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

Concurrent recording of electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI) signals reveals cross-scale neurovascular dynamics crucial for explaining fundamental linkages between function and behaviors. However, MRI scanners generate artifacts for EEG detection. Despite existing denoising methods, cabled connections to EEG receivers are susceptible to environmental fluctuations inside MRI scanners, creating baseline drifts that complicate EEG signal retrieval from the noisy background. Here we show that a wireless integrated sensing detector for simultaneous EEG and MRI can encode fMRI and EEG signals on distinct sidebands of the detector's oscillation wave for detection by a standard MRI console over the entire duration of the fMRI sequence. Local field potential and fMRI maps are retrieved through low-pass and high-pass filtering of frequency-demodulated signals. From optogenetically stimulated somatosensory cortex in ChR2-transfected Sprague Dawley rats, positive correlation between evoked local field potential and fMRI signals validates strong neurovascular coupling, enabling cross-scale brain mapping with this two-in-one transducer.