Multimedia Library
Functional connectivity of the anterior cingulate cortex predicts treatment outcome for rTMS in treatment-resistant depression at 3-month follow-up
Repetitive transcranial magnetic stimulation (rTMS) is a first-line treatment for treatment-resistant depression (TRD). The mechanisms of action of rTMS are not fully understood, and no biomarkers are available to assist in clinical practice to predict response to rTMS. This study aimed to demonstrate that after-rTMS clinical improvement is associated with functional connectivity (FC) changes of the subgenual cingulate cortex (sgACC) and rostral anterior cingulate (rACC), and FC of sgACC and rACC might serve as potential predictors for treatment response.Cortical modulation of nociception by galvanic vestibular stimulation: A potential clinical tool?
Vestibular afferents converge with nociceptive ones within the posterior insula, and can therefore modulate nociception. Consistent with this hypothesis, caloric vestibular stimulation (CVS) has been shown to reduce experimental and clinical pain. Since CVS can induce undesirable effects in a proportion of patients, here we explored an alternative means to activate non-invasively the vestibular pathways using innocuous bi-mastoid galvanic stimulation (GVS), and assessed its effects on experimental pain.Cardiovascular differences between sham and active iTBS related to treatment response in MDD
Heart rate in MDD is often dysregulated, expressed in overall higher heart rates (HR) and lower heart rate variability (HRV). Interestingly, HR decelerations have been reported after stimulation of the DLPFC using rTMS, suggesting connectivity between the DLPFC and the heart. Recently, a new form of rTMS called theta burst stimulation (TBS) has been developed. One form of TBS, intermittent TBS (iTBS), delivers 600 pulses in just 3 min.Simulation of transcranial magnetic stimulation in head model with morphologically-realistic cortical neurons
Transcranial magnetic stimulation (TMS) enables non-invasive modulation of brain activity with both clinical and research applications, but fundamental questions remain about the neural types and elements TMS activates and how stimulation parameters affect the neural response.Conditions for numerically accurate TMS electric field simulation
Computational simulations of the E-field induced by transcranial magnetic stimulation (TMS) are increasingly used to understand its mechanisms and to inform its administration. However, characterization of the accuracy of the simulation methods and the factors that affect it is lacking.Cost of focality in TDCS: Interindividual variability in electric fields
In transcranial direct current stimulation (TDCS), electric current is applied via two large electrodes to modulate brain activity. Computational models have shown that large electrodes produce diffuse electric fields (EFs) in the brain, which depends on individual head and brain anatomy. Recently, smaller electrodes as well as novel electrode arrangements, including high-definition TDCS (HD-TDCS) montages, have been introduced to improve the focality of EFs. Here, we investigated whether the EFs of focal montages are more susceptible to interindividual anatomical differences.Using EMG to deliver lumbar dynamic electrical stimulation to facilitate cortico-spinal excitability
Potentiation of synaptic activity in spinal networks is reflected in the magnitude of modulation of motor responses evoked by spinal and cortical input. After spinal cord injury, motor evoked responses can be facilitated by pairing cortical and peripheral nerve stimuli.Transcranial direct current stimulation reduces seizure frequency in patients with refractory focal epilepsy: A randomized, double-blind, sham-controlled, and three-arm parallel multicenter study
Transcranial direct current stimulation (tDCS) has been explored in epilepsy with limited samples, varied parameters, and inconclusive results. We aimed to study the efficacy of tDCS for patients with refractory focal epilepsy.Transcranial focused ultrasound pulsation suppresses pentylenetetrazol induced epilepsy in vivo
Epilepsy is a neurological disorder characterized by abnormal neuron discharge, and one-third of epilepsy patients suffer from drug-resistant epilepsy (DRE). The current management for DRE includes epileptogenic lesion resection, disconnection, and neuromodulation. Neuromodulation is achieved through invasive electrical stimulus including deep brain stimulation, vagus nerve stimulation, or responsive neurostimulation (RNS). As an alternative therapy, transcranial focused ultrasound (FUS) can transcranially and non-invasively modulate neuron activity.Combination of lithium and electroconvulsive therapy (ECT) is associated with higher odds of delirium and cognitive problems in a large national sample across the United States
Lithium is a helpful adjunct to patients undergoing ECT. However, only case reports and limited data suggest increase risk of delirium. Thus, this continues to be a controversial issue.Quantifying acute physiological biomarkers of transcutaneous cervical vagal nerve stimulation in the context of psychological stress
Stress is associated with activation of the sympathetic nervous system, and can lead to lasting alterations in autonomic function and in extreme cases symptoms of posttraumatic stress disorder (PTSD). Vagal nerve stimulation (VNS) is a potentially useful tool as a modulator of autonomic nervous system function, however currently available implantable devices are limited by cost and inconvenience.Adaptive current tDCS up to 4 mA
Higher tDCS current may putatively enhance efficacy, with tolerability the perceived limiting factor.Direct current stimulation-induced synaptic plasticity in the sensorimotor cortex: structure follows function
Non-invasive direct current stimulation (DCS) of the brain induces functional plasticity in vitro and facilitates motor learning across species. The effect of DCS on structural synaptic plasticity is currently unknown.The relationship between individual alpha peak frequency and clinical outcome with repetitive Transcranial Magnetic Stimulation (rTMS) treatment of Major Depressive Disorder (MDD)
The individual α frequency (IAF) has been associated with the outcome of repetitive Transcranial Magnetic Stimulation (rTMS) treatment of Major Depressive Disorder (MDD), but the association has been inconsistent.The effects of repetitive transcranial magnetic stimulation on body weight and food consumption in obese adults: A randomized controlled study
Although some studies have reported significant reductions in food cravings following the single-session of repetitive transcranial magnetic stimulation (rTMS), there is little research on the effects of multi-session of rTMS on food consumption and body weight in obese subjects.Reversible neuroinhibition by focused ultrasound is mediated by a thermal mechanism
Transcranial focused ultrasound (tFUS) at low intensities has been reported to directly evoke responses and reversibly inhibit function in the central nervous system. While some doubt has been cast on the ability of ultrasound to directly evoke neuronal responses, spatially-restricted transcranial ultrasound has demonstrated consistent, inhibitory effects, but the underlying mechanism of reversible suppression in the central nervous system is not well understood.Characterizing and minimizing the contribution of sensory inputs to TMS-evoked potentials
Transcranial magnetic stimulation (TMS) evokes voltage deflections in electroencephalographic (EEG) recordings, known as TMS-evoked potentials (TEPs), which are increasingly used to study brain dynamics. However, the extent to which TEPs reflect activity directly evoked by magnetic rather than sensory stimulation is unclear.Theoretical principles of deep brain stimulation induced synaptic suppression
Deep brain stimulation (DBS) is a successful clinical therapy for a wide range of neurological disorders; however, the physiological mechanisms of DBS remain unresolved. While many different hypotheses currently exist, our analyses suggest that high frequency (∼100 Hz) stimulation-induced synaptic suppression represents the most basic concept that can be directly reconciled with experimental recordings of spiking activity in neurons that are being driven by DBS inputs.MR imaging central thalamic deep brain stimulation restored autistic-like social deficits in the rat
Social deficit is a core symptom in autism spectrum disorder (ASD). Although deep brain stimulation (DBS) has been proposed as a potential treatment for ASD, an ideal target nucleus is yet to be identified. DBS at the central thalamic nucleus (CTN) is known to alter corticostriatal and limbic circuits, and subsequently increase the exploratory motor behaviors, cognitive performance, and skill learning in neuropsychiatric and neurodegenerative disorders.Frequency-specific effects of low-intensity rTMS can persist for up to 2 weeks post-stimulation: A longitudinal rs-fMRI/MRS study in rats
Evidence suggests that repetitive transcranial magnetic stimulation (rTMS), a non-invasive neuromodulation technique, alters resting brain activity. Despite anecdotal evidence that rTMS effects wear off, there are no reports of longitudinal studies, even in humans, mapping the therapeutic duration of rTMS effects.LTD-like plasticity of the human primary motor cortex can be reversed by γ-tACS
Cortical oscillatory activities play a role in regulating several brain functions in humans. However, whether motor resonant oscillations (i.e. β and γ) modulate long-term depression (LTD)-like plasticity of the primary motor cortex (M1) is still unclear.After-effects of 10 Hz tACS over the prefrontal cortex on phonological word decisions
Previous work in the language domain has shown that 10 Hz rTMS of the left or right posterior inferior frontal gyrus (pIFG) in the prefrontal cortex impaired phonological decision-making, arguing for a causal contribution of the bilateral pIFG to phonological processing. However, the neurophysiological correlates of these effects are unclear. The present study addressed the question whether neural activity in the prefrontal cortex could be modulated by 10 Hz tACS and how this would affect phonological decisions.Transcranial direct current stimulation (tDCS) for depression in pregnancy: A pilot randomized controlled trial
Depression in pregnancy negatively affects maternal-child health. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation treatment for depression, has not been evaluated in pregnancy.Real-time estimation of electric fields induced by transcranial magnetic stimulation with deep neural networks
Transcranial magnetic stimulation (TMS) plays an important role in treatment of mental and neurological illnesses, and neurosurgery. However, it is difficult to target specific brain regions accurately because the complex anatomy of the brain substantially affects the shape and strength of the electric fields induced by the TMS coil. A volume conductor model can be used for determining the accurate electric fields; however, the construction of subject-specific anatomical head structures is time-consuming.Prestimulus cortical EEG oscillations can predict the excitability of the primary motor cortex
The motor evoked potentials (MEPs) elicited by single-pulse transcranial magnetic stimulation (TMS) vary considerably at rest, but the mechanism underlying this amplitude variation is largely unknown. We hypothesized that prestimulus EEG oscillations modulate the subsequent MEPs in a state-dependent manner.
