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bioRxiv · 10.1101/2021.04.02.438254

Focal fMRI signal enhancement with implantable inductively coupled detectors

Chen, Y.·Wang, Q.·Choi, S.·Zeng, H.·Takahashi, K.·Qian, C.·Yu, X.
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Abstract

Despite extensive efforts to increase the signal-to-noise ratio (SNR) of fMRI images for brain-wide mapping, technical advances of focal brain signal enhancement are lacking, in particular, for animal brain imaging. Emerging studies have combined fMRI with fiber optic-based optogenetics to decipher circuit-specific neuromodulation from meso to macroscales. Acquiring fMRI signal with high spatiotemporal resolution is needed to bridge cross-scale functional dynamics, but SNR of targeted cortical regions is a limiting factor. We have developed a multi-modal fMRI imaging platform with an implanted inductive coil detector. This detector boosts the tSNR of MRI images, showing a 2-3 fold sensitivity gain over conventional coil configuration. In contrast to the cryoprobe or array coils with limited spaces for implanted brain interface, this setup offers a unique advantage to study brain circuit connectivity with optogenetic stimulation and can be further extended to other multi-modal fMRI mapping schemes.

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Chen, Y., Wang, Q., Choi, S., Zeng, H., Takahashi, K., Qian, C., Yu, X.. 2021-04-04. Focal fMRI signal enhancement with implantable inductively coupled detectors. https://doi.org/10.1101/2021.04.02.438254

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