WISDEM: a hybrid wireless integrated sensing detector for simultaneous EEG and MRI

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Simultaneous electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI) are vital for understanding brain dynamics.
• MRI scanners introduce artifacts that complicate EEG signal acquisition.
• Existing denoising methods struggle with baseline drifts caused by cabled EEG receivers in MRI environments.

Purpose of the Study:

• To develop a wireless integrated sensing detector for simultaneous EEG and MRI recording.
• To overcome the limitations of MRI-generated artifacts and baseline drifts in EEG signal retrieval.
• To enable robust cross-scale brain mapping by correlating neural and vascular signals.

Main Methods:

• A novel wireless detector encodes fMRI and EEG signals on distinct sidebands of its oscillation wave.
• Standard MRI console detects and processes the encoded signals throughout fMRI sequences.
• Frequency-demodulated signals are filtered (low-pass for LFP, high-pass for fMRI) for signal retrieval.
• Optogenetic stimulation of the somatosensory cortex in rats was used for validation.

Main Results:

• The wireless detector successfully encoded and retrieved both fMRI and EEG signals without significant interference.
• Local field potential (LFP) and fMRI maps were successfully generated from the processed signals.
• A strong positive correlation was observed between evoked LFP and fMRI signals in the stimulated somatosensory cortex.
• This validates the neurovascular coupling and the effectiveness of the two-in-one transducer.

Conclusions:

• The developed wireless integrated sensing detector facilitates simultaneous EEG and fMRI acquisition.
• This technology overcomes major challenges in concurrent EEG-fMRI recording, improving signal quality.
• It enables precise cross-scale brain mapping by demonstrating strong neurovascular coupling, advancing neuroscience research.