The advances in electronics shielding and isolation of the field isolation containment system (FICS) have also been applied to allow 256-channel dEEG to be recorded in the MEG room, with no degradation of MEG quality. EGI's introduction of MR- and MEG-compatible dEEG systems with the FICS technology now provides a technology bridge between the spatial resolution of fMRI studies and the temporal resolution of MEG studies.

 

Early studies with 256-channel EEG and MEG from 4D neuroimaging showed the expected orthogonal orientations of the electrical and magnetic fields, as shown in the above image. Analysis of these data showed that 256-channel EEG provided localization of the somatosensory event-related potential that was equal to or better than that provided by whole-head MEG.

 

 

dEEG and MEG may be seen as competitive, but it is clear that when combined effectively they are synergistic. Simulation studies conducted by scientists at EGI and Los Alamos National Laboratory (LANL) have shown that joint dEEG-MEG recordings greatly improve localization precision. EEG and MEG fields are complementary, thus the improvement is more than additive, and can be described as truly synergistic. Shown here is the Brainstorm software for MEG and EEG developed by USC and LANL researchers.

 

For several years, EGI and LANL scientists have collaborated in simultaneous dEEG-MEG research. This research combined MEG-compatible dEEG prototypes with the advanced Superconducting Imaging Surface (SIS) MEG system at LANL. In the above image, the participant is placed in the SIS-MEG dewar (left); and the SIS SQUIDs (superconducting quantum interference devides) are shown arrayed in the dewar (right).

 

 

 

With the introduction of EGI's FICS MR-compatible dEEG system and HydroCel Geodesic Sensor Nets, EGI's dEEG is now compatible not only with the LANL SIS prototype, but with all commercial MEG systems as well. Shown here is a 128-channel HydroCel Net and the Elekta-Neuromag whole-head MEG system.