eliciting motor-evoked potentials compared with "slow-charge" constant-current stimulation, both for upper and lower limbs. We also found that threshold and maximal charge as well as charge density were significantly lower during constant-voltage stimulation, thus lowering the potential tissue damage. "Fast-charge" constant-voltage transcranial electrical stimulation is feasible and safe during intraoperative neurophysiological monitoring for supratentorial surgery and may be preferable to "slow-charge" constant-current stimulation.

Non-invasive brain stimulation in neurorehabilitation

Transcranial electric stimulation techniques (tDCS; tACS; tRNS) and repetitive transcranial magnetic stimulation (rTMS) allow increasing or decreasing the excitability of corticospinal or cortico-cortical pathways depending on variables such as intensity, stimulation duration, number and frequency of stimulation pulses in rTMS and others. Electric techniques provide the potential for home treatment whereas rTMS techniques are bound to outpatient medical infrastructure. Transcranial ultrasound stimulation is on the way to supplement the therapeutic repertoire. Different techniques may be combined. The largest medical need in neurorehabilitation concerns motor stroke and aphasia. Local strokes not only impede the affected but also remote areas. Essentially two techniques can be pursued, facilitating directly the affected area or modulating remote areas providing either facilitatory or inhibitory input to the target area. Electric interference stimulation may be used to selectively stimulate deeper areas to a certain extent. Network analysis methods provide information on disturbed network activities usually by either EEG or fMRI. Multichannel electric stimulation methods may try to restitute normal network activity. Co-application of drugs may impede or facilitate stimulation effects. An overview will be given on these technical aspects and on already validated techniques in clinical neurorehabilitation. Most promising near future stimulation prospects will be addressed also in the context of cost-effectiveness.

Effects of mindful breath awareness and muscle relaxation and transcranial electrical stimulation techniques on improving blood pressure status in patients with type 2 diabetes

ObjectiveThe present study aimed to determine the effects of mindful breath awareness & muscle relaxation (MBMR) and transcranial electrical stimulation (tCES) techniques on improving the systolic and diastolic blood pressure status in patients with type 2 diabetes. MethodsThe research method was randomized controlled trial (RCT) using split-plot ANOVA (SPANOVA). Thirty patients were selected through purposive sampling from Bonab County Diabetes Association (Iran) and were randomly divided into three 10-member groups, namely MBMR, tCES, and MBMR+tCES groups. Participants received their group interventions in 10 individual sessions. All patients were evaluated for systolic and diastolic blood pressure at two stages, before and immediately after each session. SPANOVA and Bonferroni pairwise comparison tests were used for data analysis. ResultsThe results indicated that the MBMR and tCES techniques, alone and in combination, had significant and equal effects on reducing diastolic blood pressure, but the MBMR treatment was more effective in the systolic blood pressure than the tCES. ConclusionsThe MBMR and tCES techniques were effective and safe in treating hypertension in patients with type 2 diabetes.