A Practical Preprocessing Pipeline for Concurrent TMS-iEEG: Critical Steps and Methodological Considerations.

Transcranial magnetic stimulation combined with intracranial EEG (TMS-iEEG) has emerged as a powerful approach for probing the causal organization and dynamics of the human brain. Despite its promise, the presence of TMS-induced artifacts poses significant challenges for accurately characterizing and interpreting evoked neural responses. In this study, we present a practical preprocessing pipeline for single pulse TMS-iEEG data, incorporating key steps of re-referencing, filtering, artifact interpolation, and detrending.

Multimodal Evidence for Hippocampal Engagement and Modulation by Functional Connectivity-Guided Parietal TMS.

Hippocampal activity supports memory and many other brain functions. Transcranial magnetic stimulation (TMS) guided by hippocampal functional connectivity (FC) shows promise in improving memory, but direct neural evidence of its capacity to engage and modulate hippocampal activity is lacking. Here we combined TMS with intracranial electroencephalography (iEEG) in 8 neurosurgical patients and with functional magnetic resonance imaging (fMRI) in 79 neurologically healthy participants.

Genetics of Response to ECT, TMS, Ketamine and Esketamine.

Treatment-resistant mood disorders are often managed with intensive interventions that include electroconvulsive therapy (ECT), transcranial magnetic stimulation (TMS), ketamine, and esketamine, but the role of genetics in clinical response to those interventions is yet to be clearly determined. Here, we review the current literature on the genetics of response to these treatment modalities. To date, the limited number of studies done to investigate genetic predictors of treatment response have primarily focused on single variants in candidate genes, and none of these have been consistently reproducible.

Comparison of effectiveness of common targeting heuristics in repetitive transcranial magnetic stimulation treatment of depression.

Background: Repetitive transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC) is an effective non-pharmacological, non-invasive intervention for depression. However, the optimal strategy for localising the DLPFC treatment site on the patient's scalp is heavily disputed. Routine strategies were previously incrementally refined and compared in terms of anatomical accuracy, but little is known about their impact on clinical outcomes.

Reduced mind-wandering and fewer depressive symptoms associated with damage to the medial prefrontal cortex and default mode network.

Depressive disorders have been consistently associated with elevated levels of mind-wandering and self-focused negative rumination. Separate tracks of research have implicated brain structures within the default mode network (DMN) in both mind-wandering and depression. In this study, we hypothesized that diminished mind-wandering and fewer depressive symptoms would co-occur in individuals with damage to the DMN.

DLPFC Stimulation Suppresses High-Frequency Neural Activity in the Human sgACC.

Transcranial magnetic stimulation (TMS) to the dorsolateral prefrontal cortex (DLPFC) is hypothesized to relieve symptoms of depression by inhibiting activity in the subgenual anterior cingulate cortex (sgACC). However, we have a limited understanding of how TMS influences neural activity in the sgACC, owing to its deep location within the brain. To better understand the mechanism of antidepressant response to TMS, we recruited two neurosurgical patients with indwelling electrodes and delivered TMS pulses to the DLPFC while simultaneously recording local field potentials from the sgACC.

Towards accredited clinical training in brain stimulation: Proceedings from the brain stimulation subspecialty summits.

The rapid development and clinical use of brain stimulation has renewed debates about whether to define and accredit a pathway for clinical subspecialty training. To address this, the Brain Stimulation Subspecialty Summits (BraSSS) were convened in 2023 and 2024, featuring international leaders in brain stimulation across psychiatry, neurology, neurosurgery, psychology, and neuroscience. Both meetings included two days of lectures and debates focused on clinical content, emerging science, and educational standards.

Dorsolateral prefrontal cortex TMS evokes responses in the subgenual anterior cingulate cortex: Evidence from human intracranial EEG.

Transcranial magnetic stimulation combined with intracranial local field potential recordings in humans (TMS-iEEG) represents a new method for investigating electrophysiologic effects of TMS with spatiotemporal precision. We applied TMS-iEEG to the dorsolateral prefrontal cortex (dlPFC) in two subjects and demonstrate evoked activity in the subgenual anterior cingulate cortex (sgACC). This study provides direct electrophysiologic evidence that dlPFC TMS, as targeted for depression treatment, can modulate brain activity in the sgACC.

Consensus review and considerations on TMS to treat depression: A comprehensive update endorsed by the National Network of Depression Centers, the Clinical TMS Society, and the International Federation of Clinical Neurophysiology.

This article updates the prior 2018 consensus statement by the National Network of Depression Centers (NNDC) on the use of transcranial magnetic stimulation (TMS) in the treatment of depression, incorporating recent research and clinical developments. Publications on TMS and depression between September 2016 and April 2024 were identified using methods informed by PRISMA guidelines. The NNDC Neuromodulation Work Group met monthly between October 2022 and April 2024 to define important clinical topics and review pertinent literature.

The genetics of severe depression.

Genome-wide association studies (GWASs) of major depressive disorder (MDD) have recently achieved extremely large sample sizes and yielded substantial numbers of genome-wide significant loci. Because of the approach to ascertainment and assessment in many of these studies, some of these loci appear to be associated with dysphoria rather than with MDD, potentially decreasing the clinical relevance of the findings. An alternative approach to MDD GWAS is to focus on the most severe forms of MDD, with the hope that this will enrich for loci of larger effect, rendering their identification plausible, and providing potentially more clinically actionable findings.

TMS provokes target-dependent intracranial rhythms across human cortical and subcortical sites.

Background: Transcranial magnetic stimulation (TMS) is believed to alter ongoing neural activity and cause circuit-level changes in brain function. While the electrophysiological effects of TMS have been extensively studied with scalp electroencephalography (EEG), this approach generally evaluates low-frequency neural activity at the cortical surface. However, TMS can be safely used in patients with intracranial electrodes (iEEG), allowing for direct assessment of deeper and more localized oscillatory responses across the frequency spectrum.

Corrigendum: Early improvement predicts clinical outcomes similarly in 10 Hz rTMS and iTBS therapy for depression.

[This corrects the article DOI: 10.3389/fpsyt.2022.

Effects of transcranial magnetic stimulation on the human brain recorded with intracranial electrocorticography.

Transcranial magnetic stimulation (TMS) is increasingly used as a noninvasive technique for neuromodulation in research and clinical applications, yet its mechanisms are not well understood. Here, we present the neurophysiological effects of TMS using intracranial electrocorticography (iEEG) in neurosurgical patients. We first evaluated safety in a gel-based phantom.

Supra-second interval timing in bipolar disorder: examining the role of disorder sub-type, mood, and medication status.

Background: Widely reported by bipolar disorder (BD) patients, cognitive symptoms, including deficits in executive function, memory, attention, and timing are under-studied. Work suggests that individuals with BD show impairments in interval timing tasks, including supra-second, sub-second, and implicit motor timing compared to the neuronormative population. However, how time perception differs within individuals with BD based on disorder sub-type (BDI vs II), depressed mood, or antipsychotic medication-use has not been thoroughly investigated.

A randomized trial comparing beam F3 and 5.5 cm targeting in rTMS treatment of depression demonstrates similar effectiveness.

Background: The Beam F3 and 5.5 cm methods are the two most common targeting strategies for localizing the left dorsolateral prefrontal cortex (DLPFC) treatment site in repetitive transcranial magnetic stimulation (rTMS) protocols. This prospective, randomized, double-blind comparative effectiveness trial assesses the clinical outcomes for these two methods in a naturalistic sample of patients with major depressive disorder (MDD) undergoing clinical rTMS treatment.

TMS provokes target-dependent intracranial rhythms across human cortical and subcortical sites.

Transcranial magnetic stimulation (TMS) is increasingly deployed in the treatment of neuropsychiatric illness, under the presumption that stimulation of specific cortical targets can alter ongoing neural activity and cause circuit-level changes in brain function. While the electrophysiological effects of TMS have been extensively studied with scalp electroencephalography (EEG), this approach is most useful for evaluating low-frequency neural activity at the cortical surface. As such, little is known about how TMS perturbs rhythmic activity among deeper structures - such as the hippocampus and amygdala - and whether stimulation can alter higher-frequency oscillations.

Supra-second interval timing in bipolar disorder: examining the role of disorder sub-type, mood, and medication status.

: Widely reported by bipolar disorder (BD) patients, cognitive symptoms, including deficits in executive function, memory, attention, and timing are under-studied. Work suggests that individuals with BD show impairments in interval timing tasks, including supra-second, sub-second, and implicit motor timing compared to the neuronormative population. However, how time perception differs within individuals with BD based on BD sub-type (BDI vs II), mood, or antipsychotic medication-use has not been thoroughly investigated.

Individualized precision targeting of dorsal attention and default mode networks with rTMS in traumatic brain injury-associated depression.

At the group level, antidepressant efficacy of rTMS targets is inversely related to their normative connectivity with subgenual anterior cingulate cortex (sgACC). Individualized connectivity may yield better targets, particularly in patients with neuropsychiatric disorders who may have aberrant connectivity. However, sgACC connectivity shows poor test-retest reliability at the individual level.

Amygdala lesions are associated with improved mood after epilepsy surgery.

Neuroimaging studies in healthy and clinical populations strongly associate the amygdala with emotion, especially negative emotions. The consequences of surgical resection of the amygdala on mood are not well characterized. We tested the hypothesis that amygdala resection would result in mood improvement.

Neuroimaging Correlates of Post-Traumatic Stress Disorder in Traumatic Brain Injury: A Systematic Review of the Literature.

Neuroimaging is widely utilized in studying traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD). The risk for PTSD is greater after TBI than after non-TBI trauma, and PTSD is associated with worse outcomes after TBI. Studying the neuroimaging correlates of TBI-related PTSD may provide insights into the etiology of both conditions and help identify those TBI patients most at risk of developing persistent symptoms.