Investigating the Working Mechanism of Transcranial Direct Current Stimulation.

Background: Transcranial direct current stimulation (tDCS) is used to modulate neuronal activity, but the exact mechanism of action (MOA) is unclear. This study investigates tDCS-induced modulation of the corticospinal excitability and the underlying MOA. By anesthetizing the scalp before applying tDCS and by stimulating the cheeks, we investigated whether stimulation of peripheral and/or cranial nerves contributes to the effects of tDCS on corticospinal excitability.

Exploration of Theta Burst-Induced Modulation of Transcranial Magnetic Stimulation-Evoked Potentials Over the Motor Cortex.

Objectives: This study investigates the way theta burst stimulation (TBS) applied to the motor cortex (M1) affects TMS-evoked potentials (TEPs). There have been few direct comparisons of continuous TBS (cTBS) and intermittent TBS (iTBS), and there is a lack of consensus from existing literature on the induced effects. We performed an exploratory trial to assess the effect of M1-cTBS and M1-iTBS on TEP components.

Evaluating Robustness of Brain Stimulation Biomarkers for Depression: A Systematic Review of Magnetic Resonance Imaging and Electroencephalography Studies.

Noninvasive brain stimulation (NIBS) treatments have gained considerable attention as potential therapeutic intervention for psychiatric disorders. The identification of reliable biomarkers for predicting clinical response to NIBS has been a major focus of research in recent years. Neuroimaging techniques, such as electroencephalography (EEG) and functional magnetic resonance imaging (MRI), have been used to identify potential biomarkers that could predict response to NIBS.

Accelerated Repetitive Transcranial Magnetic Stimulation to Treat Major Depression: The Past, Present, and Future.

Repetitive transcranial magnetic stimulation (rTMS) is an effective and evidence-based therapy for treatment-resistant major depressive disorder. A conventional course of rTMS applies 20-30 daily sessions over 4-6 weeks. The schedule of rTMS delivery can be accelerated by applying multiple stimulation sessions per day, which reduces the duration of a treatment course with a predefined number of sessions.

Social and contextual influences on eating pathology in transgender and nonbinary adults.

Eating pathology (EP) is reported at alarmingly high rates among transgender and nonbinary (TNB) people. The present study investigates key associations between experiences that are common in TNB populations and EP. TNB individuals located within the United States ( = 212) who self-identified as currently experiencing disordered eating or an eating disorder were recruited from social media outlets and completed an online survey that included measures of EP, discrimination-based trauma symptoms, internalized transphobia, and gender dysphoria.

Continuous theta burst stimulation for drug-resistant epilepsy.

Introduction: Repetitive transcranial magnetic stimulation (rTMS) may have anti-epileptic effects, especially in patients with neocortical lesions. Initial clinical trials demonstrated that the duration of the seizure reducing effect is relatively short-lived. In the context of a chronic condition like epilepsy, theta burst stimulation (TBS) may represent a potential solution in optimizing treatment practicality and durability as it was demonstrated to be associated with longer-lasting after-effects.

Recent Advances in the Use of Focused Ultrasound as a Treatment for Epilepsy.

Epilepsy affects about 1% of the population. Approximately one third of patients with epilepsy are drug-resistant (DRE). Resective surgery is an effective treatment for DRE, yet invasive, and not all DRE patients are suitable resective surgery candidates.

Personalized tDCS for Focal Epilepsy-A Narrative Review: A Data-Driven Workflow Based on Imaging and EEG Data.

Conventional transcranial electric stimulation(tES) using standard anatomical positions for the electrodes and standard stimulation currents is frequently not sufficiently selective in targeting and reaching specific brain locations, leading to suboptimal application of electric fields. Recent advancements in in vivo electric field characterization may enable clinical researchers to derive better relationships between the electric field strength and the clinical results. Subject-specific electric field simulations could lead to improved electrode placement and more efficient treatments.

[A 51-year-old man with primary progressive aphasia].

Primary progressive aphasia (PPA) is a form of dementia in which brain circuits responsible for language and speech show progressive impairments. Based on consensus criteria PPA is divided into 3 main variants: a nonfluent/agrammatic, a semantic and a logopenic variant. Each variant has specific clinical characteristics, including neuropsychiatric symptoms, and is associated with different neuropathological findings.

Investigating the Effect of Transcutaneous Auricular Vagus Nerve Stimulation on Cortical Excitability in Healthy Males.

Objectives: As a potential treatment for epilepsy, transcutaneous auricular vagus nerve stimulation (taVNS) has yielded inconsistent results. Combining transcranial magnetic stimulation with electromyography (TMS-EMG) and electroencephalography (TMS-EEG) can be used to investigate the effect of interventions on cortical excitability by evaluating changes in motor evoked potentials (MEPs) and TMS-evoked potentials (TEPs). The goal of this study is to objectively evaluate the effect of taVNS on cortical excitability with TMS-EMG and TMS-EEG.

Personalizing Repetitive Transcranial Magnetic Stimulation Parameters for Depression Treatment Using Multimodal Neuroimaging.

Repetitive transcranial magnetic stimulation (rTMS) is a tool that can be used to administer treatment for neuropsychiatric disorders such as major depressive disorder, although the clinical efficacy is still rather modest. Overly general stimulation protocols that consider neither patient-specific depression symptomology nor individualized brain characteristics, such as anatomy or structural and functional connections, may be the cause of the high inter- and intraindividual variability in rTMS clinical responses. Multimodal neuroimaging can provide the necessary insights into individual brain characteristics and can therefore be used to personalize rTMS parameters.

GIS in the jungle: Experiential Environmental Education (EEE) in Panama.

A University of Redlands travel course to Panama builds on Monty Hempel's legacy in environmental studies, Experiential Environmental Education, and geographic information systems (GIS) instruction at the University of Redlands. It follows his experience developing social relationships in Panama, and nearly 20 years leading an EEE travel course to Palau. This Panama course, nicknamed "GIS in the Jungle," tasks students with activities such as trail mapping, gathering original data with unmanned aerial vehicles (UAV), landcover mapping of pastures and forests, and visualizing the distribution of above-ground forest carbon content.

Cortical Thickness in the Right Anterior Cingulate Cortex Relates to Clinical Response to Left Prefrontal Accelerated Intermittent Theta Burst Stimulation: An Exploratory Study.

Objectives: Accelerated intermittent theta burst stimulation (aiTBS) is a promising treatment option for depressed patients. However, there is a large interindividual variability in clinical effectiveness and individual biomarkers to guide treatment outcome are needed.

Materials And Methods: Here, the relation between cortical thickness and clinical response (17-item Hamilton Depression Rating Scale) was studied using anatomical MRI data of 50 depressed patients who were included in a randomized, sham-controlled, double-blinded, cross-over aiTBS design (NCT01832805).

EEG Functional Connectivity is a Weak Predictor of Causal Brain Interactions.

In recent years there has been an explosion of research evaluating resting-state brain functional connectivity (FC) using different modalities. However, the relationship between such measures of FC and the underlying causal brain interactions has not been well characterized. To further characterize this relationship, we assessed the relationship between electroencephalography (EEG) resting state FC and propagation of transcranial magnetic stimulation (TMS) evoked potentials (TEPs) at the sensor and source level in healthy participants.

Indirect frontocingulate structural connectivity predicts clinical response to accelerated rTMS in major depressive disorder.

Background: Repetitive transcranial magnetic stimulation (rTMS) is an established treatment for major depressive disorder (MDD), but its clinical efficacy remains rather modest. One reason for this could be that the propagation of rTMS effects via structural connections from the stimulated area to deeper brain structures (such as the cingulate cortices) is suboptimal.

Methods: We investigated whether structural connectivity — derived from diffusion MRI data — could serve as a biomarker to predict treatment response.

Accelerated intermittent theta burst stimulation in major depression induces decreases in modularity: A connectome analysis.

Accelerated intermittent theta burst stimulation (aiTBS) is a noninvasive neurostimulation technique that shows promise for improving clinical outcome in patients suffering from treatment-resistant depression (TRD). Although it has been suggested that aiTBS may evoke beneficial neuroplasticity effects in neuronal circuits, the effects of aiTBS on brain networks have not been investigated until now. Fifty TRD patients were enrolled in a randomized double-blind sham-controlled crossover trial involving aiTBS, applied to the left dorsolateral prefrontal cortex.

Focal application of accelerated iTBS results in global changes in graph measures.

Graph analysis was used to study the effects of accelerated intermittent theta burst stimulation (aiTBS) on the brain's network topology in medication-resistant depressed patients. Anatomical and resting-state functional MRI (rs-fMRI) was recorded at baseline and after sham and verum stimulation. Depression severity was assessed using the Hamilton Depression Rating Scale (HDRS).

Left prefrontal neuronavigated electrode localization in tDCS: 10-20 EEG system versus MRI-guided neuronavigation.

Transcranial direct current stimulation (tDCS) involves positioning two electrodes at specifically targeted locations on the human scalp. In neuropsychiatric research, the anode is often placed over the left dorsolateral prefrontal cortex (DLPFC), while the cathode is positioned over a contralateral cephalic region above the eye, referred-to as the supraorbital region. Although the 10-20 EEG system is frequently used to locate the DLPFC, due to inter-subject brain variability, this method may lack accuracy.

Repetitive transcranial magnetic stimulation for the treatment of refractory epilepsy.

Introduction: Repetitive transcranial magnetic stimulation (rTMS) is an established non-invasive neurostimulation technique that is able to induce neuromodulatory effects outlasting the duration of the stimulation train. The cortical excitability disturbance in epilepsy provides a rationale for investigating the efficacy of low-frequency rTMS as a treatment for epilepsy patients. Sofar clinical trials in epilepsy patients have shown conflicting results ranging from ineffective to very effective.

Technical aspects of neurostimulation: Focus on equipment, electric field modeling, and stimulation protocols.

Neuromodulation is a field of science, medicine, and bioengineering that encompasses implantable and non-implantable technologies for the purpose of improving quality of life and functioning of humans. Brain neuromodulation involves different neurostimulation techniques: transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), vagus nerve stimulation (VNS), and deep brain stimulation (DBS), which are being used both to study their effects on cognitive brain functions and to treat neuropsychiatric disorders. The mechanisms of action of neurostimulation remain incompletely understood.

Cognitive deterioration in adult epilepsy: Does accelerated cognitive ageing exist?

A long-standing concern has been whether epilepsy contributes to cognitive decline or so-called 'epileptic dementia'. Although global cognitive decline is generally reported in the context of chronic refractory epilepsy, it is largely unknown what percentage of patients is at risk for decline. This review is focused on the identification of risk factors and characterization of aberrant cognitive trajectories in epilepsy.

Physiological consequences of abnormal connectivity in a developmental epilepsy.

Objective: Many forms of epilepsy are associated with aberrant neuronal connections, but the relationship between such pathological connectivity and the underlying physiological predisposition to seizures is unclear. We sought to characterize the cortical excitability profile of a developmental form of epilepsy known to have structural and functional connectivity abnormalities.

Methods: We employed transcranial magnetic stimulation (TMS) with simultaneous electroencephalographic (EEG) recording in 8 patients with epilepsy from periventricular nodular heterotopia and matched healthy controls.