Elekta MAGNETOENCEPHALOGRAPHY (MEG)

University of Salzburg

Salzburg | Website

Large equipment

Short Description

Magnetoencephalography (MEG) is a neuroscientific technique that can be used to detect brain activity noninvasively with high temporal resolution. Analogously like the EEG, the underlying signal is directly attributable to neuronal activity.
Compared to the EEG, the MEG measures (extremely weak) changes of the magnetic field on the head surface. To achieve this, in addition to a complex magnetic shielding, the use of superconducting sensors (so-called SQUIDs) is necessary. In order to maintain the superconducting state, cooling by means of liquid helium is necessary.
The TRIUX system from Elekta, which is available at the MEG laboratory of the CCNS, has a total of 306 sensors (102 magnetometers and 204 gradiometers) that capture the signal from a total of 102 positions. If required, the deduction can be expanded by 128 EEG electrodes. The sampling rate of the device is up to max. 10kHz.
The laboratory is used by CDK mostly clinically (mainly for epilepsy diagnostics) and by researchers at the PLUS in the context of cognitive neuroscientific studies. For the latter area, a wide range of state-of-the-art stimulation devices (including visual, auditory, somatosensory) allow experimental diversity and flexibility. A special feature are two simultaneous controllable devices for transcranial electrical brain stimulation, the effect of which can be investigated "online" using MEG. The TRIUX system has been installed with a closed helium recovery system, which also saves time as well as eliminating the weekly "refills".

Contact Person

Prof. Dr. Nathan Weisz

Research Services

The Core Facility MEG supports all interested parties of the Salzburg neuroscientific community to carry out MEG studies at an international top level.
In addition to the provision of the laboratory, it includes the training of users, consultancy, etc.: a) at the design, b) at the implementation by means of the Psychophysics Toolbox, c) at the testing of the experientalscripts (including triggering and timing) and d) at the evaluation. Concerning the latter the core facility team regularly provides well-maintained and tested fieldtrip-based analysis pipelines.

Methods & Expertise for Research Infrastructure

A major advantage of this technique is that, unlike the EEG, the magnetic field penetrates the intervening layers (e.g., skull, scalp) without distortion. This usually results in a "cleaner" signal (better SNR) and easier handling of the modeling of basic generators. Thus, in addition to the time-high resolution, a spatial resolution (theoretically ~ 1 mm) satisfactory for many purposes is possible.
The Elekta TRIUX device allows carrying out investigations in which neuronal activity with high temporal resolution (currently up to a maximum of 10kHz) must be derived. This is highly relevant in many neurocognitive as well as clinical questions.
Apart from the consideration of "evoked" brain responses, an exact timing is also necessary to resolve oscillatory activity on different temporal scales. The use of modern inverse methods (normally in combination with a structural MRI) allows conclusions to be drawn on (probable) generators. Together with methods for the detection of the interaction between these generators, neural network dynamics can be investigated with spatial-temporally high resolution. This approach is becoming increasingly important in neurosciences.

Allocation to Core Facility

Cognitive Neuroscience

Prof. Dr. Nathan Weisz
Center for Cognitive Neuroscience
0043 662 8044 5120
nathan.weisz@sbg.ac.at
https://ccns.sbg.ac.at/
Please contact us via science.plus@sbg.ac.at, or contact the responsible person for this section, mentioned in the contact field
Psychology Department, University of Salzburg
Linguistic Department, University of Salzburg
Cell Biology Department, University of Salzburg
Molecular Biology Department, University of Salzburg
Christian-Doppler Klinik (CDK), Salzburg
MED-EL Elektromedizinische Geräte Gesellschaft m.b.H
Win2Con - Brain-state dependent perception: finding the windows to consciousness
2015-2017
Weisz, N.
ERC - European Research Council
Faith and oscillations recovered: On analyzing EEG/MEG signals during tACS
2017
Neuling, T., Ruhnau, P., Weisz, N., Herrmann, C.S. &, Demarchi, G.
NeuroImage, 147, 960-963
http://dx.doi.org/10.1016/j.neuroimage.2016.11.022

Interpretability of Multivariate Brain Maps in Linear Brain Decoding: Definition, and Heuristic Quantification in Multivariate Analysis of MEG Time-Locked Effects
2017
Kia, S. M., Vega-Pons, S., Weisz, N., & Passerini, A.
Frontiers in Neuroscience, 10(619)
http://dx.doi.org/10.1093/cercor/bhw138

The Tactile Window to Consciousness is Characterized by Frequency-specific Integration and Segregation of the Primary Somatosensory Cortex
2016
Frey, J., Ruhnau, P., Leske, S., Siegel, M., Braun, C., & Weisz, N.
Scientific Reports, 6: 20805
http://dx.doi.org/10.1038/srep20805

Limbic areas are functionally decoupled and visual cortex takes a more central role during fear conditioning in humans
2016
Lithari, C., Moratti, S., & Weisz, N.
Scientific Reports, 6: 29220
http://dx.doi.org/10.1038/srep29220

Large-scale network-level processes during entrainment
2016
Lithari C., Sanchez-Garcia, C., Ruhnau, P., & Weisz, N.
Brain Research, 1635, 143–152
http://dx.doi.org/10.1016/j.brainres.2016.01.043

Flicker-Driven Responses in Visual Cortex Change during Matched-Frequency Transcranial Alternating Current Stimulation
2016
Ruhnau, P., Keitel, C., Lithari, C., Weisz, N., & Neuling, T.
Frontiers in Human Neuroscience, 10: 184
http://dx.doi.org/10.3389/fnhum.2016.00184

Eyes wide shut: Transcranial alternating current stimulation drives alpha rhythm in a state dependent manner
2016
Ruhnau, P., Neuling, T., Fusca, M., Herrmann, C.S., Demarchi, G., & Weisz, N.
Scientific Reports, 6: 27138
http://dx.doi.org/10.1038/srep27138

Cross-modal distractors modulate oscillatory alpha power: the neural basis of impaired task performance
2016
Weise, A., Hartmann, T., Schröger, E., Weisz, N., & Ruhnau, P.
Psychophysiology, 53(11), 1651–1659
http://dx.doi.org/10.1111/psyp.12733

Alpha suppression and connectivity modulations in left temporal and parietal cortices index partial awareness of words
2016
Magazzini, L., Ruhnau, P., & Weisz, N.
NeuroImage, 133, 279-287
http://dx.doi.org/10.1016/j.neuroimage.2016.03.025

Spatially resolved time-frequency analysis of odour coding in the insect antennal lobe
2016
Paoli, M., Weisz, N., Antolini, R., & Haase, A.
European Journal of Neuroscience, 44(6), 2387-2395
http://dx.doi.org/10.1111/ejn.13344

Beta Band Modulations underlie Action Representations for Movement Planning
2016
Turella, L., Tucciarelli, R., Oosterhof, N.N., Weisz, N., Rumiati, R., & Lingnau, A.
Neuroimage, 136, 197–207
http://dx.doi.org/10.1016/j.neuroimage.2016.05.027

Temporal integration windows in neural processing and perception aligned to saccadic eye movements
2016
Wutz, A., Muschter, E., van Koningsbruggen, M.G., Weisz, N., & Melcher, D.
Current Biology, 26, 1659–1668
http://dx.doi.org/10.1016/j.cub.2016.04.070