Normal component of TMS-induced electric field is correlated with depressive symptom relief in treatment-resistant depression

Zhang, Bella B.B.; Stöhrmann, Peter; Godbersen, Godber Mathis; Unterholzner, Jakob; Kasper, S.; Kranz, Georg S.; Lanzenberger, Rupert

doi:10.1016/j.brs.2022.09.006

Cited by 17 publications

(10 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We compared the E-field normal component (E-norm) values for the A9/46v targeted region using three different methods: traditional nearest scalp site (NSS), the optimal coil placement provided by the SEM-based method, and the ADM method. The E-norm, which represents the component of the E-fields perpendicular to the cortical surface, is considered crucial for the clinical efficacy of TMS in depression treatment [34] . Our results demonstrate the superiority of the SEM-based over the NSS and ADM methods, as evidenced by significantly higher average E-norm values within the A9/46v targeted region in both the depression dataset and the CASIA II dataset of healthy subjects (Fig.…”

Section: Resultsmentioning

confidence: 99%

Stimulation Effects Mapping for Optimizing Coil Placement for Transcranial Magnetic Stimulation

Zhong,

Jin,

et al. 2024

Preprint

View full text Add to dashboard Cite

Transcranial magnetic stimulation (TMS) is a well-established non-invasive technique used to investigate brain function in health and disease. However, conventional methods of coil placement have limitations in accurately estimating the effects of TMS. Numerical modeling has shown promise in optimizing coil placement by providing a means to quantify the relationship between coil placement and region-specific electric field (E-field) effects. In this context, we propose the Stimulation Effects Mapping (SEM) framework to address this issue. The SEM framework aims to quantify It has been validated using diverse samples and neuroimaging data, allowing for standardized individual coil placements and optimal group-level positions. Through the analysis of a large dataset consisting of 5 million E-field modeling results from 212 participants, SEM consistently quantified the relationship between coil placement and region-specific E-field effects. In comparison to conventional methods and recent techniques, SEM-based optimal coil placement offers the same convenience while providing an improved understanding of depression treatment efficacy. By accurately quantifying the relationship between coil placement and E-field effects, SEM enables the identification of optimal coil positions that target specific cortical regions. This advancement in coil placement standardization overcomes limitations and promotes the precise modulation of brain activity based on E-field stimulation effects. The open-source nature of the SEM framework facilitates its adoption and encourages the precise modulation of brain activity through E-field stimulation. By leveraging the SEM framework, transcranial neuromodulation can be advanced, leading to improved outcomes in various applications.

show abstract

Section: Resultsmentioning

confidence: 99%

Stimulation Effects Mapping for Optimizing Coil Placement for Transcranial Magnetic Stimulation

Zhong,

Jin,

et al. 2024

Preprint

View full text Add to dashboard Cite

show abstract

“…To assess the effect of cTBS stimulation on the angular gyrus (Pizem et al, 2022; Zhang et al, 2022), we performed electric field simulations at 80 % of the individual motor threshold, averaging the estimated field strength within a 10mm sphere centered around the angular gyrus coordinate (MNI: −48, −67, 30). In order to examine whether the behavioral effects were dependent on the simulated electric field strength (Figure 2C), we next included electric field strength (strong vs. weak via median split) and repeated the previous linear mixed model predicting the number of details for linked events including a group factor reflecting stimulation strength (sham, low, high).…”

Section: Resultsmentioning

confidence: 99%

Causal role of the angular gyrus in insight-driven memory reconfiguration

Grob,

Heinbockel,

Milivojevic

et al. 2023

Preprint

View full text Add to dashboard Cite

Maintaining an accurate model of the world relies on our ability to update memory representations in light of new information. Previous research on the integration of new information into memory mainly focused on the hippocampus. Here, we hypothesized that the angular gyrus, known to be involved in episodic memory and imagination, plays a pivotal role in the insight-driven reconfiguration of memory representations. To test this hypothesis, participants received continuous theta burst stimulation (cTBS) inhibiting the left angular gyrus or sham stimulation before gaining insight into the relationship between previously separate life-like animated events in a narrative-insight task. During this task, participants also underwent EEG recording and their memory for linked and non-linked events was assessed shortly thereafter. Our results show that cTBS to the angular gyrus decreased memory for the linking events and reduced the memory advantage for linked relative to non-linked events. At the neural level, cTBS-induced angular gyrus inhibition reduced centro-temporal coupling with frontal regions and abolished insight-induced neural representational changes for events linked via imagination, indicating impaired memory reconfiguration. Further, the cTBS group showed representational changes for non-linked events that resembled the patterns observed in the sham group for the linked events, suggesting failed pruning of the narrative in memory. Together, our findings demonstrate a causal role of the left angular gyrus in insight-related memory reconfigurations.

show abstract

“…This improvement suggests potential enhancement in the accuracy of TMS language mapping and its applicability to more complex functional mapping. Notably, the association algorithm is utilized in the depression treatment to map the efficacy area of TMS, pending further confirmation regarding the selection of the electric field component ( Zhang et al, 2022 ). Therefore, the association algorithm also exhibits great potential in mapping the efficacy area in the TMS treatment for psychiatry.…”

Section: Discussionmentioning

confidence: 99%

Transcranial magnetic stimulation mapping of the motor cortex: comparison of five estimation algorithms

Chen,

Jiang,

Zhang

et al. 2023

Front. Neurosci.

View full text Add to dashboard Cite

BackgroundThere are currently five different kinds of transcranial magnetic stimulation (TMS) motor mapping algorithms available, from ordinary point-based algorithms to advanced field-based algorithms. However, there have been only a limited number of comparison studies conducted, and they have not yet examined all of the currently available algorithms. This deficiency impedes the judicious selection of algorithms for application in both clinical and basic neuroscience, and hinders the potential promotion of a potential superior algorithm. Considering the influence of algorithm complexity, further investigation is needed to examine the differences between fMRI peaks and TMS cortical hotspots that were identified previously.MethodsTwelve healthy participants underwent TMS motor mapping and a finger-tapping task during fMRI. The motor cortex TMS mapping results were estimated by five algorithms, and fMRI activation results were obtained. For each algorithm, the prediction error was defined as the distance between the measured scalp hotspot and optimized coil position, which was determined by the maximum electric field strength in the estimated motor cortex. Additionally, the study identified the minimum number of stimuli required for stable mapping. Finally, the location difference between the TMS mapping cortical hotspot and the fMRI activation peak was analyzed.ResultsThe projection yielded the lowest prediction error (5.27 ± 4.24 mm) among the point-based algorithms and the association algorithm yielded the lowest (6.66 ± 3.48 mm) among field-based estimation algorithms. The projection algorithm required fewer stimuli, possibly resulting from its suitability for the grid-based mapping data collection method. The TMS cortical hotspots from all algorithms consistently deviated from the fMRI activation peak (20.52 ± 8.46 mm for five algorithms).ConclusionThe association algorithm might be a superior choice for clinical applications and basic neuroscience research, due to its lower prediction error and higher estimation sensitivity in the deep cortical structure, especially for the sulcus. It also has potential applicability in various other TMS domains, including language area mapping and more. Otherwise, our results provide further evidence that TMS motor mapping intrinsically differs from fMRI motor mapping.

show abstract

Normal component of TMS-induced electric field is correlated with depressive symptom relief in treatment-resistant depression

Cited by 17 publications

References 11 publications

Stimulation Effects Mapping for Optimizing Coil Placement for Transcranial Magnetic Stimulation

Stimulation Effects Mapping for Optimizing Coil Placement for Transcranial Magnetic Stimulation

Causal role of the angular gyrus in insight-driven memory reconfiguration

Transcranial magnetic stimulation mapping of the motor cortex: comparison of five estimation algorithms

Contact Info

Product

Resources

About