Evidence map›Paper›PMID 41720182›Full record

ArticleBrain stimulation

Layer-specific electric fields and effective conductivity in nonhuman primates during transcranial electrical stimulation.

Sangjun Lee, Arnaud Falchier, Alexander Opitz

Abstract read
In one paragraph

Article in Brain stimulation. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Sangjun LeeDepartment of Biomedical Engineering, University of Minnesota, MN, USA. Electronic address: lee03936@umn.edu.
Arnaud FalchierTranslational Neuroscience Lab Division, Center for Biomedical Imaging and Neuromodulation, The Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA; Department of Psychiatry NYU Grossman School of Medicine, New York City, NY, USA.
Alexander OpitzDepartment of Biomedical Engineering, University of Minnesota, MN, USA. Electronic address: aopitz@umn.edu.

Funding

Traveling Wave Transcranial Alternating Current Stimulation for the Control of Large-Scale Brain NetworksRF1MH124909 · NIMH · UNIVERSITY OF MINNESOTA · PI OPITZ, ALEXANDER · 2020 to 2020
$2.4M
NIMH NIH HHS RF1 MH124909
6 · The paper itself

Abstract

backgroundTranscranial electrical stimulation (tES) is widely used to modulate brain activity in a safe and non-invasive manner. tES generates weak electric fields in cortical tissues, which can modulate membrane potential and alter the timing of neural spikes. These electric fields interact with cortical circuits in a layer-specific manner; however, the distribution of tES-generated electric fields across cortical layers remains poorly understood. Because cortical layers differ in cytoarchitecture, electric fields are likely not uniform and may differ across layers. However, direct in vivo evidence of layer-specific TES electric fields is still lacking.

methodsWe conducted laminar recordings in the visual cortex of two nonhuman primates (NHPs) during low-frequency transcranial alternating current stimulation to capture layer-specific electric fields. To estimate layer-specific effective electrical conductivity, we compared these in vivo measurements with electric fields from finite element method (FEM) simulations. We first constructed a simplified sandwich model matching the dimensions of the laminar setup. Building on this, we then created a realistic multi-layer FEM head model of the NHP and optimized the effective conductivity of individual cortical layers by minimizing the error between measured and simulated electric fields.

resultsRepeated laminar recordings showed inhomogeneous electric fields across cortical layers, with a peak in electric field strength in layers 2/3 followed by a gradual decrease toward the white matter in both NHPs. Accordingly, optimization produced non-uniform conductivity values across layers, with the lowest conductivity in layers 2/3 and relatively higher values in white matter compared to commonly used reference values.

conclusionOur findings provide direct in vivo evidence for layer-specific electric fields and effective electrical conductivity at the mesoscale in the primate cortex, emphasizing the importance of considering laminar cortical organization. This work advances the fundamental understanding of how externally applied currents interact with the brain and provides a basis for more accurate computational models and clinically relevant neuromodulation strategies.

Indexed as

Models, NeurologicalTranscranial Direct Current StimulationVisual CortexAnimalsComputer SimulationElectric ConductivityFemaleFinite Element AnalysisSapajus apellaCortical layersFinite element modelLaminar recordingsLayer-specific effective electrical conductivityNonhuman primatesTranscranial electrical stimulation

Identifiers

PMID41720182
PMCPMC13027008

What OpenQuestion holds

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LicenceCC BY-NC-ND
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.